研究者データベース
| 真栄城 正寿(マエキ マサトシ) |
| 工学研究院 応用化学部門 分子機能化学分野 |
| 准教授 |
Last Updated :2024/05/09
基本情報
所属
職名
学位
ホームページURL
科研費研究者番号
- 40744248
ORCID ID
J-Global ID
研究キーワード
研究分野
担当教育組織
職歴
- 2022年04月 - 現在 高エネルギー加速器研究機構 物質構造科学研究所 客員准教授（兼任）
- 2021年04月 - 現在 北海道大学 大学院工学研究院 准教授
- 2019年10月 - 現在 JSTさきがけ研究員（兼任）
- 2019年04月 - 現在 ライラックファーマ株式会社 技術アドバイザー（兼任）
- 2018年07月 - 現在 理化学研究所 客員研究員（兼任）
- 2015年10月 - 2021年03月 北海道大学 大学院工学研究院応用化学部門 助教
- 2015年04月 - 2016年03月 国立研究開発法人 産業技術総合研究所 製造技術研究部門 外来研究員（兼任）
- 2014年04月 - 2015年09月 北海道大学 大学院工学研究院応用化学部門 日本学術振興会 特別研究員（PD）
- 2013年04月 - 2014年03月 九州大学 大学院総合理工学府物質理工学専攻 日本学術振興会特別研究員（DC2）
学歴
所属学協会
研究活動情報
論文
- Rina Naganawa, Hanjun Zhao, Yuta Takano, Masatoshi Maeki, Manabu Tokeshi, Hideyoshi Harashima, Yuma YamadaInternational Journal of Molecular Sciences 2024年04月12日
- Kunanon Chattrairat, Akira Yokoi, Min Zhang, Mikiko Iida, Kosuke Yoshida, Masami Kitagawa, Ayuka Niwa, Masatoshi Maeki, Takeshi Hasegawa, Takeshi Yokoyama, Yoshikazu Tanaka, Yusuke Miyazaki, Wataru Shinoda, Manabu Tokeshi, Kazuki Nagashima, Takeshi Yanagida, Hiroaki Kajiyama, Yoshinobu Baba, Takao YasuiDevice 100363 - 100363 2024年04月
- Masatoshi Maeki, Shuya Uno, Kaisei Sugiura, Yusuke Sato, Yoichiro Fujioka, Akihiko Ishida, Yusuke Ohba, Hideyoshi Harashima, Manabu TokeshiACS Applied Materials & Interfaces 2024年01月17日
- Masatoshi Maeki, Niko Kimura, Yuto Okada, Kazuki Shimizu, Kana Shibata, Yusuke Miyazaki, Akihiko Ishida, Kento Yonezawa, Nobutaka Shimizu, Wataru Shinoda, Manabu TokeshiNanoscale Advances 2024年
- Ryotaro Oyama, Harumichi Ishigame, Hiroki Tanaka, Naho Tateshita, Moeko Itazawa, Ryosuke Imai, Naomasa Nishiumi, Jun-ichi Kishikawa, Takayuki Kato, Jessica Anindita, Yoshifumi Nishikawa, Masatoshi Maeki, Manabu Tokeshi, Kota Tange, Yuta Nakai, Yu Sakurai, Takaharu Okada, Hidetaka AkitaACS Nano 2023年09月26日
- Akihiko Ishida, Takuma Nishimura, Kaito Koyama, Masatoshi Maeki, Hirofumi Tani, Manabu TokeshiJournal of Chromatography A 1706 464272 - 464272 2023年09月
- Keita Ito, Hiroto Furukawa, Hiroshi Inaba, Shino Ohshima, Yoshie Kametani, Masatoshi Maeki, Manabu Tokeshi, Xuhao Huang, Kazuya Kabayama, Yoshiyuki Manabe, Koichi Fukase, Kazunori MatsuuraJournal of the American Chemical Society 145 29 15838 - 15847 2023年06月21日
- Masatoshi Maeki, Niko Kimura, Yuto Okada, Kazuki Shimizu, Kana Shibata, Yusuke Miyazaki, Akihiko Ishida, Kento Yonezawa, Nobutaka Shimizu, Wataru Shinoda, Manabu Tokeshi2023年06月09日
- Mitsue Hibino, Masatoshi Maeki, Manabu Tokeshi, Yoichi Ishitsuka, Hideyoshi Harashima, Yuma YamadaScientific reports 13 1 6961 - 6961 2023年05月10日Mitochondria, a major source of reactive oxygen species (ROS), are intimately involved in the response to oxidative stress in the body. The production of excessive ROS affects the balance between oxidative responses and antioxidant defense mechanisms thus perturbing mitochondrial function eventually leading to tissue injury. Therefore, antioxidant therapies that target mitochondria can be used to treat such diseases and improve general health. This study reports on an attempt to establish a system for delivering an antioxidant molecule coenzyme Q10 (CoQ10) to mitochondria and the validation of its therapeutic efficacy in a model of acetaminophen (APAP) liver injury caused by oxidative stress in mitochondria. A CoQ10-MITO-Porter, a mitochondrial targeting lipid nanoparticle (LNP) containing encapsulated CoQ10, was prepared using a microfluidic device. It was essential to include polyethylene glycol (PEG) in the lipid composition of this LNP to ensure stability of the CoQ10, since it is relatively insoluble in water. Based on transmission electron microscope (TEM) observations and small angle X-ray scattering (SAXS) measurements, the CoQ10-MITO-Porter was estimated to be a 50 nm spherical particle without a regular layer structure. The use of the CoQ10-MITO-Porter improved liver function and reduced tissue injury, suggesting that it exerted a therapeutic effect on APAP liver injury.
- Masatoshi Maeki, Yuto Okada, Shuya Uno, Kaisei Sugiura, Yuichi Suzuki, Kento Okuda, Yusuke Sato, Masao Ando, Hiroyuki Yamazaki, Masaki Takeuchi, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Manabu TokeshiApplied Materials Today 2023年04月 [査読有り]
- Ahmed A. Shalaby, Chia Wen Tsao, Akihiko Ishida, Masatoshi Maeki, Manabu TokeshiSensors and Actuators B: Chemical 379 2023年03月15日 [査読有り]
Cancer is a leading cause of death worldwide. Early diagnosis of cancer is crucial for successful treatment which, in turn, will decrease mortality. The development of low-cost, accurate, and easy to operate point-of-need (PON) devices to be used for cancer diagnosis and treatment follow-up is a worldwide need, especially in developing countries. Paper-based analytical devices (PADs) are considered a key solution, as they provide a low-cost platform for developing PON biosensors for cancer biomarker detections. There are various types of 2D and 3D PADs according to the type of paper substrate (filter paper, chromatographic paper, nitrocellulose membranes, etc.), fabrication method (wax printing, screen printing, cutting, etc.), detection technique used (colorimetry, fluorescence, chemiluminescence, electrochemiluminescence, electrochemical, etc.), the assay principle and recognition element used (antibodies, aptamers, DNA, nanoparticles, enzymes, etc.). Controlling all these factors determines the performance, accuracy, and sensitivity of the developed devices. This review discusses all these factors in the different PADs used for detection of cancer biomarkers and summarizes the advantages and disadvantages of each one. - Shunsuke CHIDA, Kazuki TAKAHASHI, Mao FUKUYAMA, Motohiro KASUYA, Masatoshi MAEKI, Akihiko ISHIDA, Hirofumi TANI, Koji SHIGEMURA, Anatoly V. ZHERDEV, Sergei A. EREMIN, Akihide HIBARA, Manabu TOKESHIBUNSEKI KAGAKU 72 3 133 - 138 2023年03月05日 [査読有り][通常論文]
- Kaito Koyama, Takuma Nishimura, Akihiko Ishida, Mitsue Hibino, Masatoshi Maeki, Hirofumi Tani, Manabu Tokeshi分析化学 72 3 125 - 131 2023年03月
- Yuka Matsuura-Sawada, Shuya Uno, Masatoshi Maeki, Koichi Wada, Manabu TokeshiACS Applied Engineering Materials 2023年01月27日 [査読有り]
- Yu Nakashima, Atsushi Kawakami, Yasushi Ogasawara, Masatoshi Maeki, Manabu Tokeshi, Tohru Dairi, Hiroyuki MoritaNature Communications 2023年01月12日
- Yuka Matsuura-Sawada, Masatoshi Maeki, Shuya Uno, Koichi Wada, Manabu TokeshiBiomaterials Science 2023年 [査読有り]
The function of liposomal drugs and cosmetics is not only controlled by the lipid composition/formulation, but also by the liposome size and internal structure/properties (uni- and multi-lamellae) and membrane rigid/fluidic properties. Although the preparation of liposomes using microfluidic devices offers precise size control and easy scale-up in a continuous manufacturing system, their lamellarity and physicochemical property differences have not been investigated. We therefore prepared different paclitaxel (PTX)-loaded liposomes by changing two process parameters and investigated their physicochemical properties. The liposome size and drug loading were modified by changing the initial lipid concentration and flow rate ratio (FRR) of the aqueous and ethanol phases introduced into the microfluidic channels. Small-angle X-ray scattering and transmission electron microscopy revealed that the liposomes comprised a uni- or multi-lamellar structure that could be controlled by changing the FRR and initial lipid concentration. We also found that these structural differences affected the drug release profiles. Furthermore, the dissolution kinetics of the latter half of the drug release test could be modulated by the membrane fluidity of the liposomes. These differences in the drug release rates were consistent with the results of the in vitro cell viability assay, confirming that the multilamellar liposomes showed milder activity than the PTX solution by allowing the extended release of PTX. Thus, we concluded that the preparation of liposomes using microfluidic devices allows the liposome size, DL%, and drug release profiles to be adjusted as required. - Yi Bao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiACS Omega 7 37 33079 - 33086 2022年09月20日 [査読有り]
The translation of nanoparticles (NPs) from laboratory to clinical settings is limited, which is not ideal. One of the reasons for this is that we currently have limited ability to precisely regulate various physicochemical parameters of nanoparticles. This has made it difficult to rapidly perform targeted screening of drug preparation conditions. In this study, we attempted to broaden the range of preparation conditions for particle size-modulated poly(lactic-co-glycolic-acid) (PLGA) NP to enhance their applicability for drug delivery systems (DDS). This was done using a variety of organic solvents and a glass-based microfluidic device. Furthermore, we compared the PDMS-based microfluidic device to the glass-based microfluidic device in terms of the possibility of a wider range of preparation conditions, especially the effect of different solvents on the size of the PLGA NPs. PLGA NPs with different sizes (sub-200 nm) were successfully prepared, and three different types of taxanes were employed for encapsulation. The drug-loaded NPs showed size-dependent cytotoxicity in cellular assays, regardless of the taxane drug used. - Fumika Kubota, Satrialdi, Yuta Takano, Masatoshi Maeki, Manabu Tokeshi, Hideyoshi Harashima, Yuma YamadaJournal of biophotonics 16 3 e202200119 2022年09月01日 [査読有り]
Photodynamic therapy (PDT) is a cancer therapy that uses a photosensitizer (PS) in the presence of oxygen molecules. Since singlet oxygen is highly reactive, it is important to deliver it to the target site. Thus, an efficient drug delivery system (DDS) is essential for enhancing the efficacy of such a treatment and protecting against the side effects of PDT. Here, we report on attempts to increase the therapeutic effect of PDT by using a DDS, a lipid nanoparticle (LNP). We prepared a porphyrin analog, rTPA (PS) that was encapsulated in LNPs using a microfluidic device. The findings indicated that the internal structure of the prepared particles changed depending on the amount of rTPA in LNPs. The photoactivity and cell-killing effect of PS in LNPs also changed when the amount of the cargo increased. These results suggest that the internal structure of LNPs is important factors that affect drug efficacy. This article is protected by copyright. All rights reserved. - Yi Bao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiPLOS ONE 17 8 2022年08月 [査読有り]
The realization of poly (lactic-co-glycolic acid) nanoparticles (PLGA NPs) from laboratory to clinical applications remains slow, partly because of the lack of precise control of each condition in the preparation process and the rich selectivity of nanoparticles with diverse characteristics. Employing PLGA NPs to establish a large range of size-controlled drug delivery systems and achieve size-selective drug delivery targeting remains a challenge for therapeutic development for different diseases. In this study, we employed a microfluidic device to control the size of PLGA NPs. PLGA, poly (ethylene glycol)-methyl ether block poly (lactic-co-glycolide) (PEG-PLGA), and blend (PLGA + PEG-PLGA) NPs were engineered with defined sizes. Blend NPs exhibit the widest size range (40-114 nm) by simply changing the flow rate conditions without changing the precursor (polymer molecular weight, concentration, and chain segment composition). A model hydrophobic drug, paclitaxel (PTX), was encapsulated in the NPs, and the PTX-loaded NPs maintained a large range of controllable NP sizes. Furthermore, size-controlled NPs were used to investigate the effect of particle size of sub-200 nm NPs on tumor cell growth. The 52 nm NPs showed higher cell growth inhibition than 109 nm NPs. Our method allows the preparation of biodegradable NPs with a large size range without changing polymer precursors as well as the nondemanding fluid conditions. In addition, our model can be applied to elucidate the role of particle sizes of sub-200 nm particles in various biomedical applications, which may help develop suitable drugs for different diseases. - Yuka Matsuura-Sawada, Masatoshi Maeki, Takaaki Nishioka, Ayuka Niwa, Jun Yamauchi, Masashi Mizoguchi, Koichi Wada, Manabu TokeshiACS Applied Nano Materials 5 6 7867 - 7876 2022年06月24日 [査読有り]
The preparation of lipid-based nanoparticles (LNPs) using microfluidic devices offers significant advantages, such as precise size control and easy scale-up, in a continuous manufacturing system. However, improvements in this preparation method are needed to enhance LNP productivity to meet commercial, such as clinical and consumer, demands. Feeding a highly concentrated lipid solution into microfluidic devices to obtain a high concentration of LNPs is one of the ways to boost productivity. However, this has not been investigated in detail because a high concentration of lipids in ethanol makes it difficult to control the size and dispersity of LNPs. We previously developed iLiNP, a microfluidic device with simple baffle mixer structures, which can achieve rapid ethanol dilution. The applicability of iLiNP for producing LNPs by feeding a highly concentrated lipid solution has not been investigated. Herein, we demonstrate the preparation of monodispersed LNPs using a highly concentrated lipid solution. We compare the performance of iLiNP with those of three commercially available microfluidic devices. The area of the aqueous-ethanol interface and the dilution rate of ethanol significantly affects the size controllability and dispersity of LNPs at high lipid concentrations. Compared with other microfluidic devices, iLiNP could produce smaller and more concentrated (particles/mL) LNPs. We show that by controlling the LNP size using microfluidic devices, especially iLiNP, it is possible to feed highly concentrated lipid solutions. This feature of iLiNP could be a time- and cost-saving option for the mass production of LNPs for application in nanomedicine and cosmetics. - Kento Okuda, Yusuke Sato, Kazuki Iwakawa, Kosuke Sasaki, Nana Okabe, Masatoshi Maeki, Manabu Tokeshi, Hideyoshi HarashimaJournal of controlled release : official journal of the Controlled Release Society 348 648 - 659 2022年06月18日 [査読有り]
The use of lipid nanoparticles (LNPs) for nucleic acid delivery is now becoming a promising strategy with a number of clinical trials as vaccines or as novel therapies against a variety of genetic and infectious diseases. The use of microfluidics for the synthesis of the LNPs has attracted interest because of its considerable advantages over other conventional synthetic methods including scalability, reproducibility, and speed. However, despite the potential usefulness of large particles for nucleic acid delivery to dendritic cells (DCs) as a vaccine, the particle size of the LNPs prepared using microfluidics is typically limited to approximately from 30 to 100 nm. In this study, focusing on Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, the effect of some synthetic parameters, including total flow rate, flow rate ratio, buffer pH, lipid concentration, molar ratio of PEG-lipid as well as salt concentration, on particle size was systematically examined by means of the design of experiment approaches. The findings indicated that the simple addition of salt (e.g. NaCl) to a buffer containing nucleic acids contributed greatly to the synthesis of large LNPs over 200 nm and this effect was concentration-dependent with respect to the salt. The effect of salt on particle size was consistent with a Hofmeister series. The systemic injection of larger mRNA-loaded LNPs resulted in a higher transgene expression in mouse splenic DCs, a higher activation of various splenic immune cells, and had a superior effect as a therapeutic cancer vaccine in a syngeneic mouse model compared to the smaller-sized counterpart with constant lipid composition prepared with lower NaCl concentration. Collectively, size-regulation by the simple addition of salt is a promising strategy for developing potent LNPs. - Kazuki Takahashi, Shunsuke Chida, Thanawat Suwatthanarak, Mikiko Iida, Min Zhang, Mao Fukuyama, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Takao Yasui, Yoshinobu Baba, Akihide Hibara, Mina Okochi, Manabu TokeshiLab on a chip 22 16 2971 - 2977 2022年06月17日 [査読有り]
This paper is the first report of a non-competitive fluorescence polarization immunoassay (NC-FPIA) using a peptide as a tracer. The NC-FPIA can easily and quickly quantify the target after simply mixing them together. This feature is desirable for point-of-need applications such as clinical diagnostics, infectious disease screening, on-site analysis for food safety, etc. In this study, the NC-FPIA was applied to detect CD9, which is one of the exosome markers. We succeeded in detecting not only CD9 but also CD9 expressing exosomes derived from HeLa cells. This method can be applied to various targets if a tracer for the target can be prepared, and expectations are high for its future uses. - Masatoshi Maeki, Yuto Okada, Shuya Uno, Ayuka Niwa, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiJournal of visualized experiments : JoVE 2022 181 2022年03月22日 [査読有り]
The development of functional lipid nanoparticles (LNPs) is one of the major challenges in the field of drug delivery systems (DDS). Recently, LNP-based RNA delivery systems, namely, RNA-loaded LNPs have attracted attention for RNA therapy. In particular, mRNA-loaded LNP vaccines were approved to prevent COVID-19, thereby leading to the paradigm shift toward the development of next-generation nanomedicines. For the LNP-based nanomedicines, the LNP size is a significant factor in controlling the LNP biodistribution and LNP performance. Therefore, a precise LNP size control technique is indispensable for the LNP production process. Here, we report a protocol for size controlled LNP production using a microfluidic device, named iLiNP. siRNA loaded LNPs are also produced using the iLiNP device and evaluated by in vitro experiment. Representative results are shown for the LNP size, including siRNA-loaded LNPs, Z-potential, siRNA encapsulation efficiency, cytotoxicity, and target gene silencing activity. - Masatoshi Maeki, Shuya Uno, Ayuka Niwa, Yuto Okada, Manabu TokeshiJournal of controlled release : official journal of the Controlled Release Society 344 80 - 96 2022年02月17日 [査読有り]
In 2021, mRNA vaccines against COVID-19 were approved by the Food and Drug Administration. mRNA vaccines are important for preventing severe COVID-19 and returning to normal life. The development of RNA-delivery technology, including mRNA vaccines, has been investigated worldwide for ~30 years. Lipid nanoparticles (LNPs) are a breakthrough technology that stably delivers RNA to target organs, and RNA-loaded LNP-based nanomedicines have been studied for the development of vaccines and nanomedicines for RNA-, gene-, and cell-based therapies. Recently, microfluidic devices and technologies have attracted attention for the production of LNPs, particularly RNA-loaded LNPs. Microfluidics provides many advantages for RNA-loaded LNP production, including precise LNP size controllability, high reproducibility, high-throughput optimization of LNP formulation, and continuous LNP-production processes. In this review, we summarize microfluidic-based RNA-loaded LNP production and its applications in RNA-based therapy and genome editing. - Keine Nishiyama, Ryohei Mizukami, Shizuka Kuki, Akihiko Ishida, Junji Chida, Hiroshi Kido, Masatoshi Maeki, Hirofumi Tani, Manabu TokeshiBiosensors & bioelectronics 198 113832 - 113832 2022年02月15日 [査読有り]
This study aimed to develop an electrochemical system for measuring blood ATP and lactate levels in a single format. The ratio of lactate to ATP levels was previously reported to provide an alternative illness severity score. Although severity evaluation is crucial to treat patients with acute disease admitted to intensive care units, no sensors are currently available to simply and rapidly measure ATP and lactate levels using the same detection method. Therefore, we constructed an integrated sensing system for ATP and lactate using enzymatic reactions and two sets of electrodes integrated into a chip connected to a single potentiostat operated by a microcontroller. The enzymatic system involves adenylate kinase, pyruvate kinase, and pyruvate oxidase for ATP, and lactate oxidase for lactate, both of which produce hydrogen peroxide. Multiplex enzyme-based reactions were designed to minimize the corresponding operations significantly without enzyme immobilization onto the electrodes. The system was robust in the presence of potentially interfering blood components, such as ascorbate, pyruvate, ADP, urate, and potassium ions. The ATP and lactate levels in the blood were successfully measured using the new sensor with good recoveries. The analytical results of blood samples obtained using our sensor were in good agreement with those using conventional methods. Integrating electrode-based analysis and a microcontroller-based system saved further operations, enabling the straightforward measurement of ATP and lactate levels within 5 min. The proposed sensor may serve as a useful tool in the management of serious infectious diseases. - Onyinyechukwu Justina Oziri, Yubo Wang, Tomohisa Watanabe, Shuya Uno, Masatoshi Maeki, Manabu Tokeshi, Takuya Isono, Kenji Tajima, Toshifumi Satoh, Shin Ichiro Sato, Yutaka Miura, Takuya YamamotoNanoscale Advances 4 2 532 - 545 2022年01月21日Silver nanoparticles (AgNPs) are practically valuable in biological applications. However, no steady PEGylation has been established, which is essential for internal use in humans or animals. In this study, cyclic PEG (c-PEG) without any chemical inhomogeneity is physisorbed onto AgNPs to successfully PEGylate and drastically enhance the dispersion stability against physiological conditions, white light, and high temperature. In contrast, linear HO-PEG-OH and MeO-PEG-OMe do not confer stability to AgNPs, and HS-PEG-OMe, which is often used for gold nanoparticles, sulfidates the surface to considerably degrade the properties. TEM shows an essentially intact nanostructure of c-PEG-physisorbed AgNPs even after heating at 95 °C, while complete disturbance is observed for other AgNPs. Molecular weight- and concentration-dependent stabilization by c-PEG is investigated, and DLS and ζ-potential measurements prove the formation of a c-PEG layer on the surface of AgNPs. Furthermore, c-PEG-physisorbed AgNPs exhibit persistent antimicrobial activity and cytotoxicity.
- Onyinyechukwu Justina Oziri, Masatoshi Maeki, Manabu Tokeshi, Takuya Isono, Kenji Tajima, Toshifumi Satoh, Shin-Ichiro Sato, Takuya YamamotoLangmuir : the ACS journal of surfaces and colloids 38 17 5286 - 5295 2021年12月08日Unique physical and chemical properties arising from a polymer topology recently draw significant attention. In this study, cyclic poly(ethylene glycol) (c-PEG) was found to significantly interact with bovine serum albumin (BSA), suggested by nuclear magnetic resonance, dynamic light scattering, and fluorescence spectroscopy. On the other hand, linear HO-PEG-OH and MeO-PEG-OMe showed no affinity. Furthermore, a complex of gold nanoparticles and c-PEG (AuNPs/c-PEG) attracted BSA to form aggregates, and the red color of the AuNPs dispersion evidently disappeared, whereas ones with linear PEG or without PEG did not demonstrate such a phenomenon. The interactions among BSA, AuNPs, and PEG were investigated by changing the incubation time and concentration of the components by using UV-Vis and fluorescence spectroscopy.
- Ayano Nakamura, Mitsutoshi Aoyagi, Mao Fukuyama, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Koji Shigemura, Akihide Hibara, Manabu TokeshiACS Food Science & Technology 1 9 1623 - 1628 2021年10月15日With globalization, importing and exporting of agricultural products and foods have expanded, and food safety has become an important issue worldwide. Mycotoxin contamination of agricultural products and foods (processed foods) can occur anywhere, and it is desirable to develop a technology that can detect mycotoxin levels easily and quickly. By using a portable analyzer that can measure multiple samples simultaneously by combining a microfluidic device and a fluorescence polarization measurement system (a portable FP analyzer), we have successfully measured deoxynivalenol (DON), which is a common mycotoxin, easily and quickly by fluorescence polarized immunoassay (FPIA). The recovery rates of DON spiked in wheat, barley, cornmeal, flour, bread, pasta, thick wheat noodles (udon), and thin wheat noodles (somen) were between 86.3 and 113.2%, and the coefficient of variation was less than 8.5%. These FPIA results were in good agreement with results obtained by the official government-recognized method of liquid chromatography-mass spectrometry for DON analysis. The FP portable analyzer has great potential as an analytical tool that contributes to food safety.
- Keine Nishiyama, Kazuki Takahashi, Mao Fukuyama, Motohiro Kasuya, Ayuko Imai, Takumi Usukura, Nako Maishi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Kyoko Hida, Koji Shigemura, Akihide Hibara, Manabu TokeshiBiosensors and Bioelectronics 190 113414 - 113414 2021年10月15日Antibody detection methods for viral infections have received broad attention due to the COVID-19 pandemic. In addition, there remains an ever-increasing need to quantitatively evaluate the immune response to develop vaccines and treatments for COVID-19. Here, we report an analytical method for the rapid and quantitative detection of SARS-CoV-2 antibody in human serum by fluorescence polarization immunoassay (FPIA). A recombinant SARS-CoV-2 receptor binding domain (RBD) protein labeled with HiLyte Fluor 647 (F-RBD) was prepared and used for FPIA. When the anti-RBD antibody in human serum binds to F-RBD, the degree of polarization (P) increases by suppressing the rotational diffusion of F-RBD. The measurement procedure required only mixing a reagent containing F-RBD with serum sample and measuring the P value with a portable fluorescence polarization analyzer after 15 min incubation. We evaluated analytical performance of the developed FPIA system using 30 samples: 20 COVID-19 positive sera and 10 negative sera. The receiver operating characteristic curve drawn with the obtained results showed that this FPIA system had high accuracy for discriminating COVID-19 positive or negative serum (AUC = 0.965). The total measurement time was about 20 min, and the serum volume required for measurement was 0.25 μL. Therefore, we successfully developed the FPIA system that enables rapid and easy quantification of SARS-CoV-2 antibody. It is believed that our FPIA system will facilitate rapid on-site identification of infected persons and deepen understanding of the immune response to COVID-19.
- Takeshi Komatsu, Ryan Russel Gabatino, Harrienica Hofileña, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiJournal of Chemical Education 98 9 3050 - 3054 2021年09月14日The majority of chemical experiments conducted during educational programs are carried out in laboratories because they require instructors with special skills, in addition to large, expensive instruments. Recently, there has been an increasing demand for chemical experiments that can be carried out anywhere. Herein, we propose a novel type of paper-based analytical device (PAD) for enabling quantitative analysis without the requirement for a micropipette, since the PAD features a large sample loading zone and a waste zone, enabling accurate volume control of a liquid sample. We initially employed a micropipette to evaluate the PAD and demonstrate the quantitative analysis of ascorbic acid (AA) and pH using different loading volumes. Finally, we determined the AA concentrations and pH values of commercially available beverages using disposable plastic droppers, and the obtained results were in good agreement with those obtained through conventional methods. This PAD format can therefore be used as a novel educational tool for conducting certain chemical analyses in remote learning environments.
- Keine Nishiyama, Yohei Takeda, Kazuki Takahashi, Mao Fukuyama, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Koji Shigemura, Akihide Hibara, Haruko Ogawa, Manabu TokeshiANALYTICAL AND BIOANALYTICAL CHEMISTRY 413 18 4619 - 4623 2021年07月 [査読有り]
Nowadays, the diagnosis of viral infections is receiving broad attention. We have developed a non-competitive fluorescence polarization immunoassay (NC-FPIA), which is a separation-free immunoassay, for a virus detection. H5 subtype avian influenza virus (H5-AIV) was used as a model virus for the proof of concept. The fluorescein-labeled Fab fragment that binds to H5 hemagglutinin was used for NC-FPIA. The purified H5-AIV which has H5 hemagglutinin was mixed with the fluorescein-labeled Fab fragment. After that, the degree of fluorescence polarization was measured with a portable FPIA analyzer. H5-AIV was successfully detected with an incubation time of 15 min. In addition, the portable FPIA analyzer enables performance of on-site NC-FPIA with a sample volume of 20 mu L or less. This is the first research of detecting a virus particle by FPIA. This NC-FPIA can be applied to rapid on-site diagnosis of various viruses. - Hiroki Tanaka, Nae Takata, Yu Sakurai, Tokuyuki Yoshida, Takao Inoue, Shinya Tamagawa, Yuta Nakai, Kota Tange, Hiroki Yoshioka, Masatoshi Maeki, Manabu Tokeshi, Hidetaka AkitaPHARMACEUTICS 13 4 2021年04月 [査読有り]
The world-first success of lipid nanoparticle (LNP)-based siRNA therapeutics (ONPATTRO(R)) promises to accelerate developments in siRNA therapeutics/gene therapy using LNP-type drug delivery systems (DDS). In this study, we explore the optimal composition of an LNP containing a self-degradable material (ssPalmO-Phe) for the delivery of oligonucleotides. siRNA or antisense oligonucleotides (ASO) were encapsulated in LNP with different lipid compositions. The hepatic knockdown efficiency of the target genes and liver toxicity were evaluated. The optimal compositions for the siRNA were different from those for ASO, and different from those for mRNA that were reported in a previous study. Extracellular stability, endosomal escape and cellular uptake appear to be the key processes for the successful delivery of mRNA, siRNA and ASO, respectively. Moreover, the compositions of the LNPs likely contribute to their toxicity. The lipid composition of the LNP needs to be optimized depending on the type of nucleic acids under consideration if the applications of LNPs are to be further expanded. - Takeshi Komatsu, Ryoga Maeda, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiACS SENSORS 6 3 1094 - 1102 2021年03月The development of low-cost, user-friendly paper-based analytical devices (PADs) that can easily measure target chemicals is attracting attention. However, most PADs require manipulation of the sample using sophisticated micropipettes for quantitative analyses, which restricts their user-friendliness. In addition, immobilization of detection molecules to cellulose fibers is essential for achieving good measuring ability as it ensures the homogeneity of color development. Here, we have described a dip-type PAD that does not require pipette manipulation for sample introduction and immobilization of detection molecules to cellulose fibers and its application to ascorbic acid (AA) and pH assays. The PAD consisted of a dipping area and two channels, each with two detection zones. The developed PADs show color distribution in the two detection zones depending on the sample flow from the dipping area. In comparison with a PAD that has one detection zone at the end of the channel, our developed device achieved higher sensitivity (limit of detection (LOD), 0.22 mg/mL) and reproducibility (maximum coefficient of variation (CV), 2.4%) in AA detection. However, in pH detection, the reproducibility of the PAD with one detection zone at the end of the channel (maximum CV, 21%) was worse than that with two zones (maximum CV, 11%). Furthermore, a dipping time over 3 s did not affect color formation or calibration curves in AA detection: LODs at 3 and 30 s dipping time were 18 and 5.8 mu g/mL, respectively. The simultaneous determination of AA and pH in various beverages was performed with no significant difference compared to results of the conventional method.
- Keine Nishiyama, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Hideaki Hisamoto, Manabu TokeshiACS OMEGA 6 12 8340 - 8345 2021年03月 [査読有り]
Analytical methods with fluorescence detection are in widespread use for detecting low abundance analytes. Here, we report a simple method for fluorescence signal amplification utilizing a structure of an azide-unit pendant water-soluble photopolymer (AWP) in a microchannel. The AWP is a poly(vinyl alcohol)-based photocross-linkable polymer, which is often used in biosensors. We determined that the wall-like structure of the AWP (AWP-wall) constructed in a microchannel functioned as an amplifier of a fluorescence signal. When a solution of fluorescent molecules was introduced into the microchannel having the AWP-wall, the fluorescent molecules accumulated inside the AWP-wall by diffusion. Consequently, the fluorescence intensity inside the AWP-wall increased locally. Among the fluorescent molecules considered in this paper, 9H-(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl) (DDAO) showed the highest efficiency of fluorescence signal amplification. We prepared a calibration curve for DDAO using the fluorescence intensity inside the AWP-wall, and the sensitivity was 5-fold that for the microchannel without the AWP-wall. This method realizes the improved sensitivity of fluorescence detection easily because the fluorescence signal was amplified only by injecting the solution into the microchannel having the AWP-wall. Furthermore, since this method is not limited to only the use of microchannel, we expect it to be applicable in various fields. - Takeshi Komatsu, Yuki Sato, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiANALYTICA CHIMICA ACTA 1144 85 - 95 2021年02月 [査読有り]
Competitive immunoassays comprise the standard means of detecting small molecules. However, conventional methods using microwells are difficult to apply during point-of-care tests (POCT) because they require complicated handling and are time consuming. Although paper-based analytical devices (PAD) have received considerable focus because of their rapid and straightforward operation, only a few devices have been proposed for competitive immunoassays. Herein, we describe a novel universal PAD format with a 3-dimensional configuration for competitive immunoassays that rapidly and sensitively detects small molecules. The proposed device comprised a layered structure with uniform color formation and high capture efficiency between antigen and antibody that results in rapid and reproducible results. The device rapidly (90 s) assayed biotin as a model target, with a limit of detection (LOD) of 5.08 ng mL(-1), and detected progesterone with an LOD of 84 pg mL(-1) within 5 min. Moreover, sample volumes and reagent consumption rates were minimized. Thus, our device could be applied to competitive immunoassays of various small molecules in POCT. (C) 2020 Elsevier B.V. All rights reserved. - Yuichi Suzuki, Haruno Onuma, Risa Sato, Yusuke Sato, Akari Hashiba, Masatoshi Maeki, Manabu Tokeshi, Mohammad Enamul Hoque Kayesh, Michinori Kohara, Kyoko Tsukiyama-Kohara, Hideyoshi HarashimaJOURNAL OF CONTROLLED RELEASE 330 61 - 71 2021年02月 [査読有り]
The clustered regularly interspaced short palindromic repeats (CRISPR)-associated (Cas) system has considerable therapeutic potential for use in treating a wide range of intractable genetic and infectious diseases including hepatitis B virus (HBV) infections. While non-viral delivery technologies for the CRISPR/Cas system are expected to have clinical applications, difficulties associated with the clinically relevant synthesis of formulations and the poor efficiency of delivery severely hinder therapeutic genome editing. We report herein on the production of a lipid nanoparticle (LNP)-based CRISPR/Cas ribonucleoprotein (RNP) delivery nanoplatform synthesized using a clinically relevant mixer-equipped microfluidic device. DNA cleavage activity and the aggregation of Cas enzymes was completely avoided under the optimized synthetic conditions. The optimized formulation, which was identified through 2 steps of design of experiments, exhibited excellent gene disruption (up to 97%) and base substitution (up to 23%) without any apparent cytotoxicity. The addition of negative charges to the RNPs by complexing single-stranded oligonucleotide (ssON) significantly enhanced the delivery of both Cas9 and Cpf1 RNPs. The optimized formulation significantly suppressed both HBV DNA and covalently closed circular DNA (cccDNA) in HBV-infected human liver cells compared to adeno-associated virus type 2 (AAV2). These findings represent a significant contribution to the development of CRISPR/Cas RNP delivery technology and its practical applications in genome editing therapy. - Niko Kimura, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiACS APPLIED BIO MATERIALS 4 2 1783 - 1793 2021年02月 [査読有り]
Size-controlled lipid nanoparticle (LNP)-based DNA/RNA delivery is a leading technology for gene therapies. For DNA/RNA delivery, typically, a cationic lipid is used to encapsulate DNA/RNA into LNPs. However, the use of the cationic lipid leads to cytotoxicity. In contrast, noncationic NPs, such as exosomes, are ideal nanocarriers for DNA/RNA delivery. However, the development of a simple one-step method for the production of size-controlled noncationic NPs encapsulating DNA/RNA is still challenging because of the lack of electrostatic interactions between the cationic lipid and negatively charged DNA/RNA. Herein, we report a microfluidic-based one-step method for the production of size-controlled noncationic NPs encapsulating small interfering RNA (siRNA). Our microfluidic device, named iLiNP, enables the efficient encapsulation of siRNA, as well as control over the NP size, by varying the flow conditions. We applied this method to produce size-controlled exosome-like NPs. The siRNA-loaded exosome-like NPs did not show in vitro cytotoxicity at a high siRNA dosage. In addition, we investigated the effect of the size of the exosome-like NPs on the target gene silencing and found that the 40-50 nm-sized NPs suppressed target protein expression at a dose of 20 nM siRNA. The iLiNP-based one-step production method for size-controlled noncationic-NP-encapsulated RNA is a promising method for the production of artificial exosomes and functionally modified exosomes for gene and cell therapies. - Kunanon Chattrairat, Takao Yasui, Masatoshi Maeki, Manabu Tokeshi, Yoshinobu BabaMicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences 1179 - 1180 2021年Recently, genetic information from miRNAs has provided early diagnosis as biological biomarkers. However, separating free-floating miRNAs from exosomal miRNAs is still challenging due to its nano-size and possible interference in downstream analysis. In this work, we developed an integrated microfluidic ZnO nanowires device with a thermoelectric controller for separating free-floating miRNA (ff-miRNAs) from miRNA-encapsulated artificial extracellular vesicles nanoparticles (NPs).
- Niko Kimura, Masatoshi Maeki, Kosuke Sasaki, Yusuke Sato, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Manabu TokeshiRSC ADVANCES 11 3 1430 - 1439 2021年01月 [査読有り]
Sub 100 nm-sized lipid nanoparticles (LNPs) have been widely used in drug delivery systems (DDSs). The size of the LNPs is an important parameter for the DDS performance, such as biodistribution and gene silencing using siRNAs. However, the LNPs prepared by the conventional preparation method show a wide size distribution. To improve the LNP size distribution, we developed a microfluidic device, named the iLiNP (TM) device, in a previous study. This device could produce LNPs in the size range of 20 to 150 nm, but the size distribution of the large-sized LNPs needs to be further improved. From the viewpoint of the LNP formation process, a homogeneous and slow rate dilution of ethanol plays an important role in improving the large-size LNP size distribution. In this study, we developed a three-dimensional, symmetrically assembled microfluidic device named the 3D-iLiNP device with the aim of precise size control of large-sized LNPs. We designed the 3D-iLiNP device using a computational fluid dynamics simulation and demonstrated that the 3D-iLiNP device can improve the LNP size distribution. The gene silencing activity of four kinds of siRNA-loaded LNPs was investigated via in vitro and in vivo experiments to elucidate the effect of the LNP size distribution. The results revealed that the LNPs with a size between 90 and 120 nm showed higher gene silencing activity than those with other sizes. The 3D-iLiNP device is expected to improve DDS performance by precisely controlling the size of LNPs. - Keine Nishiyama, Mao Fukuyama, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu TokeshiSENSORS AND ACTUATORS B-CHEMICAL 326 128982 - 128982 2021年01月 [査読有り]
A non-competitive fluorescence polarization immunoassay (FPIA) using a Fab fragment was developed for large molecule quantification. Most conventional FPIAs are homogeneous and competitive immunoassays. With competitive FPIAs, it has been difficult to obtain sufficient detection sensitivity when targeting large molecules like proteins. To overcome this fundamental drawback, we report a non-competitive FPIA using a fluorescence-labeled Fab fragment. C-reactive protein (CRP) was used as model substance for validation of the Fab-based non-competitive FPIA. Quantitative analysis of CRP in phosphate buffered saline (PBS) was successfully achieved and the limit of detection (LOD) of CRP in PBS was 207 ng/mL. Moreover, using far-red emitting fluorescent dye (HiLyte Fluor (TM) 647) as a fluorescent labeling substance of Fab fragment, we measured CRP in human serum without pretreatment of a sample in 10 min around the cut-off value of CRP (10 mu g/mL). The LOD of CRP in human serum was 1.58 mu g/mL. In our proposed method, the reaction was completed in a simple one-step mixing with only one type of fluorescence-labeled Fab fragment reagent, and no washing operation was required. Therefore, rapid protein quantification was achieved with a greatly simplified procedure. - Yubo Wang, Jose Enrico Q. Quinsaat, Tomoko Ono, Masatoshi Maeki, Manabu Tokeshi, Takuya Isono, Kenji Tajima, Toshifumi Satoh, Shin-ichiro Sato, Yutaka Miura, Takuya YamamotoNATURE COMMUNICATIONS 11 1 6089 - 6089 2020年11月 [査読有り]
Nano-sized metal particles are attracting much interest in industrial and biomedical applications due to the recent progress and development of nanotechnology, and the surface-modifications by appropriate polymers are key techniques to stably express their characteristics. Herein, we applied cyclic poly(ethylene glycol) (c-PEG), having no chemical inhomogeneity, to provide a polymer topology-dependent stabilization for the surface-modification of gold nanoparticles (AuNPs) through physisorption. By simply mixing c-PEG, but not linear counterparts, enables AuNPs to maintain dispersibility through freezing, lyophilization, or heating. Surprisingly, c-PEG endowed AuNPs with even better dispersion stability than thiolated PEG (HS-PEG-OMe). The stronger affinity of c-PEG was confirmed by DLS,.-potential, and FT-IR. Furthermore, the c-PEG system exhibited prolonged blood circulation and enhanced tumor accumulation in mice. Our data suggests that c-PEG induces physisorption on AuNPs, supplying sufficient stability toward bio-medical applications, and would be an alternative approach to the gold-sulfur chemisorption. - Akari Hashiba, Manaya Toyooka, Yusuke Sato, Masatoshi Maeki, Manabu Tokeshi, Hideyoshi HarashimaJOURNAL OF CONTROLLED RELEASE 327 467 - 476 2020年11月 [査読有り][通常論文]
Although great advances have been made in the delivery of short RNAs by lipid nanoparticles (LNPs), the optimal formulation composition and physicochemical properties of LNPs for long RNA (including mRNA) remain unclear. In the present study, we optimized the lipid composition of liver-targeted mRNA-loaded LNPs that were prepared with pH-sensitive cationic lipids that had been previously designed for siRNA delivery through a two stepped design of experiment (DoE). Multiple responses including physicochemical properties, gene expression, and liver-specificity were analyzed in order, not only to understand the role of each formulation parameter, but also to examine parameters that would be difficult to predict. We found that particle size and the PEG-to-phospholipid (PEG/PL) ratio were additional key factors for liver-specific gene expression in addition to the other formulation factors. The optimized formulation showed a better gene expression compared to other lipid formulations from industry leaders. These findings suggest that a "DoE with multiple responses" approach can be used to predict significant parameters and permit optimized formulations to be prepared more efficiently. - Masatoshi Maeki, Sho Ito, Reo Takeda, Go Ueno, Akihiko Ishida, Hirofumi Tani, Masaki Yamamoto, Manabu TokeshiCHEMICAL SCIENCE 11 34 9072 - 9087 2020年09月 [査読有り][通常論文]
Room-temperature (RT) protein crystallography provides significant information to elucidate protein function under physiological conditions. In particular, contrary to typical binding assays, X-ray crystal structure analysis of a protein-ligand complex can determine the three-dimensional (3D) configuration of its binding site. This allows the development of effective drugs by structure-based and fragmentbased (FBDD) drug design. However, RT crystallography and RT crystallography-based protein-ligand complex analyses require the preparation and measurement of numerous crystals to avoid the X-ray radiation damage. Thus, for the application of RT crystallography to protein-ligand complex analysis, the simultaneous preparation of protein-ligand complex crystals and sequential X-ray diffraction measurement remain challenging. Here, we report an RT crystallography technique using a microfluidic protein crystal array device for protein-ligand complex structure analysis. We demonstrate the microfluidic sorting of protein crystals into microwells without any complicated procedures and apparatus, whereby the sorted protein crystals are fixed into microwells and sequentially measured to collect X-ray diffraction data. This is followed by automatic data processing to calculate the 3D protein structure. The microfluidic device allows the high-throughput preparation of the protein-ligand complex solely by the replacement of the microchannel content with the required ligand solution. We determined eight trypsin-ligand complex structures for the proof of concept experiment and found differences in the ligand coordination of the corresponding RT and conventional cryogenic structures. This methodology can be applied to easily obtain more natural structures. Moreover, drug development by FBDD could be more effective using the proposed methodology. - Taiga Ajiri, Takao Yasui, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Junji Nishii, Yoshinobu Baba, Manabu TokeshiACS APPLIED NANO MATERIALS 3 9 8810 - 8816 2020年09月 [査読有り][通常論文]
Recent studies on nanopillar arrays, one type of nanofluidic device, have demonstrated various tools for bioanalysis. When carrying out nanopillar array-based separation, it is indispensable to observe biomolecules, such as DNA, proteins, and extracellular vesicles, that have fluorescence labeling; however, fluorescence labeling influences the biomolecular characteristics. Here, we have proposed label-free monitoring of biomolecule separation by using diffracted light derived from the nanopillar array that was fabricated inside a microchannel by combining laser interference lithography with general photolithography techniques. Using an electrophoresis approach, we demonstrated that our diffraction-based label-free method possessed high sensor initialization ability, and the nanopillar array device successfully monitored DNA separation without labeling bias. Results obtained using our label-free monitoring of DNA separation confirmed, for the first time, that the molecular dynamics of DNA molecules in the nanopillar array were changed in the presence or absence of fluorescent labeling. The presented concept will provide a useful tool for nonbiased monitoring of label-free biomolecule analysis in nanofluidic channels. - Masatoshi Maeki, Shohei Yamazaki, Reo Takeda, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiACS OMEGA 5 28 17199 - 17206 2020年07月 [査読有り][通常論文]
Preparation of high-quality protein crystals is a major challenge in protein crystallography. Natural convection is considered to be an uncontrollable factor of the crystallization process at the ground level as it disturbs the concentration gradient around the growing crystal, resulting in lower-quality crystals. A microfluidic environment expects an imitated microgravity environment because of the small Gr number. However, the mechanism of protein crystal growth in the microfluidic device was not elucidated due to limitations in measuring the crystal growth process within the device. Here, we demonstrate the real-time measurement of protein crystal growth rates within the microfluidic devices by laser confocal microscopy with differential interference contrast microscopy (LCM-DIM) at the nanometer scale. We confirmed the normal growth rates in the 20 and 30 mu m-deep microfluidic device to be 42.2 and 536 nm/min, respectively. In addition, the growth rate of crystals in the 20 mu m-deep microfluidic device was almost the same as that reported in microgravity conditions. This phenomenon may enable the development of more accessible alternatives to the microgravity environment of the International Space Station. - Niko Kimura, Masatoshi Maeki, Yusuke Sato, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Manabu TokeshiACS APPLIED MATERIALS & INTERFACES 12 30 34011 - 34020 2020年07月 [査読有り][通常論文]
Microfluidic methodologies for preparation of lipid nanoparticles (LNPs) based on an organic solvent injection method enable precise size control of the LNPs. After preparation of LNPs, the organic solvent injection method needs some post-treatments, such as overnight dialysis or direct dilution with a buffer solution. LNP production using the microfluidic-based organic solvent injection method is dominated by kinetics rather than thermodynamics. Kinetics of ethanol removal from the inner and outer membranes of LNPs could induce a structural change in the membrane that could lead to fusion of LNPs. However, the effects of microfluidic post-treatment on the final size of LNPs have not been sufficiently understood. Herein, we investigated the effect of the post-treatment processes on the final product size of LNPs in detail. A simple baffle device and a model lipid system composed of a neutral phospholipid (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, POPC) and cholesterol were used to produce the LNPs. We demonstrated that flow conditions of the post-treatment diluting the remaining ethanol in the LNP suspension affected the final product size of LNPs. Based on the findings, we developed an integrated baffle device composed of an LNP production region and a post-treatment region for a microfluidic-based LNP production system; this integrated baffle device prevented the undesirable aggregation or fusion of POPC LNPs even for the high-lipid-concentration condition. Finally, we applied our concept to small interfering RNA (siRNA) delivery and confirmed that no significant effects due to the continuous process occurred on the siRNA encapsulation efficiency, biological distribution, and knockdown activity. The microfluidic post-treatment method is expected to contribute to the production of LNPs for practical applications and the development of novel LNP-based nanomedicines. - Keine Nishiyama, Yohei Takeda, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Koji Shigemura, Akihide Hibara, Yutaka Yonezawa, Kunitoshi Imai, Haruko Ogawa, Manabu TokeshiSENSORS AND ACTUATORS B-CHEMICAL 316 128160 - 128160 2020年07月 [査読有り][通常論文]
A rapid, facile and selective detection of anti-H5 subtype avian influenza virus (AIV) antibody in serum by fluorescence polarization immunoassay (FPIA) was achieved. A fragment of recombinant H5 subtype AIV hemagglutinin was produced and labeled with fluorescein to use it as a labeled antigen in FPIA. This labeled antigen was mixed with anti-AIV sera (H1-H16 subtypes) and FP of the mixture was measured using a portable FP analyzer on a microdevice. It was found that FP increased in proportion to the concentration of anti-H5 AIV antibody (serum) and was significantly higher than FP obtained with the other sera. The selective detection of anti-H5 subtype AIV antibody was confirmed. The required volume of original sample was 2 mu L and analysis time was within 20 min. This detection system realizes an efficient on-site diagnosis and surveillance of AIV. - Takeshi Komatsu, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiACS SENSORS 5 5 1287 - 1294 2020年05月 [査読有り][通常論文]
Lithium carbonate is an effective medicine for the treatment of the bipolar disorder, but the concentration of lithium in the patient's blood must be frequently monitored because of its toxicity. To date, no colorimetric methods of lithium ion detection in whole blood without pretreatment have been reported. Here, we report a colorimetric paper-based device that allows point-of-care testing in one step. This device is composed of two paper-based elements linked to each other: a blood cell separation unit and a colorimetric detection unit. After a portion of whole blood has been placed on the end of the separation unit, plasma in the sample is automatically transported to the detection unit, which displays a diagnostic color. The key feature of this device is its simple, user-friendly operation. The limit of detection is 0.054 mM and the coefficient of variance is below 6.1%, which are comparable to those of conventional instruments using the same colorimetric reaction. Furthermore, we achieved high recovery (>90%) and reproducibility (<9.8%) with spiked human blood samples. Thus, the presented device provides an alternative method for the regular monitoring of lithium concentrations in the treatment of bipolar disorder by augmenting the coefficient of variation (maximum value, 6.1%). - Takashi Nakamura, Minori Kawai, Yusuke Sato, Masatoshi Maeki, Manabu Tokeshi, Hideyoshi HarashimaMolecular Pharmaceutics 17 3 944 - 953 2020年03月02日
- Yusuke Sato, Nana Okabe, Yusuke Note, Kazuki Hashiba, Masatoshi Maeki, Manabu Tokeshi, Hideyoshi HarashimaACTA BIOMATERIALIA 102 341 - 350 2020年01月 [査読有り][通常論文]
Despite the fact that small-sized lipid nanoparticles (LNPs) are important for improved tissue penetration and efficient drug delivery, their poor stability and intracellular trafficking significantly hinders their use as potent small-sized LNPs. It has been reported that both the diffusion of lipid components from LNPs and the adsorption of proteins on the surface of LNPs are responsible for their decreased potency. To overcome this issue, we focused on the chemical structure of hydrophobic scaffolds of pH-sensitive cationic lipids with various lengths and shapes. LNPs composed of a pH-sensitive cationic lipid with long, linear scaffolds induced gene silencing in a dose-dependent manner, while LNPs with a classical scaffold length (C18) failed. Replacing the helper lipid from cholesterol to egg sphingomyelin (ESM) resulted in the formation of smaller LNPs with a diameter of similar to 22 nm and enhanced gene silencing activity. Most of the ESMs were located in the outer layer and functioned to stabilize the LNPs. Long, linear scaffolds contributed to immiscibility with phosphocholine-containing lipids including ESM. This contribution was dependent on the scaffold length of pH-sensitive cationic lipids. Although phosphocholine-containing lipids usually inhibit membrane fusion-mediated endosomal escape, long, linear scaffolds contributed to avoiding the inhibitory effect and to enhance the potency of the LNPs. These findings provide useful information needed for the rational design of pH-sensitive cationic lipid structures and the selection of appropriate helper lipids and will facilitate the development of highly potent small-sized LNPs.Statement of significanceDespite the fact that small-sized lipid nanoparticles (LNPs) are important for improved tissue penetration and efficient drug delivery, the size reduction-associated decrease in the stability and intracellular trafficking significantly hinders the development of potent small-sized LNPs. Our limited understanding of the mechanism underlying the reduced potency has also hindered the development of more potent small-sized LNPs. The findings of the present study indicate that long and linear hydrophobic scaffolds of pH-sensitive cationic lipids could overcome the loss of efficiency for nucleic acid delivery. In addition, the long hydrophobic scaffolds led to immiscibility with neutral phospholipids, resulting in efficient endosomal escape. These findings provide useful information needed for the rational design of pH-sensitive cationic lipid structures and will facilitate the development of highly potent small-sized LNPs. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. - Donny Nugraha Mazaafrianto, Akihiko Ishida, Masatoshi Maeki, Hirofumi Tani, Manabu TokeshiANALYTICAL SCIENCES 35 11 1221 - 1226 2019年11月 [査読有り][通常論文]
In this study, we developed an electrochemical sensor for ochratoxin A (OTA) by using an aptamer having a dithiol-based anchor, which exhibited higher stability on a gold electrode than a monothiol-based aptamer because of its two anchors. The sensor was also based on a signal-on scheme that produces a signal current resulting from structure-switching of the aptamer upon interaction with OTA. For simple fabrication of this sensor, the non-covalent interaction of methylene blue with the aptamer was also employed as an electrochemical indicator. In this study, the performance of the sensor, including the dissociation constant of the aptamer-OTA complex, was characterized. The proposed sensor exhibited high reproducibility and enough sensitivity to detect the minimum amount of OTA required for the analysis of real food samples with a limit of detection of 113 pM. - Kenia Chavez Ramos, Keine Nishiyama, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Toshihiro Kasama, Yoshinobu Baba, Manabu TokeshiACS OMEGA 4 15 16683 - 16688 2019年10月 [査読有り][通常論文]
Avian influenza virus (AIV) infection, caused by influenza virus type A, is an infectious, acute respiratory disease of birds related to influenza outbreaks worldwide. The highly pathogenic AIV subtype H5N1 has crossed species barriers to infect mammals, including humans, with fatal outcomes and has received attention as a potential pandemic threat. A rapid and timely detection in poultry is vitally important to prevent the virus spread. Despite their great sensitivity, conventional detection methods such as real-time reverse transcription-polymerase chain reaction and the agar gel precipitation test are time-consuming and labor-intensive and require special training. In this work, an immunowall device was evaluated as an easier and faster way for detecting AIV H5-hemagglutinin (AIV H5-HA). For detection, fluorescence-labeled or enzyme-labeled antibody was employed as a labeling antibody in a sandwich immunoassay. Both were shown in this paper to be easier and faster assays for detection compared with the conventional enzyme-linked immunosorbent assay (ELISA) kit. In addition, high selectivity was achieved for AIV H5-HA detection after the evaluation of other different HA virus subtypes. The limit of detection was 0.23 ng/mL for the enzyme-labeled antibody. This value was equivalent to that of the conventional ELISA kit but 8 times faster (31 min compared to 260 min). The detection range was 0.23-100 ng/mL. The immunowall device with the enzyme-labeled antibody offers a rapid, sensitive, selective, and simple immunoassay system for future H5 AIV real sample detection. - Keine Nishiyama, Koki Hoshikawa, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiELECTROANALYSIS 31 9 1736 - 1743 2019年09月 [査読有り][通常論文]
A concentric ring array electrode that amplifies the current signal without redox cycling has been developed for highly sensitive electrochemical detection at a single potential in a microfluidic platform. Herein, the effect of ring-electrode width on the current and current density was examined. A ring-array electrode with widths that decrease from the inner to the outer ring was shown to exhibit the highest sensitivity. This electrode delivered a current density that was approximately 50 % higher than that of a conventionally used disc electrode. We used numerical simulations to further optimize this type of array electrode, which led to a limit of detection for catechol of 6.2 nmol/L. This ring array electrode has great potential for use in a variety of applications because it can be used to detect irreversible targets with a simple apparatus at a single potential and requires no electrode modification to achieve high sensitivity. - Mitsue Hibino, Yuma Yamada, Naoki Fujishita, Yusuke Sato, Masatoshi Maeki, Manabu Tokeshi, Hideyoshi HarashimaJOURNAL OF PHARMACEUTICAL SCIENCES 108 8 2668 - 2676 2019年08月 [査読有り][通常論文]
A number of drugs that are currently on the market, as well as new candidates for drugs, are poorly water soluble. Because of this, a need exists to develop drug formulations that will permit the expanded use of such drugs. The use of liposomes and lipid nanoparticles for drug delivery has attracted attention as a technique for solubilizing molecules that are poorly water soluble, but this technique faces serious scale-up risks. In this study, we report on attempts to encapsulate Coenzyme Q(10) (CoQ(10)) as a model of a poorly water-soluble drug in an MITO-Porter, a liposome for mitochondrial delivery using a microfluidic device (a CoQ(10)-MITO-Porter [mu]). The physical properties of the CoQ(10)-MITO-Porter [mu] including homogeneity, size, and preparation volume were compared with those for a CoQ(10)-MITO-Porter prepared by the ethanol dilution method (a CoQ10-MITO-Porter [ED]). In the case where a microfluidic device was used, a small-sized CoQ(10)-MITO-Porter was formed homogeneously, and it was possible to prepare it on a large scale. Intracellular observations using HeLa cells showed that the CoQ(10)-MITO-Porter [mu] was efficiently internalized by cells to reach mitochondria. These results indicate that the CoQ(10)-MITO-Porter [mu] represents a potential candidate for use in mitochondrial nanomedicine. (C) 2019 Published by Elsevier Inc. on behalf of the American Pharmacists Association. - Keine Nishiyama, Toshihiro Kasama, Seiya Nakamata, Koya Ishikawa, Daisuke Onoshima, Hiroshi Yukawa, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Manabu TokeshiANALYST 144 15 4589 - 4595 2019年08月 [査読有り][通常論文]
We present an ultrasensitive immunoassay system for disease biomarkers utilizing the immuno-wall device and an enzymatic amplification reaction. The immuno-wall device consisted of 40 microchannels, each of which contained an antibody-modified wall-like structure along the longitudinal axis of the microchannel. The wall was fabricated with a water-soluble photopolymer containing streptavidin by photolithography, and biotinylated capture antibodies were immobilized on the sides through streptavidin-biotin interaction. For an assay, introducing the target biomarker and secondary and labeled antibodies produced a sandwich complex anchored on the sides of the wall. A conventional immuno-wall device uses a fluorescence-labeled antibody as a labeling antibody. To achieve an ultrasensitive detection of a trace biomarker, we used an enzyme label and amplified the signal with the enzymatic reaction with a fluorogenic substrate in the microchannel. The highest signal/background ratio was obtained by using alkaline phosphatase-labeled antibody and 9H-(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl) phosphate. To evaluate the device performance, we detected human C-reactive protein (CRP) as a model biomarker. The detection limit (LOD) of CRP in phosphate-buffered saline was 2.5 pg mL(-1) with a sample volume of 0.25 mu L. This LOD was approximately 3 orders of magnitude lower than that obtained with fluorescent-dye (DyLight 650)-labeled antibody. In addition, the present device provided a wide detection range of 0.0025-10 ng mL(-1) for CRP. We successfully developed an ultrasensitive immunoassay system with simple operation and only a small sample volume. - Osamu Wakao, Ken Satou, Ayano Nakamura, Polina A. Galkina, Keine Nishiyama, Ken Sumiyoshi, Fumio Kurosawa, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Mikhail A. Proskurnin, Koji Shigemura, Akihide Hibara, Manabu TokeshiLAB ON A CHIP 19 15 2581 - 2588 2019年08月 [査読有り][通常論文]
High-throughput fluorescence polarization immunoassays (FPIAs) for mycotoxin were conducted using a portable FP analyzer with a microdevice. Simultaneous FPIA measurements for 8 different deoxynivalenol (DON) concentrations in 12 chambers (total of 96 samples) and high-throughput FPIA measurements for single DON concentrations in more than 500 chambers were conducted. The results indicated that simultaneous FPIAs for 96 independent samples and for 500 samples were possible by FP imaging. The FP analyzer has a size of 65 cm (W 35 cm x D 15 cm x H 15 cm) and costs less than $5000. The sample volume was 1 nL. Furthermore, it is expected that sample reaction and FP detection can be automatically conducted with the analyzer by changing the microdevice and the software. Its features such as low cost and portability will contribute to on-site measurement and point-of-care testing. Additionally, the high-throughput feature will contribute to the study of molecular interactions based on FP measurements. - Yehezkiel Steven Kurniawan, Mizuki Ryu, Ramachandra Rao Sathuluri, Wataru Iwasaki, Shintaro Morisada, Hidetaka Kawakita, Keisuke Ohto, Masatoshi Maeki, Masaya Miyazaki, JuminaINDONESIAN JOURNAL OF CHEMISTRY 19 2 368 - 375 2019年05月 [査読有り][通常論文]
In this study, the microreactor system was investigated and compared with the batch-wise system as rapid and effective extractive Pb(II) separation over Fe(III), Cu(II) and Zn(II) with tetraacetic acid calix[4]arene. By using a microreactor system, the Pb(II) extraction percentages reached the maximum of 73, 89 and 100% in 8 sec residence time at equilibrium pH of 2.00, 2.25 and 2.50, respectively. The stripping percentage was 92% at 8 sec residence time by using a microreactor system with 2.0 M HNO3 as a stripping reagent. Complete separation of Pb(II) over Fe(III), Cu(II) and Zn(II) ions with the tetraacetic acid calix[4] arene in a competitive metal system was achieved at pH 2.00. However, the batch system required 24 h to reach the equilibrium for both extraction and stripping processes. The results suggested that the microreactor system enhanced the Pb(II) extraction and stripping rate up to 10(4) times faster than the batch-wise system. - Osamu Wakao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu TokeshiSENSORS AND ACTUATORS B-CHEMICAL 285 418 - 422 2019年04月 [査読有り][通常論文]
Fluorescence polarization (FP) is a one of the measurement techniques to study molecular interactions. We previously developed our own FP measurement system based on synchronization detection that uses a liquid crystal layer and an image sensor. The measurement cycle was fixed to 100 without any theoretical considerations, however, the influence of the synchrony and measurement cycles for FP values should be considered. In the present paper, we carried out an experimental and theoretical investigation into the influence of the synchrony between liquid crystal operation and image sampling for FP values of our system. When there was synchronization mismatch, the experimental FP values obtained using fluorescein ethylene glycol solution and the theoretical FP values changed according to the number of measurement cycles. Additionally, we measured the FP immunoassay for a physiologically active substance under synchronization mismatch. The synchronization mismatch influenced the measurement performance of the system, indicating that optimization of the number of image samplings was necessary to improve the measurement performance. For instance, the Mismatch 0.99 case, the measurement cycle should be 50 cycle judging from its dynamic range and R-square (R-2). From the investigation, we obtained theoretical and experimental knowledge on FP response to facilitate further applications of our FP system. - Yusuke Sato, Kazuki Hashiba, Kosuke Sasaki, Masatoshi Maeki, Manabu Tokeshi, Hideyoshi HarashimaJOURNAL OF CONTROLLED RELEASE 295 140 - 152 2019年02月 [査読有り][通常論文]
Lipid nanoparticles (LNPs) are one of the more promising technologies for efficiently delivering short interfering RNA (siRNA) in vivo. A pH-sensitive cationic lipid that facilitates the targeting of hepatocytes and endosomal escape, strongly influences the availability of siRNA, thus making it a key material for efficient siRNA delivery. A systematic knowledge regarding lipid structure-activity relationships would greatly facilitate the development of sophisticated pH-sensitive cationic lipids for use in siRNA-based therapeutics. The systemic derivatization of a hydrophilic head group and hydrophobic tails of YSK12-C4, a pH-sensitive cationic lipid that was developed in our laboratory, revealed that hydrophilic head significantly affected the apparent pKa of the final product, a key factor in both intrahepatic distribution and endosomal escape. The clogP value of a hydrophilic head group was found to be associated with the apparent pKa of the product. In contrast, the hydrophobic tail structure strongly affected intrahepatic distribution without depending on apparent pKa. A structure-activity relationship study enabled the selection of an adequate combination of a hydrophilic head group and hydrophobic tails and permitted a potent LNP composed of a pH-sensitive cationic lipid CL4H6 (CL4H6-LNPs) to be developed that showed efficient gene silencing activity (50% effective dose: 0.0025 mg/kg), biodegradability and was tolerated. In vivo experiments revealed that the CL4H6-LNPs showed a superior efficiency for endosomal escape, cytosolic release and the RNA-induced silencing for the complex-loading of siRNAs compared to the previously developed LNPs. - Donny N. Mazaafrianto, Akihiko Ishida, Masatoshi Maeki, Hirofumi Tani, Manabu TokeshiACS OMEGA 3 12 16823 - 16830 2018年12月 [査読有り][通常論文]
Ochratoxin A (OTA) is one of the most abundant food-contaminating mycotoxins that is also a potential carcinogen and responsible for many diseases affecting humans. Consequently, a sensitive, portable device for the detection of OTA is highly desirable. In this study, a miniaturized electrochemical aptamer-based sensor was developed for the label-free, sensitive detection of OTA. For the construction of the sensor, a gold thin-film three-electrode system was fabricated using standard microfabrication techniques on a polystyrene substrate (25 mm x 25 mm). Subsequently, the thiol-modified linker, 6-mercaptohexanol, DNA aptamer, and methylene blue (MB) were sequentially applied to the working electrode to construct a sensing layer. MB served as a redox indicator that interacted with the aptamer via the guanine bases and phosphate backbone to form complexes. The addition of OTA to the sensor induced the folding of the aptamer, which was accompanied by the release of the aptamer-MB-OTA complex from the sensor. Thus, the amount of MB decreased with increasing concentration of OTA. Differential pulse voltammetry was used for monitoring the highly sensitive detection. The standard curve for OTA exhibited a wide linearity ranging from 0.1 to 300 ng mL(-1) with a detection limit of 78.3 pg mL(-1) (S/N = 3). The selectivity test confirmed that the aptamer had high affinity only for the target. The OTA recoveries with the proposed sensor in commercial samples of coffee and beer were 86.4-107%. - Wataru Iwasaki, Kenichi Yamanaka, Daisuke Sugiyama, Yuki Teshima, Maria Portia Briones-Nagata, Masatoshi Maeki, Kenichi Yamashita, Masashi Takahashi, Masaya MiyazakiSCIENTIFIC REPORTS 8 14273-1 - 14273-9 2018年09月 [査読有り][通常論文]
We fabricated a simple microfluidic device for separation of bovine oocytes based on the oocyte quality to improve the conception rate of in vitro fertilization (IVF) by using good quality oocytes. The microfluidic device separates oocytes based on sedimentation rate differences in a sucrose buffer, which is dependent on oocyte quality. The microfluidic device has a 700 mu m width, 1 mm height, and 10 mm long separation channel. Oocytes were injected from the upper half of the separation channel, and they flowed while sinking. The outlets of the separation channel were divided into upper and lower chambers. Good quality oocytes settled faster than poor quality oocytes in sucrose buffer; therefore, good quality oocytes were collected from the lower outlet. We performed IVF after the microfluidic separation of oocytes. The developmental rate to blastocysts of oocytes collected from the lower outlet was significantly higher than those collected from the upper outlet (36.0% vs. 14.1%). This result was comparable to that in the BCB staining method performed as a comparison method (BCB+ : 35.7%, BCB-: 15.4%). These findings indicate that our microfluidic device could be applied to oocyte separation and contribute to improvement of in vitro embryo production system. - Niko Kimura, Masatoshi Maeki, Yusuke Sato, Yusuke Note, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Manabu TokeshiACS OMEGA 3 5 5044 - 5051 2018年05月 [査読有り][通常論文]
The precise size control of the lipid nanoparticle (LNP)-based nanodrug delivery system (DDS) carriers, such as 10 nm size tuning of LNPs, is one major challenge for the development of next-generation nanomedicines. Size-controlled LNPs would realize size-selective tumor targeting and deliver DNA and RNA to target tumor tissues effectively by passing through the stromal cells. Herein, we developed a baffle mixer device named the invasive lipid nanoparticle production device, or iLiNP device for short, which has a simple two-dimensional microchannel and mixer structure, and we achieved the first reported LNP size tuning at 10 nm intervals in the size range from 20 to 100 nm. In comparison with the conventional LNP preparation methods and reported micromixer devices, our iLiNP device showed better LNP size controllability, robustness of device design, and LNP productivity. Furthermore, we prepared 80 nm sized LNPs with encapsulated small interfering RNA (siRNA) using the iLiNP device; these LNPs effectively performed as nano-DDS carriers in an in vivo experiment. We expect iLiNP devices will become novel apparatuses for LNP production in nano-DDS applications. - Donny Nugraha Mazaafrianto, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiMICROMACHINES 9 5 1 - 25 2018年05月 [査読有り][通常論文]
Since the systematic evolution of ligands by exponential enrichment (SELEX) method was developed, aptamers have made significant contributions as bio-recognition sensors. Microdevice systems allow for low reagent consumption, high-throughput of samples, and disposability. Due to these advantages, there has been an increasing demand to develop microfluidic-based aptasensors for analytical technique applications. This review introduces the principal concepts of aptasensors and then presents some advanced applications of microdevice-based aptasensors on several platforms. Highly sensitive detection techniques, such as electrochemical and optical detection, have been integrated into lab-on-a-chip devices and researchers have moved towards the goal of establishing point-of-care diagnoses for target analyses. - Masatoshi Maeki, Niko Kimura, Yusuke Sato, Hideyoshi Harashima, Manabu TokeshiADVANCED DRUG DELIVERY REVIEWS 128 84 - 100 2018年03月 [査読有り][通常論文]
Lipid-based nanobiomaterials as liposomes and lipid nanoparticles (LNPs) are the most widely used nanocarriers for drug delivery systems (DDSs). Extracellular vesicles (EVs) and exosomes are also expected to be applied as DDS nanocarriers. The performance of nanomedicines relies on their components such as lipids, targeting ligands, encapsulated DNA, encapsulated RNA, and drugs. Recently, the importance of the nanocarrier sizes smaller than 100 nm is attracting attention as a means to improve nanomedicine performance. Microfluidics and lab-on-a chip technologies make it possible to produce size-controlled LNPs by a simple continuous flow process and to separate EVs from blood samples by using a surface marker, ligand, or electric charge or by making a mass or particle size discrimination. Here, we overview recent advances in microfluidic devices and techniques for liposomes, LNPs, and EVs and their applications for DDSs. (C) 2018 Elsevier B.V. All rights reserved. - Osamu Wakao, Ken Satou, Ayano Nakamura, Ken Sumiyoshi, Masanori Shirokawa, Chikaaki Mizokuchi, Kunihiro Shiota, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Koji Shigemura, Akihide Hibara, Manabu TokeshiREVIEW OF SCIENTIFIC INSTRUMENTS 89 2 2018年02月 [査読有り][通常論文]
Fluorescence polarization (FP) offers easy operation and rapid processing, making it implementable in molecular interaction analysis. Previously we have developed a unique FP measurement system using a liquid crystal (LC) layer and an image sensor. The system is based on a principle of synchronized detection between the switching rate of the LC layer and the sampling rate of the CCD. The FP system realized simultaneous multiple sample detection; however, the measurement precision was lower than that of the conventional FP apparatus. The main drawbacks were low light transmittance of the LC layer and insufficient synchronization between the LC layer and CCD. In this paper, we developed a new FP analyzer based on LC-CCD synchronization detection. By using a newly designed LC with high transmittance and improving synchronization, the performance of the system has been dramatically improved. Additionally, we reduced the cost by using an inexpensive CCD and an LED as the excitation source. Simultaneous FP immunoassay of multiple samples of prostaglandin E2 was performed. The error rate of the FP system is reduced from 16.9% to 3.9%, as comparable to the commercial conventional FP system. Published by AIP Publishing. - Takeshi Komatsu, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiANALYTICAL SCIENCES 34 1 39 - 44 2018年01月 [査読有り][通常論文]
We report on the effects of fabrication methods, photolithography, wax printing, screen printing, and craft cutting, on selected properties of microfluidic paper-based analytical devices (mu PADs): cost, fabrication precision, wicking rate, and analytical accuracy. Photolithography requires numerous fabrication steps, and an oxygen plasma treatment is necessary when using an aqueous solution. Although the boundary between the hydrophobic and hydrophilic areas in the mu PAD is sharpest, the obtained K-scale intensity in measuring of protein concentrations is lower than those of the devices by other methods. Wax printing offers the simplest and fastest fabrication, although solution leakage measures should be taken to improve the wicking rate and to prevent cross-contamination. Screen printing also offers easy fabrication. The screen printed mu PAD has a good wicking performance and shows a high detection intensity. Craft cutting allows automated fabrication of many mu PADs at once. The craft cut mu PAD has the fastest wicking rate among the four mu PADs due to bare cellulose fibers. We consider that the detection intensity of this mu PAD can be raised by optimizing the evaporation rate. - Niko Kimura, Masatoshi Maeki, Manabu TokeshiMicrofluidics for Pharmaceutical Applications: From Nano/Micro Systems Fabrication to Controlled Drug Delivery 123 - 136 2018年01月01日Carrier-assist drug delivery systems (DDSs) have been developed to improve the present problems of the cancer chemotherapies. In the developed several types of DDS carriers, lipid nanoparticles (LNPs) are the most widely used for the cancer chemotherapy. Although LNPs have high biocompatibility and good circulation time in blood, precise size control of LNPs in the size range of 20-100 nm is required for the cancer therapy applications. Microfluidic devices will be key apparatus to achieve the size-controlled LNP synthesis. A microfluidic device with micromixer structures also plays important role for the LNP production, because it enables rapid mixing of lipid solution and aqueous solution for precise LNP size control. This chapter provides the microfluidic-based LNP production methods from the device fabrication to DDS applications.
- Ramachandra Rao Sathuluri, Yehezkiel Steven Kurniawan, Jee Young Kim, Masatoshi Maeki, Wataru Iwasaki, Shintaro Morisada, Hidetaka Kawakita, Masaya Miyazaki, Keisuke OhtoSEPARATION SCIENCE AND TECHNOLOGY 53 8 1261 - 1272 2018年 [査読有り][通常論文]
Stepwise recovery of silver(I), palladium(II) and platinum(IV) with suitable calix[4]arene extractants was carried out by investigating the extraction and stripping process using a droplet-based microreactor system. The highest percentages of silver, palladium (100%) and platinum ion (37.2%) were extracted from a real waste only within 4.00s using a microreactor system compared with 24 and 72h to reach extraction equilibrium in a batch method. Fourier transform infrared spectroscopy studies revealed a very good relation in peak shifts on the metal complexation with calix[4]arene derivatives after extraction and stripping. The droplet-based microreactor system emerges as an effective tool to be applied in metal recovery. - Masatoshi Maeki, Yuka Fujishima, Yusuke Sato, Takao Yasui, Noritada Kaji, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Hideyoshi Harashima, Manabu TokeshiPLOS ONE 12 11 e0187962-1 - e0187962-16 2017年11月 [査読有り][通常論文]
Lipid nanoparticles (LNPs) or liposomes are the most widely used drug carriers for nanomedicines. The size of LNPs is one of the essential factors affecting drug delivery efficiency and therapeutic efficiency. Here, we demonstrated the effect of lipid concentration and mixing performance on the LNP size using microfluidic devices with the aim of understanding the LNP formation mechanism and controlling the LNP size precisely. We fabricated microfluidic devices with different depths, 11 mu m and 31 mu m, of their chaotic micromixer structures. According to the LNP formation behavior results, by using a low concentration of the lipid solution and the microfluidic device equipped with the 31 mu m chaotic mixer structures, we were able to produce the smallest-sized LNPs yet with a narrow particle size distribution. We also evaluated the mixing rate of the microfluidic devices using a laser scanning confocal microscopy and we estimated the critical ethanol concentration for controlling the LNP size. The critical ethanol concentration range was estimated to be 60-80% ethanol. Ten nanometer-sized tuning of LNPs was achieved for the optimum residence time at the critical concentration using the microfluidic devices with chaotic mixer structures. The residence times at the critical concentration necessary to control the LNP size were 10, 15-25, and 50 ms time-scales for 30, 40, and 50 nm-sized LNPs, respectively. Finally, we proposed the LNP formation mechanism based on the determined LNP formation behavior and the critical ethanol concentration. The precise size-controlled LNPs produced by the microfluidic devices are expected to become carriers for next generation nanomedicines and they will lead to new and effective approaches for cancer treatment. - Taiga Ajiri, Haruya Kasa, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Junji Nishi, Manabu TokeshiANALYTICAL SCIENCES 33 10 1197 - 1199 2017年10月 [査読有り][通常論文]
Recently, we developed a label-free detection method based on optical diffraction, and implemented it in on our fabricated micro- and nanofluidic device. This detection method is simple and useful for detecting biomolecules, but the device fabrication consists of complicated processes. In this paper, we propose a simple method for fabricating the micro- and nanofluidic device; the fabrication combines laser interference lithography with conventional photolithography. The performance of a device fabricated by the proposed method is comparable to the performance of the device in our previous study. - Taiga Ajiri, Takao Yasui, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Manabu TokeshiSENSORS AND ACTUATORS B-CHEMICAL 250 39 - 43 2017年10月 [査読有り][通常論文]
Single-molecule detection of the biomolecules in a label-free manner has a tremendous impact for various fields. Recently, we developed a label-free detection method without any pretreatment procedures, which is based on optical diffraction derived from a nanofluidic channel array (in other words, a nanowall array). However, the single-molecule detection is hampered by the inherent sensitivity of the method. We propose a solution to improve the sensitivity of the method by adjusting the height of the nanowall array. Numerical simulations showed that a larger nanowall array height could provide better sensitivity, but a lower nanowall array height could provide better sensitivity difference, contrary to what we would intuitively expect. We used a 250 nm height nanowall array to achieve a label-free detection of 0.18 DNA molecules to verify the simulation prediction. These results demonstrate our method has a potential to be implemented in a highly sensitive refractometer with small sample consumption. (C) 2017 Elsevier B.V. All rights reserved. - Droplet-Based Microreactor System for Stepwise Recovery of Precious Metal Ions from Real Metal Waste with Calix[4]arene DerivativesR. R. Sathuluri, Y. Steven, J. Y. Kim, M. Maeki, W. Iwasaki, S. Morisada, H. Kawakita, M. Miyazaki, K. OhtoSepar. Sci. Technol. 52 1 - 12 2017年09月 [査読有り][通常論文]
- Saeed Mohammadi, Lori Shayne Alamo Busa, Masatoshi Maeki, Reza M. Mohamadi, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiANALYTICAL SCIENCES 32 12 1359 - 1362 2016年12月 [査読有り][通常論文]
We demonstrated a rapid immunoassay for detection of cat cystatin C (cCys-C) which is an important marker for chronic kidney disease in cats, using immuno-pillar chips. The required amount of reagent solution is 200 times smaller than that for the conventional ELISA in the 96-well microplate (0.5 mu L versus 100 mu L). In addition, the total assay time in the proposed method is more than 12 times shorter than in the conventional method (20 min versus 240 min). The limit of detection in the new method of 3 ng mL(-1) is comparable to that of the conventional method (1 ng mL(-1)) and it is in the clinically relevant range. - Saeed Mohammadi, Lori Shayne Alamo Busa, Masatoshi Maeki, Reza M. Mohamadi, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiANALYTICAL AND BIOANALYTICAL CHEMISTRY 408 27 7559 - 7563 2016年11月 [査読有り][通常論文]
A novel washing technique for microfluidic paper-based analytical devices (mu PADs) that is based on the spontaneous capillary action of paper and eliminates unbound antigen and antibody in a sandwich immunoassay is reported. Liquids can flow through a porous medium (such as paper) in the absence of external pressure as a result of capillary action. Uniform results were achieved when washing a paper substrate in a PDMS holder which was integrated with a cartridge absorber acting as a porous medium. Our study demonstrated that applying this washing technique would allow mu PADs to become the least expensive microfluidic device platform with high reproducibility and sensitivity. In a model mu PAD assay that utilized this novel washing technique, C-reactive protein (CRP) was detected with a limit of detection (LOD) of 5 mu g mL(-1). - Lori Shayne Alamo Busa, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiSENSORS AND ACTUATORS B-CHEMICAL 236 433 - 441 2016年11月 [査読有り][通常論文]
This article describes the development of a simple, portable assay system using microfluidic paper-based analytical devices (mu PADs) coupled with colorimetric detection for rapid measurements. The properties of different paper substrates were first investigated to determine which type of paper would be the most suitable for the fabrication of the mu PADs. Simultaneous detection of horseradish peroxidase (HRP) utilizing a 5 mu L sample analytical volume was demonstrated using a single mu PAD. Hydrophilic test regions were separated by hydrophobic barriers, which were fabricated through photolithography. These test regions were immobilized with 10 mM of 3,3',5,5'-tetramethylbenzidine for HRP assay. The detection range obtained with the proposed system covered HRP concentrations from 0.37 to 124 fmol (or 31000 ng mL(-1)). The detection limit (blank + 3 sigma) for HRP was calculated to be 0.69 fmol (or 5.58 ng mL(-1)) through a 4-parameter logistic nonlinear regression using results obtained within a 15 min assay time. The findings obtained using the developed system suggest that mu PAD assay systems for simple but highly sensitive measurements can be designed to give on-site determinations of target compounds using peroxidase-conjugated molecules. ((c)) 2016 Elsevier B.V. All rights reserved. - Lori Shayne, Alamo Busa, Takeshi Komatsu, Saeed Mohammadi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiAnalytical Sciences 32 8 815 - 818 2016年08月 [査読有り][通常論文]
We report on the colorimetric oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by hydrogen peroxide using horseradish peroxidase on photolithography-fabricated (P-PAD) and wax-printed (W-PAD) paper-based analytical devices. Fabricating PADs via photolithography exposes the hydrophilic areas to polymers (photoresists) and solvents, not only reducing the hydrophilicity, but also affecting the TMB-H2O2 assay system with an unavoidable incomplete elimination of photoresist during fabrication. Detection signals are then observed in the presence of photoresist residues on the P-PAD, even at a blank HRP concentration. - Lori Shayne Alamo Busa, Saeed Mohammadi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiMICROMACHINES 7 5 1 - 21 2016年05月 [査読有り][通常論文]
Food and water contamination cause safety and health concerns to both animals and humans. Conventional methods for monitoring food and water contamination are often laborious and require highly skilled technicians to perform the measurements, making the quest for developing simpler and cost-effective techniques for rapid monitoring incessant. Since the pioneering works of Whitesides' group from 2007, interest has been strong in the development and application of microfluidic paper-based analytical devices (PADs) for food and water analysis, which allow easy, rapid and cost-effective point-of-need screening of the targets. This paper reviews recently reported PADs that incorporate different detection methods such as colorimetric, electrochemical, fluorescence, chemiluminescence, and electrochemiluminescence techniques for food and water analysis. - Yusuke Sato, Yusuke Note, Masatoshi Maeki, Noritada Kaji, Yoshinobu Baba, Manabu Tokeshi, Hideyoshi HarashimaJOURNAL OF CONTROLLED RELEASE 229 48 - 57 2016年05月 [査読有り][通常論文]
Because nanoparticles with diameters less than 50 nm penetrate stromal-rich tumor tissues more efficiently, the synthesis of small-sized nanoparticles encapsulating short interfering RNA (siRNA) is important in terms of realizing novel siRNA medicine for the treatment of various cancers. Lipid nanoparticles (LNPs) are the leading systems for the delivery of siRNA in vivo. Limit size LNPs were successfully synthesized using a microfluidic mixing technique. However, the physicochemical properties and potential for in vivo siRNA delivery of the limit-size LNPs have not been examined in detail. In the present study, we prepared LNPs with different diameters from 32 to 67 nm using a microfluidic mixing devise and examined the physicochemical properties of the particles and the potential for their use in delivering siRNA in vitro and in vivo to liver. Reducing the size of the LNPs causes poor-packing and an increased surface area, which result in their instability in serum. Moreover, it was revealed that the ability of endosomal escape (cytosolic siRNA release) of the smaller LNPs is subject to inhibition by serum compared to that of larger counterparts. Taken together, an increase in packing and avoiding the adsorption of serum components are key strategies for the development of next-generation highly potent and small-sized LNPs. (C) 2016 Elsevier B.V. All rights reserved. - Lori Shayne Alamo Busa, Saeed Mohammadi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiANALYST 141 24 6598 - 6603 2016年 [査読有り][通常論文]
The development of a competitive immunoassay system for colorimetric detection on microfluidic paper-based analytical devices (mu PADs) is reported. The mu PADs were fabricated via photolithography to define hydrophilic flow channels and consisted of three main elements: the control and test zones, where target detection was performed, the sample introduction zone, and the competitive capture zone located between the sample introduction zone and the test zone. The chromogenic substrate 3,3', 5,5'-tetra-methylbenzidine (TMB) was deposited at the control and test zones. mu PAD surface modification was performed at the capture zone first via chitosan activation, then the BSA-conjugated target compound was immobilized. The sample solution consisting of the target compound, the peroxidase-conjugated antibody, and the hydrogen peroxide oxidizing agent was introduced into the device and competition occurred at the capture zone, allowing only the target-bound peroxidase-conjugated antibody to travel past the capture zone and into the test zone via capillary action. The developed competitive immunoassay system was successfully demonstrated on the mu PAD detection of biotin as a model compound with a detection limit of 0.10 mu g mL(-1). The applicability of the proposed immunoassay system for point-of-need testing was further demonstrated using aflatoxin B-1, a highly toxic foodborne substance, with a detection limit of 1.31 ng mL(-1). The mu PAD with the competitive immunoassay format showed promising results for practical applications in point-of-need testing involving small molecular weight targets in food and water safety and quality monitoring, environmental analysis, and clinical diagnostics. - Takeshi Komatsu, Saeed Mohammadi, Lori Shayne Alamo Busa, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiANALYST 141 24 6507 - 6509 2016年 [査読有り][通常論文]
The combination of a microfluidic paper-based analytical device (mu PAD) and digital image analysis is widely used for quantitative analysis with mu PADs because of its easy and simple operation. Herein, we have demonstrated a quantitative analysis based on multiple color changes on a mu PAD. The CIE L*a*b* color system was employed to analyse the digital images obtained with the mu PAD. We made pH measurements using a universal pH-indicator showing multiple color changes for various pH values of aqueous test solutions. The detectable pH range of this method was wider than the typical grayscale-based image analysis, and we succeeded in the measurements for a wide pH range of 2-9. - Masatoshi Maeki, Shohei Yamazaki, Ashtamurthy S. Pawate, Akihiko Ishida, Hirofumi Tani, Kenichi Yamashita, Masakazu Sugishima, Keiichi Watanabe, Manabu Tokeshi, Paul J. A. Kenis, Masaya MiyazakiCRYSTENGCOMM 18 40 7722 - 7727 2016年 [査読有り][通常論文]
Protein crystallization and subsequent X-ray diffraction analysis of the three-dimensional structure are necessary for elucidation of the biological functions of proteins and effective rational drug design. Therefore, controlling protein crystallization is important to obtain high resolution X-ray diffraction data. Here, a simple microfluidic method using chips with 10 and 50 mu m high crystallization chambers to selectively form suitable single protein crystals for X-ray analysis is demonstrated. As proof of concept, three different types of proteins: lysozyme, glucokinase from Pseudoalteromonas sp. AS-131 (PsGK), and NADPH-cytochrome P450 oxidoreductase-heme oxygenase complex were crystallized. We demonstrate that the crystal growth orientation depends on the height of the crystallization chamber regardless of the protein type. Our results suggest that the confined micro space induces the protein molecules to adhere to a specific crystal face and affects the growth kinetics of each crystal face. The present microfluidic-based protein crystallization method can reform a suitable single protein crystal for X-ray analysis from aggregates of needle-shaped protein crystals. - Masatoshi Maeki, Hiroshi Yamaguchi, Manabu Tokeshi, Masaya MiyazakiANALYTICAL SCIENCES 32 1 3 - 9 2016年01月 [査読有り][通常論文]
This review summarizes two microfluidic-based protein crystallization methods, protein crystallization behavior in the microfluidic devices, and their applications for X-ray crystal structure analysis. Microfluidic devices provide many advantages for protein crystallography; they require small sample volumes, provide high-throughput screening, and allow control of the protein crystallization. A droplet-based protein crystallization method is a useful technique for high-throughput screening and the formation of a single crystal without any complicated device fabrication process. Well-based microfluidic platforms also enable effective protein crystallization. This review also summarizes the protein crystal growth behavior in microfluidic devices as, is known from viewpoints of theoretical and experimental approaches. Finally, we introduce applications of microfluidic devices for on-chip crystal structure analysis. - Osamu Wakao, Yusaku Fujii, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu TokeshiANALYTICAL CHEMISTRY 87 19 9647 - 9652 2015年10月 [査読有り][通常論文]
The detection system which enables simultaneous fluorescence polarization (FP) measurement of multiple samples was proposed and proven by a proof-of-concept experiment on the viscosity dependence of FP of fluorescein sample in water-ethylene glycol solution and another experiment on the FP immunoassay of prostaglandin E2 sample. The measurement principle of FP is based on the synchronization between the orientation of the liquid crystal molecules and the sampling frequency of a CCD. This report is the first description of the simultaneous FP measurement of multiple samples. This system has a great potential for equipment miniaturization and price reduction as well as providing simultaneous FP measurement of multiple samples. - Masatoshi Maeki, Ashtamurthy S. Pawate, Kenichi Yamashita, Masahide Kawamoto, Manabu Tokeshi, Paul J. A. Kenis, Masaya MiyazakiANALYTICAL CHEMISTRY 87 8 4194 - 4200 2015年04月 [査読有り][通常論文]
We demonstrate a seamless and contactless method from protein crystallization to X-ray analysis using a microfluidic chip with the aim of obtaining a complete crystallographic data set of a protein crystal under cryogenic conditions. Our microfluidics-based approach did not require direct manipulation of the protein crystal. Therefore, the microfluidic chip approach is suitable for novices of X-ray analysis of protein crystals. We also investigated the effect of stepwise cryoprotection on the quality of protein crystals. Protein crystals with cryoprotection via on-chip manipulation did not show deterioration of crystallographic quality of the protein crystal. The complete diffraction data set of a protein crystal, which is required for determining the 3D structure of the target protein, is obtainable by a simple manipulation. - Masatoshi Maeki, Tatsuyoshi Saito, Yusuke Sato, Takao Yasui, Noritada Kaji, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Hideyoshi Harashima, Manabu TokeshiRSC ADVANCES 5 57 46181 - 46185 2015年 [査読有り][通常論文]
Formation behavior of lipid nanoparticles (LNPs) in microfluidic devices with a staggered herringbone micromixer (SHM) structure was investigated. The fundamental role for SHMs in LNP formation was demonstrated by determining such factors as the limiting SHM cycle numbers and the effect of flow rate. The SHM cycle numbers and the position of the first SHM were as significant as factors as the flow rate condition for producing the small-size LNPs. - Saeed Mohammadi, Masatoshi Maeki, Reza M. Mohamadi, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiANALYST 140 19 6493 - 6499 2015年 [査読有り][通常論文]
This paper describes a simple and instrument-free screen-printing method to fabricate hydrophilic channels by patterning polydimethylsiloxane (PDMS) onto chromatography paper. Clearly recognizable border lines were formed between hydrophilic and hydrophobic areas. The minimum width of the printed channel to deliver an aqueous sample was 600 mu m, as obtained by this method. Fabricated microfluidic paper-based analytical devices (mu PADs) were tested for several colorimetric assays of pH, glucose, and protein in both buffer and artificial urine samples and results were obtained in less than 30 min. The limits of detection (LODs) for glucose and bovine serum albumin (BSA) were 5 mM and 8 mu M, respectively. Furthermore, the pH values of different solutions were visually recognised with the naked eye by using a sensitive ink. Ultimately, it is expected that this PDMS-screen-printing (PSP) methodology for mu PADs can be readily translated to other colorimetric detection and hydrophilic channels surrounded by a hydrophobic polymer can be formed to transport fluids toward target zones. - Keisuke Ohto, JeeYoung Kim, Shintaro Morisada, Masatoshi Maeki, Kenichi Yamashita, Masaya MiyazakiInternational Journal of the Society of Material Engineering for Resources 20 1 92 - 96 2014年04月01日 [査読有り][通常論文]
Extraction reagents based on p-t-octylcalix[4]arene with ketonic and 2-pyridyl groups were prepared to investigate extraction behavior of precious metal ions by using microreactor system. Although the ketonic derivative exhibited high silver selectivity in nitric acid media, it took for more than 72 h to reach extraction equilibrium. On the contrary, the extraction rate was drastically improved by using microreactor system. It took for 16 s to extract silver ion by using parallel two phases flow type microreactor. The silver extraction rate was further improved by using slug flow type microreactor to be within 4 s. The extraction rate for ketonic derivative was much more improved compared with that for 2-pyridyl one. One of the reasons why silver extraction rate was drastically improved by using microreactor system was attributed to the enhanced interfacial area. It was supported by the result for the interfacial tension measurement of two extraction reagents. - Masatoshi Maeki, Yuta Hatanaka, Kenichi Yamashita, Masaya Miyazaki, Keisuke OhtoSOLVENT EXTRACTION RESEARCH AND DEVELOPMENT-JAPAN 21 77 - 82 2014年 [査読有り][通常論文]
In this study, the extraction behavior of calixarene derivatives by using the multiphase parallel flow technique was investigated. Using a partially-modified microfluidic device, the extraction rate of silver and palladium ions from the aqueous phase with calix[4]arene derivatives was evaluated. As a result, the time necessary for silver ion to reach equilibrium was 15 s. In the case of palladium extraction, the extraction percentage was 80 % at 8 s reaction time. In the conventional batch method, the times necessary for silver and palladium extraction to reach equilibria were about 72 h and 5 min, respectively. These results showed that increasing the liquid-liquid interface area is effective in the solvent extraction of metal ions with calix[4]arene derivatives. The correlation between the difference in the functional groups of calix[4]arenes and their effect on the rate of extraction at the parallel flow liquid-liquid interface was considered. - Daisuke Sugiyama, Yuki Teshima, Kenichi Yamanaka, Maria Portia Briones-Nagata, Masatoshi Maeki, Kenichi Yamashita, Masashi Takahashi, Masaya MiyazakiANALYTICAL METHODS 6 1 308 - 311 2014年 [査読有り][通常論文]
We investigate the behaviour of a simple microfluidic device designed to separate particles based on density. The device consists of a separation-channel with three inlet and two outlet channels. The particle samples were loaded in the middle of the main channel. The results of separation experiments using model particles provide clear evidence that this approach can be used to achieve good separation of particles of close density populations. Particle separation was found more favourable with low flow rates. Forces exerted on particles were modelled by Stokes' law and found to be consistent with experimental results. One advantage of this microfluidic system is low exposure of the sample to hydrodynamic shear stresses compared with conventional methods. This device may be adopted to precisely handle single cells and easily interface with other tools and separation techniques. - Masatoshi Maeki, Yuki Teshima, Saori Yoshizuka, Hiroshi Yamaguchi, Kenichi Yamashita, Masaya MiyazakiCHEMISTRY-A EUROPEAN JOURNAL 20 4 1049 - 1056 2014年01月 [査読有り][通常論文]
Herein, we demonstrate the potential of droplet-based microfluidics for controlling protein crystallization and generating single-protein crystals. We estimated the critical droplet size for obtaining a single crystal within a microdroplet and investigated the crystallization of four model proteins to confirm the effect of protein molecular diffusion on crystallization. A single crystal was obtained in microdroplets smaller than the critical size by using droplet-based microfluidics. In the case of thaumatin crystallization, a single thaumatin crystal was obtained in a 200m droplet even with high supersaturation. In the case of ferritin crystallization, the nucleation profile of ferritin crystals had a wider distribution than the nucleation profiles of lysozyme, thaumatin, and glucose isomerase crystallization. We found that the droplet-based microfluidic approach was able to control the nucleation of a protein by providing control over the crystallization conditions and the droplet size, and that the diffusion of protein molecules is a significant factor in controlling the nucleation of protein crystals in droplet-based microfluidics. - Atsushi Maruyama, Naotaka Sonda, Kohei Yamasaki, Masanori Hirano, Satoru Kidoaki, Naohiko Shimada, Masatoshi Maeshiro, Masaya MiyazakiCURRENT NANOSCIENCE 10 2 185 - 188 2014年 [査読有り][通常論文]
The interaction of a single molecule of DNA with cationic comb-type copolymers has been observed using a flow-stretch assay. We have shown that interaction with a copolymer with a high degree of grafting did not cause a coil-to-globule transition but resulted in shrinkage of the DNA by 20%. In this study, a flow-stretch assay was employed in which changes in length and fluorescence intensity of DNA were simultaneously observed. Upon binding of fluorescent intercalator dyes, the DNA length was extended. In the presence of copolymer, dye binding was inhibited and DNA length was not significantly different than that in the absence of dye and copolymer. Our data suggest that the copolymer does not influence DNA length. Our observation implies that use of the fluorescence dye exclusion assay to estimate DNA condensing activity of polycations must be carefully carried out. - Hiroshi Yamaguchi, Masatoshi Maeki, Kenichi Yamashita, Hiroyuki Nakamura, Masaya Miyazaki, Hideaki MaedaJOURNAL OF BIOCHEMISTRY 153 4 339 - 346 2013年04月 [査読有り][通常論文]
The preparation of a single crystal is important for a detailed understanding of the structure of protein. However, the preparation of a suitable crystal for X-ray diffraction is often a drawback due to the complexity of the protein molecules and the limited fundamental understanding of the protein crystallization mechanism. In this study, we studied the crystallization mechanism in droplet that was prepared by the microfluidic chip. We found that the mechanism of crystal growth in droplet is different from that by a conventional microbatch method. One crystal was grown in one droplet by controlling droplet shape and droplet volume. In addition, the surface area in droplet affected the size of the obtained protein crystal and the number of crystal(s). The growth of the (110) and (101) faces of tetragonal crystal could be determined by studying one crystal formed within one droplet, indicating that the observation and evaluation of one crystal growth kinetics is easily carried out compared with the conventional method. - Yuki Teshima, Masatoshi Maeki, Kenichi Yamashita, Masaya MiyazakiCRYSTENGCOMM 15 46 9874 - 9877 2013年 [査読有り][通常論文]
This paper explores the selective crystallization of a metastable phase and the possible role played by the internal fluid dynamics characteristic of microdroplets. The density-driven convection is suppressed inside the microdroplets due to its high surface tension. It is suggested that as a consequence, this lowered the solute concentration at the area near the growing crystal. This phenomenon is thought to suppress the second crystallization near the first grown crystal and the transition from a thermodynamically metastable phase to a stable phase. - Masatoshi Maeki, Saori Yoshizuka, Hiroshi Yamaguchi, Masahide Kawamoto, Kenichi Yamashita, Hiroyuki Nakamura, Masaya Miyazaki, Hideaki MaedaANALYTICAL SCIENCES 28 1 65 - 68 2012年01月 [査読有り][通常論文]
We describe the technical aspects of the in-situ X-ray diffraction of a protein crystal prepared by a nanodroplet-based crystallization method. We were able to obtain diffraction patterns from a crystal grown in a capillary without any manipulation. Especially in our experimental approach, the crystals that moved to the nanodroplet interface were fixed strongly enough to carry out X-ray diffraction measurements that could be attributed to the high surface tension of the nanodroplet. The crystal was damaged by an indirect action of the X-rays because our in-situ X-ray diffraction measurement was carried out in the liquid phase without freezing the crystal; however, the obtained several diffraction patterns were of sufficiently fine quality for the crystal structure factors to be generated. We consider the technical examination presented in this paper to represent a seamless coupling of crystallization to X-ray analysis. - Masatoshi Maeki, Hiroshi Yamaguchi, Kenichi Yamashita, Hiroyuki Nakamura, Masaya Miyazaki, Hideaki MaedaCHEMICAL COMMUNICATIONS 48 41 5037 - 5039 2012年 [査読有り][通常論文]
The single crystallization method by focusing on the characteristic internal fluid dynamics of the microdroplets was explored. Also the theoretical background was discussed, and the droplet size for obtaining only a single crystal within a microdroplet was estimated. - Satoshi Nitahara, Masatoshi Maeki, Hiroshi Yamaguchi, Kenichi Yamashita, Masaya Miyazaki, Hideaki MaedaANALYST 137 24 5730 - 5735 2012年 [査読有り][通常論文]
Confocal Raman spectroscopic imaging has been used to find the location of protein crystals deposited in a nanodroplet. The depth of the protein crystal has been clearly identified by comparing the three-dimensional Raman spectroscopic images of the protein with those of water. Additionally, the low concentration region around a growing protein crystal in the nanodroplet was visualized using two-dimensional Raman spectroscopic imaging. - Masatoshi Maeki, Hiroshi Yamaguchi, Kenichi Yamashita, Hiroyuki Nakamura, Masaya Miyazaki, Hideaki MaedaCHEMISTRY LETTERS 40 8 825 - 827 2011年08月 [査読有り][通常論文]
This paper demonstrates the possibility of controlling nucleation and crystal growth behavior within a droplet formed in a microspace. The effects of droplet volume and shape were examined by using thaumatin as a model system. The droplet size and shape affected the number and size of the obtained protein crystals.
書籍
- マイクロ流体分析渡慶次学, 真栄城正寿, 佐藤記一, 佐藤香枝, 火原彰秀, 石田晃彦 (担当:共著範囲:2章、6-3章)
共立出版 2020年10月 - Applications of Microfluidic Systems in Biology and MedicineMasatoshi Maeki, Manabu Tokeshi (担当:共著範囲:Chapter 2 “Microfluidics Technologies and Platforms for Protein Crystallography”)
Springer Nature 2019年 - Microfluidics for Pharmaceutical ApplicationsMasatoshi Maeki (担当:共著範囲:Microfluidic Production of Multicomponent Multiple Emulsions)
Elsevier 2018年 123-136 - 機能紙最前線 〜次世代機能紙とその垂直連携に向けて〜真栄城正寿, 渡慶次学 (担当:分担執筆範囲:紙を使った分析・診断チップの現状と可能性)
加工技術研究会
講演・口頭発表等
- マイクロ流体デバイスを用いた脂質ナノ粒子の作製と核酸送達に向けた構造解析 [招待講演]真栄城正寿物構研コロキウム 2024年01月 口頭発表（招待・特別）
- Production of lipid nanoparticles using microfluidic devices and its application to genome delivery [招待講演]真栄城正寿第97回日本薬理学会年会 2023年12月 口頭発表（招待・特別）
- Microfluidic Devices for Biomimetic Nanoparticles [招待講演]Masatoshi MaekiNanoBioTech Montreux Conference 2023年11月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いた人工エクソソーム作製と核酸送達への応用 [通常講演]真栄城正寿, 丹羽彩由花, 大山祥大, 荒谷響子, 日比野光恵, 石田晃彦, 渡慶次学第10回日本細胞外小胞学会学術集会 2023年10月 ポスター発表
- Development of Artificial Exosomes Using a Microfluidic Device for RNA Delivery [通常講演]Masatoshi Maeki, Ayuka Niwa, Shota Oyama, Akihiko Ishida, Manabu TokeshiThe 27th International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2023) 2023年10月 ポスター発表
- 蛍光ナノダイヤモンド搭載 脂質ナノ粒子の開発と量子計測への応用 [招待講演]真栄城正寿第9回北大・部局横断シンポジウム 2023年10月 口頭発表（招待・特別）
- 人工エクソソームDDSの可能性 [招待講演]真栄城正寿第14回 日本RNAi研究会 2023年09月 口頭発表（招待・特別）
- 手のひらサイズの 化学プラント・医療診断装置 [招待講演]真栄城正寿夢・化学-21 化学への招待 「北海道大学化学系への二日体験入学」 2023年08月 口頭発表（招待・特別）
- Development of Microfluidic Devices for Lipid Nanoparticle Production [招待講演]Masatoshi MaekiKBCS-Hokkaido University Joint Symposium on BioChip Technology 2023年06月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いた脂質・エクソソーム様ナノ粒子作製と 核酸送達への応用 [通常講演]真栄城 正寿, 渡慶次 学化学とマイクロ・ナノシステム学会 第 47 回研究会 2023年05月 ポスター発表
- Structure dynamics measurement of lipid nanoparticles using a microfluidic device [招待講演]Masatoshi MaekiPITTCON Conference & Expo 2023 2023年03月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いた時分割測定技術の開発 [招待講演]真栄城正寿令和4年度 新学術領域研究「高速分子動画」シンポジウム 2022年11月 口頭発表（招待・特別）
- マイクロ流路を基盤とした脂質ナノ粒子製造技術の開発 [招待講演]真栄城正寿第33回クロマトグラフィー科学会議（SCS33） 2022年11月 口頭発表（招待・特別）
- Development of microfluidic devices for structural dynamics measurement of biomolecules [招待講演]Masatoshi Maeki第60回日本生物物理学会年会 2022年09月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いた脂質ナノ粒子の連続大量製造技術の開発とGMP機開発への取り組み [招待講演]真栄城正寿第27回創剤フォーラム 第27回若手研究会 2022年09月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いた脂質ナノ粒子製造装置の開発 [招待講演]真栄城正寿日本機械学会 2022年度年次大会 2022年09月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いた人工エクソソームの開発と診断・創薬への応用 [招待講演]真栄城正寿SAITAS DAYS 2022年09月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いた脂質ナノ粒子製造技術 [招待講演]真栄城正寿日本薬学会北海道支部主催講演会 2022年01月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いた脂質ナノ粒子作製と分析化学への応用 [招待講演]真栄城正寿キャピラリー電気泳動シンポジウム（SCE2021） 2021年12月 口頭発表（招待・特別）
- Protein-ligand complex structure analysis using a microfluidic device [招待講演]Masatoshi MaekiMIRAI 2.0 Materials Science TEG Workshop 2021年12月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いた脂質ナノ粒子製造プロセスの開発 [招待講演]真栄城正寿第7回北大・部局横断シンポジウム 2021年10月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いた脂質ナノ粒子作製とRNA送達への応用 [招待講演]真栄城正寿化学工学会 第52回秋季大会若手シンポジウム 2021年09月 口頭発表（招待・特別）
- マイクロ化学デバイスを用いた脂質ナノ粒子作製技術と核酸医薬への応用 [招待講演]真栄城正寿第34回岡山マイクロリアクターネット例会 2021年07月 口頭発表（招待・特別）
- 構造生物学における測定・解析の自動化とマイクロデバイスの応用 [招待講演]真栄城正寿第81回分析化学討論会 2021年05月 口頭発表（招待・特別）
- マイクロ流体デバイスを用いたDDSナノ粒子作製法の開発 [招待講演]真栄城正寿一般社団法人近畿化学協会合成部会フロー・マイクロ合成研究会 第89回研究会 2021年03月 口頭発表（招待・特別）
- 機能集積化マイクロ化学デバイスの開発と医薬分野への展開 [招待講演]真栄城正寿２０２０年度 日本化学会北海道支部奨励賞 受賞講演 2021年02月 口頭発表（招待・特別）
- 脂質ナノ粒子分離のためのナノ構造体デバイスの開発 [通常講演]清水一樹, 真栄城正寿, 石田晃彦, 谷博文, 西井準治, 渡慶次学化学系学協会北海道支部2021年冬季研究発表会 2021年01月 口頭発表（一般）
- ナノ構造体搭載デバイスによる脂質ナノ粒子のサイズ分離 [通常講演]清水一樹, 真栄城正寿, 石田晃彦, 谷博文, 西井準治, 渡慶次学化学とマイクロナノシステム学会 第42回研究会（CHEMINAS42） 2020年10月 ポスター発表
- マイクロデバイスを用いたタンパク質結晶の室温構造解析 [通常講演]竹田怜央, 真栄城正寿, 伊藤翔, 上野剛, 石田晃彦, 谷博文, 山本雅貴, 渡慶次学化学とマイクロナノシステム学会 第42回研究会（CHEMINAS42） 2020年10月 ポスター発表
- Production of sub-20 nm polymeric particles for drug delivery enabled by a microfluidic device [通常講演]Yi Bao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu Tokeshi化学とマイクロナノシステム学会 第42回研究会（CHEMINAS42） 2020年10月 ポスター発表
- Microfluidic assisted preparation of a PLGA based drug delivery system [通常講演]BAO Yi, Maeki Masatoshi, Ishida Akihiko, Tani Hirofumi, Tokeshi Manabu第10回CSJ化学フェスタ 2020年10月 ポスター発表
- マイクロ流体デバイスを用いた脂質ナノ粒子作製法の開発と核酸医薬への応用 [招待講演]真栄城正寿第6回北大部局横断シンポジウム 2020年10月 口頭発表（招待・特別）
- An Aprotic Polar Solvent Assisted Size-Tuning Method for Microfluidic Production of Lipid-Based Drug Nanocarriers with Various Sizes [通常講演]Niko Kimura, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiThe 24th International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2020) 2020年10月 ポスター発表
- ガラス製マイクロ流体デバイスを用いたsiRNA搭載脂質ナノ粒子の作製と 大量生産用集積化デバイスの開発 [通常講演]岡田悠斗, 真栄城正寿(登壇者), 佐藤悠介, 石田晃彦, 谷博文, 原島秀吉, 渡慶次学第36回日本DDS学会学術集会 2020年08月 ポスター発表
- ナノ構造体を用いた脂質ナノ粒子のサイズ分離 [通常講演]清水 一樹, 真栄城 正寿, 石田 晃彦, 谷 博文, 渡慶次 学第80回分析化学討論会 2020年05月 口頭発表（一般）
- 常温X線結晶構造解析のためのマイクロデバイスの開発舟久保 智瑛, 真栄城 正寿, 伊藤 翔, 上野 剛, 石田 晃彦, 谷 博文, 山本 雅貴, 渡慶次 学第80回分析化学討論会 2020年05月 口頭発表（一般）
- Lipid Nanoparticles Separation Using a Nanopillar Device [通常講演]Shimizu K, Maeki M, Ishida A, Tani H, Nishii J, Tokeshi MBio4Apps 2019 2019年12月 ポスター発表
- 核酸搭載脂質ナノ粒子の動的構造解析 [通常講演]真栄城正寿、木村笑、清水一樹、石田晃彦、谷博文、渡慶次学化学とマイクロ・ナノシステム学会 第40回研究会 2019年11月 ポスター発表
- Development of the Separation Method of Nanoparticles Using a Micro-Nano Device [通常講演]Shimizu K, Maeki M, Ishida A, Tani H, Nishii J, Tokeshi32nd International Microprocesses and nanotechnology Conference (MNC2019) 2019年10月 ポスター発表
- UNDERSTANDING THE LIPID NANOPARTICLES STRUCTURE DYNAMICS USING A TIME-RESOLVED SAXS MEASUREMENT [通常講演]Masatoshi Maeki, Niko Kimura, Kazuki Shimizu, Kento Yonezawa, Nobutaka Shimizu, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiThe 23rd International Conference on Miniaturized Systems for Chemistry and Life Sciences（MicroTAS 2019） 2019年10月 ポスター発表
- Development of a Three-Dimensional Micromixer Device for Production of Various Lipid-Based Nucleic Acid Nanocarriers [通常講演]Kimura N, Maeki M, Sato Y, Sasaki K, Ishida A, Tani H, Harashima H, Tokeshi MThe 23rd International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2019) 2019年10月 ポスター発表
- 小角X線溶液散乱法による脂質ナノ粒子の動的構造解析法の開発 [通常講演]真栄城正寿, 木村 笑, 石田 晃彦, 谷 博文, 渡慶次 学日本分析化学会第68年会 2019年09月 口頭発表（一般）
- マイクロデバイスによるタンパク質の立体構造解析 [招待講演]真栄城 正寿PAI-NET マーケットトレンドセミナー 「マイクロフルイディクスの実用化」 2019年09月 公開講演，セミナー，チュートリアル，講習，講義等
- マイクロデバイスを用いたタンパク質-リガンド複合体構造解析 [通常講演]真栄城正寿, 竹田怜央, 伊藤翔, 上野剛, 平田邦生, 石田晃彦, 谷博文, 山本 雅貴, 渡慶次学第79回分析化学討論会 2019年05月 口頭発表（一般）
- Preparation of PLGA Nanoparticles by Using a Microfluidic PlatformYi B, Maeki M, Kimura N, Ishida A, Tani H, Tokeshi MThe 11th International Symposium on Microchemistry and Microsystems 2019年05月 ポスター発表
- 時間分解X線溶液散乱による脂質ナノ粒子の形成メカニズムの解明 [招待講演]真栄城 正寿北大-KEK連携協力協定 第9回連携シンポジウム 2019年03月 口頭発表（招待・特別）
- Precise Size Tuning of Lipid Nanoparticles Using Baffle Mixer Devices [招待講演]真栄城 正寿PITTCON Conference & Expo 2019 2019年03月 口頭発表（招待・特別）
- マイクロデバイスを用いた脂質ナノ粒子の時間分解SAXS測定 [招待講演]真栄城 正寿PF研究会「多様な物質・生命科学研究に広がる小角散乱 〜 多（他）分野の小角散乱を学ぼう！」 2018年12月 シンポジウム・ワークショップパネル（指名）
- マイクロ流体デバイスを用いた脂質ナノ粒子調製と薬物送達システムへの応用 [招待講演]真栄城 正寿ECCウェルネス共同研究講座 キックオフシンポジウム 2018年09月 シンポジウム・ワークショップパネル（公募）
- DDS ナノキャリア製造のためのマイクロデバイスの開発 [通常講演]真栄城 正寿NanoBio 第 11 回若手ネットワーキングシンポジウム 2018年06月 口頭発表（一般）
- IN-SITU MEASUREMENT OF GROWTH RATE OF PROTEIN CRYSTAL IN MICORFLUIDIC DEVICES [通常講演]Masatoshi Maeki, Shohei Yamazaki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiThe 10th International Symposium on Microchemistry and Microsystems (ISMM2016) 2018年06月 ポスター発表
- マイクロデバイスを用いたタンパク質の結晶化と構造解析への応用 [招待講演]真栄城 正寿第21回XFEL構造生物ミーティング 2018年03月 シンポジウム・ワークショップパネル（指名）
- マイクロデバイスによるDDSナノキャリア作製法の開発 [招待講演]真栄城 正寿日本表面科学会東北北海道支部 2017年度講演会 2018年03月 口頭発表（招待・特別）
- マイクロデバイスによるタンパク質の結晶化制御と構造解析への応用 [招待講演]真栄城 正寿2017年 第1回水和ナノ構造研究会 2017年10月 口頭発表（招待・特別）
- マイクロ・ナノデバイスによる生体分子のオンチップ測定 [招待講演]真栄城 正寿第10回レーザー学会 「レーザーバイオ医療」技術専門委員会 2017年09月 口頭発表（招待・特別）
- マイクロ・ナノデバイスを用いた生体分子測定法の開発と応用 [招待講演]真栄城 正寿第35回九州分析化学会若手の会 夏季セミナー 2017年07月 口頭発表（招待・特別）
- Microfluidic-based Production of Lipid Nanoparticles for DDS Applications [招待講演]真栄城 正寿23rd Pharmascience Forum 2017年03月 口頭発表（招待・特別）
- マイクロデバイスを用いたタンパク質の立体構造解析法の開発 [招待講演]真栄城 正寿北海道分析化学奨励賞 受賞講演 2017年01月 口頭発表（招待・特別）
- マイクロ流体デバイスにおける脂質ナノ粒子のサイズ制御の解明 [通常講演]藤島由佳, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学化学系学協会北海道支部2017年冬季研究発表会 2017年01月 口頭発表（一般）
- Development of a Fluorescence Polarization-based High-Throughput System for Molecular Interaction Screening [通常講演]Osamu Wakao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu TokeshiThe 29th International Microprocesses and Nanotechnology Conference（MNC 2016） 2016年11月 ポスター発表
- Development of a New Technique for Washing Steps in Multistep Assays Using Microfluidic Paper-based Analytical Devices [通常講演]Saeed Mohammadi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiThe 20th International Conference on Miniaturized Systems for Chemistry and Life Sciences（MicroTAS 2016）, Dublin（Ireland） 2016年10月 ポスター発表
- Fluorescence Polarization-based Multiple Samples Detection Using Microchamber Array Towards High-throughput Molecular Interaction Analysis [通常講演]Osamu Wakao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu TokeshiThe 20th International Conference on Miniaturized Systems for Chemistry and Life Sciences（MicroTAS 2016） 2016年10月 ポスター発表
- Effect of the Grooved Structures and the Ethanol Concentration on the Small-sized Lipid Nanoparticles Formation [通常講演]Yuka Fujishima, Masatoshi Maeki, Yusuke Sato, Takao Yasui, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Hideyoshi Harashima, Manabu TokeshiThe 20th International Conference on Miniaturized Systems for Chemistry and Life Sciences（MicroTAS 2016） 2016年10月 ポスター発表
- 紙をベースとした食品検査チップの開発 [通常講演]真栄城正寿, 渡慶次学グリーンテクノバンク Unmet needs ワークショップ 2016年10月 シンポジウム・ワークショップパネル（指名）
- がん診断のためのエクソソーム分析法の開発 [通常講演]阿尻大雅, 安井隆雄, 真栄城正寿, 石田晃彦, 谷博文, 馬場嘉信, 渡慶次学日本分析化学会第65年会 2016年09月 口頭発表（一般）
- マイクロチップ電機化学検出ＬＣデバイスの生体試料への応用 [通常講演]藤井大地, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学日本分析化学会第65年会 2016年09月 口頭発表（一般）
- 血中リチウム濃度測定のためのペーパーデバイスの開発 [通常講演]小松雄士, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学日本分析化学会第65年会 2016年09月 口頭発表（一般）
- 機能集積化マイクロ分析デバイスの開発と医薬学分野への応用 [招待講演]真栄城 正寿日本分析化学会第65年会 2016年09月 口頭発表（招待・特別）
- Controlling Protein Crystallization for X-ray Crystal Structure Analysis Using Microfluidic Device [招待講演]真栄城 正寿日本分析化学会第65年会 第3回アジア分析科学シンポジウム 2016年09月 口頭発表（招待・特別）
- Development of a Multifunctional Micro-Nano device for Cancer Diagnosis [通常講演]Taiga Ajiri, Takao Yasui, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Manabu TokeshiThe 7th Japan-China-Korea Joint Conference on MEMS/NEMS 2016 2016年09月 口頭発表（一般）
- Fluorescence Polarization Imaging for Bioanalysis Using a Liquid Crystal and an Imaging Sensor [通常講演]Osamu Wakao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu TokeshiThe 7th Japan-China-Korea Joint Conference on MEMS/NEMS 2016 2016年09月 口頭発表（一般）
- Development of Molecular Interactions Analysis System by Fluorescence Polarization Imaging [通常講演]Osamu Wakao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu TokeshiRSC Tokyo International Conference 2016 2016年09月 ポスター発表
- Lipid Nanoparticle Formation Behavior in Microfluidic Chips and Its Application for Nanomedicine [通常講演]Masatoshi Maeki, Yuka Fujishima, Yusuke Sato, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Manabu TokeshiRSC Tokyo International Conference 2016 2016年09月 ポスター発表
- マイクロデバイスを用いたタンパク質の結晶化 [通常講演]真栄城 正寿北海道大学工学系イノベーションフォーラム2016 2016年09月 ポスター発表
- PDMS製チップホルダーを用いたペーパーマイクロ分析チップの開発 [通常講演]Saeed Mohammadi, Lori S. A. Busa, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学化学とマイクロ・ナノシステム学会 第34回研究会 2016年09月 ポスター発表
- マイクロデバイスを用いたタンパク質の立体構造解析 [招待講演]真栄城 正寿第2回北海道ナノバイオ（HNB）シンポジウム 2016年08月 シンポジウム・ワークショップパネル（指名）
- 高感度化を目指したイムノアッセイデバイスの開発 [通常講演]中股征哉, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学北海道支部2016年夏季研究発表会 2016年07月 口頭発表（一般）
- マイクロ流体デバイスを用いた化学発光イムノアッセイシステムの開発 [通常講演]菊地優仁, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学北海道支部2016年夏季研究発表会 2016年07月 口頭発表（一般）
- マイクロ流体デバイスを用いたリゾチームの結晶成長制御 [通常講演]山崎翔平, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学北海道支部2016年夏季研究発表会 2016年07月 口頭発表（一般）
- 血中リチウムイオン濃度測定のためのペーパーデバイスの開発 [通常講演]小松雄士, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学第３２回分析化学緑陰セミナー 2016年06月 ポスター発表
- マイクロ流体デバイスを用いた化学発光イムノアッセイシステムの開発 [通常講演]菊地優仁, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学第32回分析化学緑陰セミナー 2016年06月 ポスター発表
- Preparation of Liquid Nanoparticles Using a Microfluidic Device [通常講演]Masatoshi Maeki, Yuka Fujishima, Yusuke Sato, Takao Yasui, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Hideyoshi Harashima, Manabu TokeshiThe 8th International Symposium on Microchemistry and Microsystems (ISMM2016) 2016年05月 ポスター発表
- Development of Fluorescence Polarization Measurement System Toward Molecular Interaction Analysis [通常講演]Osamu Wakao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu TokeshiThe 8th International Symposium on Microchemistry and Microsystems (ISMM2016) 2016年05月 ポスター発表
- Fluoroimmunoassay of Cat Cystatin C Using a Paper-Based Microfluidic Device [通常講演]Saeed Mohammadi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiThe 8th International Symposium on Microchemistry and Microsystems (ISMM2016) 2016年05月 ポスター発表
- マイクロデバイスによるタンパク質の立体構造解析 [通常講演]真栄城正寿, 山崎翔平, 杉島正一, 渡邉啓一, 石田晃彦, 谷博文, 宮崎真佐也, 渡慶次学第76回分析化学討論会 2016年05月 口頭発表（一般）
- 分子間相互間作用測定のための蛍光偏光イメージングシステムの開発 [通常講演]若尾摂, 真栄城正寿, 石田晃彦, 谷博文, 火原彰秀, 渡慶次学第76回分析化学討論会 2016年05月 口頭発表（一般）
- マイクロデバイスを用いたクロラムフェニコールの蛍光偏光免疫測定 [通常講演]青木琴, 若尾摂, 真栄城正寿, 石田晃彦, 谷博文, Sergei Eremin, 渡慶次学化学とマイクロ・ナノシステム学会 第33回研究会 2016年04月 ポスター発表
- マイクロ流体制御によるタンパク質立体構造解析システムの開発 [招待講演]真栄城 正寿化学とマイクロ・ナノシステム学会 第33回研究会 2016年04月 口頭発表（招待・特別）
- Microfluidic-based approach for producing diffraction quality protein crystals [招待講演]真栄城正寿, Ashtamurthy Pawate, 杉島正一, 渡邉啓一, 渡慶次学, Paul J. A. Kenis, 宮崎真佐也Pittcon2016 2016年03月 口頭発表（招待・特別）
- がん診断のためのエクソソームの無標識検出 [通常講演]阿尻大雅, 安井隆雄, 石田晃彦, 谷博文, 真栄城正寿, 馬場嘉信, 渡慶次学化学系学協会北海道支部2016年冬季研究発表会 2016年01月 口頭発表（一般）
- ルシフェラーゼ内封リポソームを用いたオンチップイムノアッセイ [通常講演]中谷友祐, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学化学系学協会北海道支部2016年冬季研究発表会 2016年01月 口頭発表（一般）
- 蛍光偏光イメージングによる複数サン プルの同時イムノアッセイ [通常講演]若尾摂, 真栄城正寿, 石田晃彦, 谷博文, 火原彰秀, 渡慶次 学化学系学協会北海道支部2016年冬季研究発表会 2016年01月 口頭発表（一般）
- ATP測定のための電気化学酵素センサーの開発 [通常講演]西山慶音, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学化学系学協会北海道支部2016年冬季研究発表会 2016年01月 口頭発表（一般）
- Liposome immunoassay based on bioluminescent detection and its application to on-chip analysis [通常講演]Y. Nakatani, M. Maeki, R. Mishra, D. King, A. Ishida, J. Ducrée, M. Tokeshi, H. TaniPACIFIC BASIN SOCIETIES 2015 2015年12月 ポスター発表
- Paper-based fluoroimmunoassay for rapid and sensitive detection of an animal biomarker [通常講演]Saeed Mohammadi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiPACIFIC BASIN SOCIETIES 2015 2015年12月 ポスター発表
- Microfluidic paper-based devices for aflatoxin B1 analysis [通常講演]Lori A. Busa, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiPACIFIC BASIN SOCIETIES 2015 2015年12月 ポスター発表
- Fluorescence polarization imaging for analyzing molecular interactions [通常講演]Osamu Wakao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu TokeshiPACIFIC BASIN SOCIETIES 2015 2015年12月 ポスター発表
- Formation mechanism of lipid nanoparticles in microchannels [通常講演]Yuka Fujishima, Masatoshi Maeki, Takao Yasui, Yusuke Sato, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Yoshinobu Baba, Manadu TokeshiPACIFIC BASIN SOCIETIES 2015 2015年12月 ポスター発表
- Simple method for the preparation of high diffraction quality protein crystals using microfluidic device [通常講演]Masatoshi Maeki, Ashtamurhy S. Pawate, Masakazu Sugishima, Keiichi Watanabe, Manabu Tokeshi, Paul J.A.Kenis, Masaya MiyazakiPACIFIC BASIN SOCIETIES 2015, ANYL803 2015年12月 ポスター発表
- 脂質ナノ粒子の粒径制御のためのマイクロ流体デバイス設計 [通常講演]真栄城正寿, 藤島由佳, 佐藤悠介, 石田晃彦, 谷博文, 原島秀吉, 渡慶次学化学とマイクロ・ナノシステム学会 第32回研究会 2015年11月 ポスター発表
- Microfluidic Paper-based Lateral-flow Detection System for Aflatoxin B1 [通常講演]Lori Shayne, Alamo Busa, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiThe 3rd International Life-Science Symposium 2015年11月 口頭発表（一般）
- Patterned paper enables bio and chemical sensing via screen-printing technique [通常講演]Saeed Mohammadi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu TokeshiThe 3rd International Life-Science Symposium 2015年11月 口頭発表（一般）
- Microfluidic Approach for Production of Lipid Nanoparticles-Based Nano Medicine [通常講演]Masatoshi Maeki, Tatsuyoshi Saito, Yusuke Sato, Takao Yasui, Noritada Kaji, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Hideyoshi Harashima, Manabu TokeshiThe 19th International Conference on Miniaturized Systems for Chemistry and Life Sciences(MicroTAS2015) 2015年10月 ポスター発表
- Fluorescence Polarization Imageing for Multisample Immunoassay [通常講演]Osamu Wakao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu TokeshiThe 19th International Conference on Miniaturized Systems for Chemistry and Life Sciences(MicroTAS2015) 2015年10月 ポスター発表
- Droplet-based Microreactor System for an Efficient Recovery of Rare Metal Ions with Calix[4]arene Derivatives from Acidic Media [通常講演]Ramachandra R. Sathuluri, Masatoshi Maeki, Yuki Ueda, Jee Y. Kim, Keisuke Ohto, Masaya MiyazakiAPCChE 2015 Congress incorporating Chemeca 2015 2015年09月 口頭発表（一般）
- Development of Microfluidic Device for Protein Crystallization and Its Application for X-ray Analysis [招待講演]真栄城正寿, Ashtamurthy Pawate, 杉島正一, 渡邉啓一, 渡慶次学, Paul J. A. Kenis, 宮崎真佐也The 6th Japan-Chica-Korea Joint Conference on MEMS/NEMS 2015 2015年09月 口頭発表（招待・特別）
- An Approach for Controlling Epitaxial Growth of Protein Crystal by Using Microfluidic Device [通常講演]Masatoshi Maeki, Ashtamurthy S. Pawate, Masakazu Sugishima, Keiichi Watanabe, Manabu Tokeshi, Paul J. A. Kenis, Masaya MiyazakiFifth European Conference on Crystal Growth (ECCG 5) 2015年09月 ポスター発表
- マイクロ流体デバイスを用いたドラッグデリバリーシステムのための脂質ナノ粒子の作製 [通常講演]藤島由佳, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学遺伝子・デリバリー研究会 第１５回夏季セミナー 2015年09月 口頭発表（一般）
- マイクロ流路内における脂質ナノ粒子形成の可視化 [通常講演]藤島由佳, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学日本化学会北海道支部2015年夏季研究大会 2015年07月 口頭発表（一般）
- マイクロ流体デバイスを用いた脂質ナノ粒子の作製と形成挙動の可視化 [通常講演]藤島由佳, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学第31回緑陰セミナー 2015年06月 ポスター発表
- Protein Crystal Growth in Confined Space of Microfluidic Device [通常講演]Masatoshi Maeki, Ashtamurhy S. Pawate, Masakazu Sugishima, Keiichi Watanabe, Manabu Tokeshi, Paul J.A.Kenis, Masaya Miyazaki7th International Symposium on Microchemistry and Microsystes (ISMM2015) 2015年06月 ポスター発表
- Visualization of Lipid Nanoparticles Formation in Microchannels [通常講演]Yuka Fujisima, Masatoshi Maeki, Takao Yasui, Yusuke Sato, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Yoshinobu Baba, Manabu Tokeshi7th International Symposium on Microchemistry and Microsystes (ISMM 2015) 2015年06月 ポスター発表
- A Screen-Printed Paper-Based Device for Chemical Sensing [通常講演]Saeed Mohammadi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu Tokeshi7th International Symposium on Microchemistry and Microsystems (ISMM 2015)7th International Symposium on Microchemistry and Microsystems (ISMM 2015) 2015年06月 ポスター発表
- Liposome Formation Behavior in Microfluidic Device [通常講演]Masatoshi Maeki, Tatsuyoshi Saito, Takao Yasui, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Manabu TokeshiISPlasma 2015 2015年03月 口頭発表（一般）
- マイクロ流体デバイスを用いた作製法におけるリポソームの形成挙動 [通常講演]齋藤 竜亮, 真栄城正寿, 安井隆雄, 石田晃彦, 谷博文, 馬場嘉信, 渡慶次学化学系学協会北海道支部2015年冬季研究発表会 2015年01月 口頭発表（一般）
- Liposome Formation by Mixing in Microfluidic Device with Mixer Structures [通常講演]Tatsuyoshi Saito, Masatoshi Maeki, Takao Yasui, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Manabu Tokeshi14th Asia-Pacific International Symposium on Microscale Separations and Analysis 2014年12月 ポスター発表
- Microfluidic-Based Approach for the Formation of Nanoscale Lipid Particles [通常講演]Masatoshi Maeki, Tatsuyoshi Saito, Takao Yasui, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Manabu TokeshiThe 17th Hokkaido University- Seoul National University Joint symposium Satellite Session “Frontiers in Pharmaceuticals Science and Nanotechnology” 2014年11月 口頭発表（一般）
- マイクロ流体デバイスによるタンパク質の結晶化制御技術 [通常講演]真栄城正寿, Ashtamurthy S. Pawate, 渡邉啓一, 渡慶次学, Paul J, A. Kenis, 宮崎真佐也平成26年度 日本結晶学会年会 2014年11月 ポスター発表
- Crystal Habit Modification of Protein by Using Microfluidic Chip [通常講演]Masatoshi Maeki, Ashtamurhy S. Pawatw, Keiichi Watanabe, Manabu Tokeshi, Paul J. A. Kenis, Masaya MiyazakiThe 18th International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS2014) 2014年10月 ポスター発表
- マイクロ流路内におけるリポソーム形成メカニズムの考察 [通常講演]齋藤竜亮, 真栄城正寿, 安井隆雄, 石田晃彦, 谷博文, 馬場嘉信, 渡慶次学化学とマイクロ・ナノシステム学会第30回研究会 2014年10月 ポスター発表
- A Simple Method of PDMS Hydrophobic Barrier for Fabrication of Hydrophilic Microchannels on Paper [通常講演]Saeed Mohammadi, Maeki Masatoshi, Akihiko Ishida, Hirofumi Tani, Manabu Tokeshi化学とマイクロ・ナノシステム学会第30回研究会 2014年10月 ポスター発表
- Fabrication of Paper-Based Device for Aflatoxin B1 Immunoassay [通常講演]Lori Shayne, Alamo Busa, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu Tokeshi化学とマイクロ・ナノシステム学会第30回研究会 2014年10月 ポスター発表
- 微小液滴を用いたカリックスアレーン誘導体による金属抽出システムの構築 [通常講演]真栄城正寿, Jee Young Kim, Sathuluri R. Rao, 上田祐生, 大渡啓介, 宮崎真佐也化学工学会 第46回秋季大会 2014年09月 口頭発表（一般）
- Application of Microreactor System in Solvent Extraction of Metal Ion with Calixarene derivatives [通常講演]Masatoshi Maeki, Jee Young Kim, Masaya Miyazaki, Keisuke Ohto20th International Solvent Extraction Conference 2014 (ISEC2014) 2014年09月 ポスター発表
- A Method of Effective Cryoprotection for X-ray Analysis of Protein Crystal by Using Microfluidic Chip [通常講演]Masatoshi Maeki, Ashtamurhy S. Pawatw, Kenichi Yamashita, Masahide Kawamoto, Keiichi Watanabe, Manabu Tokeshi, Paul J. A. Kenis, Masaya MiyazakiThe 6th International Symposium on Microchemistry and Microsystems (ISMM2014) 2014年07月 ポスター発表
- Efficient Recovery of metal ion with calixarene derivatives by using microreactor system [通常講演]Masatoshi Maeki, Jee Young Kim, Masaya Miyazaki, Keisuke Ohto13th International Conference on MicroReaction Technology (IMRET13) 2014年06月 ポスター発表
- マイクロ流路を用いたタンパク質結晶の晶癖制御 [通常講演]真栄城正寿, Ashtamurthy Pawate, 渡邉啓一, 渡慶次学, Paul. J, A. Kenis, 宮崎真佐也化学とマイクロ・ナノシステム学会第29回研究会 2014年05月 ポスター発表
- マイクロ空間を用いる晶析制御 [招待講演]真栄城正寿化学工学会 マイクロ化学プロセス分科会討論交流会 2013年07月 口頭発表（招待・特別）
その他活動・業績
- 日比野光恵, 日比野光恵, 真栄城正寿, 渡慶次学, 原島秀吉, 山田勇磨 日本薬剤学会年会講演要旨集(CD-ROM) 38th 2023年
- 杉原崚太, 日比野光恵, 真栄城正寿, 渡慶次学, 中村孝司, 原島秀吉, 山田勇磨 生体膜と薬物の相互作用シンポジウム講演要旨集 44th 2023年
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- 野呂田楓, 石塚宣, 廣瀬みさ, 真栄城正寿, 渡慶次学, 原島秀吉, 山田勇磨, 山田勇磨 日本薬学会年会要旨集(Web) 143rd 2023年
- 真栄城正寿, 真栄城正寿, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集(CD-ROM) 47th 2023年
- 青木駿典, 金沢貴憲, 金沢貴憲, 飯岡真吾, 照喜名孝之, 真栄城正寿, 渡慶次学, 近藤啓 日本DDS学会学術集会プログラム予稿集 39th 2023年
- 日比野光恵, 真栄城正寿, 渡慶次学, 原島秀吉, 山田勇磨 日本DDS学会学術集会プログラム予稿集 39th 2023年
- 真栄城正寿 ぶんせき (10) 2023年
- 野呂田楓, 野呂田楓, 野呂田楓, 石塚宣, 廣瀬みさ, 真栄城正寿, 渡慶次学, 原島秀吉, 山田勇磨 日本DDS学会学術集会プログラム予稿集 39th 2023年
- 長縄莉奈, 高野勇太, 高野勇太, 趙韓俊, 真栄城正寿, 渡慶次学, 原島秀吉, 山田勇磨 日本DDS学会学術集会プログラム予稿集 39th 2023年
- 川口彰太, 安井隆雄, 安井隆雄, 安井隆雄, 嶋田泰佑, 神谷由紀子, 浅沼浩之, 真栄城正寿, 渡慶次学, 古賀大尚, 村上正晃, 馬場嘉信, 馬場嘉信, 馬場嘉信 化学とマイクロ・ナノシステム学会研究会講演要旨集(CD-ROM) 47th 2023年
- 川口彰太, 安井隆雄, 安井隆雄, 安井隆雄, 嶋田泰佑, 神谷由紀子, 浅沼浩之, 真栄城正寿, 渡慶次学, 古賀大尚, 村上正晃, 馬場嘉信, 馬場嘉信, 馬場嘉信 日本化学会春季年会講演予稿集(Web) 103rd 2023年
- 才木陸朗, 石田晃彦, 真栄城正寿, 谷博文, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集(CD-ROM) 46th 2022年
- 杉浦魁星, 真栄城正寿, 真栄城正寿, 佐藤悠介, 石田晃彦, 谷博文, 原島秀吉, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集(CD-ROM) 45th 2022年
- 丹羽彩由花, 大山祥大, 真栄城正寿, 真栄城正寿, 石田晃彦, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集(CD-ROM) 46th 2022年
- 一町田由貴, 真栄城正寿, 真栄城正寿, 上野剛, 小西真昌, 坂井直樹, 石田晃彦, 谷博文, 山本雅樹, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集(CD-ROM) 45th 2022年
- 宇野秀哉, 真栄城正寿, 真栄城正寿, 佐藤悠介, 石田晃彦, 原島秀吉, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集(CD-ROM) 46th 2022年
- 川口彰太, 安井隆雄, 安井隆雄, 安井隆雄, 嶋田泰佑, 神谷由紀子, 浅沼浩之, 真栄城正寿, 渡慶次学, 古賀大尚, 村上正晃, 馬場嘉信, 馬場嘉信, 馬場嘉信 化学とマイクロ・ナノシステム学会研究会講演要旨集(CD-ROM) 46th 2022年
- 伊藤啓太, 真鍋良幸, 真鍋良幸, 大島志乃, 亀谷美恵, 真栄城正寿, 渡慶次学, 樺山一哉, 樺山一哉, 深瀬浩一, 深瀬浩一 日本ワクチン学会学術集会プログラム・抄録集 26th 2022年
- 日比野光恵, 山田勇磨, 真栄城正寿, 渡慶次学, 原島秀吉 日本薬学会年会要旨集(Web) 142nd 2022年
- 伊藤百, 山田勇磨, 山田勇磨, 日比野光恵, 佐々木大輔, 真栄城正寿, 渡慶次学, 渡慶次学, 太田善浩, 原島秀吉, 原島秀吉 日本薬学会年会要旨集(Web) 142nd 2022年
- 白石真大, 白石真大, 山田勇磨, 山田勇磨, 佐々木大輔, 日比野光恵, 真栄城正寿, 渡慶次学, 武田充人, 原島秀吉 日本DDS学会学術集会プログラム予稿集 38th 2022年
- ミトコンドリア人工共生による細胞機能制御の試み山田 勇磨, 日比野 光恵, 伊藤 百, 荒井 愛永, 佐々木 大輔, 真栄城 正寿, 渡慶次 学, 太田 善浩, 原島 秀吉 日本DDS学会学術集会プログラム予稿集 37回 111 -111 2021年06月
- 宇野秀哉, 真栄城正寿, 真栄城正寿, 佐藤悠介, 石田晃彦, 谷博文, 原島秀吉, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 43rd 2021年
- 千田駿亮, 高橋和希, 福山真央, 粕谷素洋, 真栄城正寿, 石田晃彦, 谷博文, ZHERDEV Anatoly V., EREMIN Sergei A., EREMIN Sergei A., 火原彰秀, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集(CD-ROM) 44th 2021年
- 高橋和希, 福山真央, 粕谷素洋, 真栄城正寿, 石田晃彦, 谷博文, 火原彰秀, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集(CD-ROM) 44th 2021年
- 山田勇磨, 山田勇磨, 日比野光恵, 伊藤百, 荒井愛永, 佐々木大輔, 真栄城正寿, 渡慶次学, 渡慶次学, 太田善浩, 原島秀吉, 原島秀吉 日本薬剤学会年会講演要旨集(CD-ROM) 36th 2021年
- 中村孝司, 河合美典, 佐藤悠介, 真栄城正寿, 渡慶次学, 原島秀吉 日本薬剤学会年会講演要旨集(CD-ROM) 36th 2021年
- 真栄城正寿 中谷医工計測技術振興財団年報 (34) 2021年
- 飯岡真吾, 日比野光恵, 山田勇磨, 真栄城正寿, 渡慶次学, 照喜名孝之, 金沢貴憲, 近藤啓 日本薬学会年会要旨集(Web) 141st 2021年
- 真栄城正寿 ホソカワ粉体工学振興財団年報(Web) 28 2021年
- 後藤悠太, 山田勇磨, 日比野光恵, 佐々木大輔, 武田充人, 真栄城正寿, 渡慶次学, 原島秀吉 日本薬学会年会要旨集(Web) 141st 29V09 -pm09S 2021年
- 脂質ナノ粒子の特性がリンパ節送達とリンパ節内分布へ与える影響中村 孝司, 河合 美典, 佐藤 悠介, 真栄城 正寿, 渡慶次 学, 原島 秀吉 日本薬剤学会年会講演要旨集 35年会 171 -171 2020年05月
- 高橋和希, 西山慶音, 福山真央, 粕谷素洋, 真栄城正寿, 石田晃彦, 谷博文, 火原彰秀, 渡慶次学 キャピラリー電気泳動シンポジウム講演要旨集 40th (CD-ROM) 2020年
- 清水一樹, 真栄城正寿, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学 分析化学討論会講演要旨集(Web) 80th 2020年
- 前田陵我, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学 分析化学討論会講演要旨集(Web) 80th 2020年
- 小松雄士, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学 分析化学討論会講演要旨集(Web) 80th 2020年
- 西村卓馬, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学 分析化学討論会講演要旨集(Web) 80th 2020年
- 野中康伸, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学 分析化学討論会講演要旨集(Web) 80th 2020年
- 舟久保智瑛, 真栄城正寿, 真栄城正寿, 伊藤翔, 伊藤翔, 上野剛, 石田晃彦, 谷博文, 山本雅貴, 渡慶次学 分析化学討論会講演要旨集(Web) 80th 2020年
- 高田一生, 渡慶次学, 谷博文, 石田晃彦, 真栄城正寿 分析化学討論会講演要旨集(Web) 80th 2020年
- 西山慶音, RAMOS Kenia Chavez, 真栄城正寿, 石田晃彦, 谷博文, 笠間敏博, 馬場嘉信, 渡慶次学 分析化学討論会講演要旨集(Web) 80th 2020年
- 九鬼静香, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学 分析化学討論会講演要旨集(Web) 80th 2020年
- Keine Nishiyama, Yohei Takeda, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Koji Shigemura, Akihide Hibara, Haruko Ogawa, Manabu Tokeshi MicroTAS 2020 - 24th International Conference on Miniaturized Systems for Chemistry and Life Sciences 1226 -1227 2020年This paper reports a high-throughput and rapid method for a fluorescence polarization immunoassay (FPIA) of H5-avian influenza virus (H5-AIV) and anti-H5-AIV antibody using a portable FP analyzer with a microdevice. For both assays, a fluorescein-labeled recombinant fragment of H5-hemagglutinin was prepared. Although the labeled fragment had low molecular-weight, it served as a tracer for the FPIA. Also, a microdevice having multiplex microchannels was designed, allowing simultaneous multiplex analysis at a small sample volume. Consequently, the virus and the antibody in several samples were successfully detected rapidly in the same format.
- 小松雄士, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学 日本化学会春季年会講演予稿集(CD-ROM) 100th 2020年
- 前田陵我, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 42nd (Web) 2020年
- 清水一樹, 真栄城正寿, 真栄城正寿, 石田晃彦, 谷博文, 西井準治, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 42nd (Web) 2020年
- 中村孝司, 河合美典, 佐藤悠介, 真栄城正寿, 渡慶次学, 原島秀吉 日本薬学会年会要旨集(CD-ROM) 140th (Web) 26X -am10 2020年
- 佐藤悠介, 鈴木裕一, 小沼はるの, 佐藤里咲, 真栄城正寿, 渡慶次学, 原島秀吉 日本DDS学会学術集会プログラム予稿集 36th 162 -162 2020年
- 日比野光恵, 山田勇磨, 真栄城正寿, 渡慶次学, 石塚洋一, 原島秀吉 日本DDS学会学術集会プログラム予稿集 36th 163 -163 2020年
- 真栄城正寿, 真栄城正寿, 岡田悠斗, 佐藤悠介, 石田晃彦, 谷博文, 原島秀吉, 渡慶次学 日本DDS学会学術集会プログラム予稿集 36th 191 -191 2020年
- 岡田悠斗, 真栄城正寿, 真栄城正寿, 佐藤悠介, 石田晃彦, 谷博文, 原島秀吉, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 42nd (Web) 2020年
- 竹田怜央, 真栄城正寿, 真栄城正寿, 伊藤翔, 伊藤翔, 上野剛, 石田晃彦, 谷博文, 山本雅貴, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 42nd (Web) 2020年
- Niko Kimura, Masatoshi Maeki, Yusuke Note, Yusuke Sato, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Manabu Tokeshi 21st International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2017 965 -966 2020年 [査読有り][通常論文]
© 17CBMS-0001. This paper reports a lipid nanoparticles (LNP) production method and its formation behavior using microfluidic devices with baffle structures. The microfluidic devices showed great mixing efficiency at 500 μL/min, and we achieved 20 nm-sized LNPs production that chaotic micromixers were not able to produce at the same flow rate condition. Additionally, we found that the smaller-sized LNPs/siRNA prepared by baffle structures have higher penetration efficiency than that of the larger-sized LNPs, but all of them showed the gene silencing activity. The microfluidic devices with baffle structures are expected to be a practicable apparatus for DDSs application. - Osamu Wakao, Ken Sumiyoshi, Chikaaki Mizokuchi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Koji Shigemura, Akihide Hibara, Manabu Tokeshi 21st International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2017 557 -558 2020年 [査読有り][通常論文]
© 17CBMS-0001. This report demonstrated simultaneous fluorescence polarization (FP) measurement for 100 samples. The measurement was based on the synchronization detection between the switching of a liquid crystal (LC) layer and the sampling rate of an image sensor. This offered captured FP signals from multisample as single FP image, and the values of FP signals were obtained separately by image analysis. The results showed the analytical performance of our system was comparable to that of conventional apparatus and which implies our system can be applicable to molecular interaction analysis. - Masatoshi Maeki, Saya Sato, Akihiko Ishida, Hirofumi Tani, Manabu Tokeshi 21st International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2017 1279 -1280 2020年 [査読有り][通常論文]
© 17CBMS-0001. This paper reports a bottom-up fabrication technique of amyloid nanostructures and its application to an enzyme immobilized microfluidic device. The process consists 3 steps: (1) immobilization of lysozymes, (2) denaturation and growth of amyloid fibrils, and (3) immobilization of enzymes on the amyloid fibrils. The growth of amyloid fibrils was able to control by the concentration of lysozyme solution and incubation time. We evaluated the performance of enzyme immobilized amyloid fibrils by hydrolysis reaction. As a results, synthetic peptides and proteins were effectively digested compared with conventional method. - Masatoshi Maeki, Niko Kimura, Kazuki Shimizu, Kento Yonezawa, Nobutaka Shimizu, Akihiko Ishida, Hirofumi Tani, Manabu Tokeshi Proc. Micro TAS 2019 1478 -1479 2019年10月 [査読有り][通常論文]
This paper reports a time-resolved small angle X-ray scattering (SAXS) for understanding lipid nanoparticles (LNPs) structure dynamics. The structure and its dynamics are the indispensable factors to ensure the activity and therapeutic effect of LNP-based nanomedicines. However, the structure dynamics of LNPs are not well understood because of the limitation of measurement methodology. To overcome the problem, we developed microfluidic-based SAXS measurement technique combined with a synchrotron X-ray source. We confirmed the LNPs decomposition process and LNPs aggregation process by pH change of the solution. - Ayano Nakamura, Osamu Wakao, Ken Satou, Mitsutoshi Aoyagi, Kazuhiko Nishimura, Chikaaki Mizokuchi, Ken Sumiyoshi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Koji Shigemura, Akihide Hibara, Manabu Tokeshi Proc. Micro TAS 2019 1393 -1394 2019年10月 [査読有り][通常論文]
This paper reports on a portable fluorescence polarization (FP) analyzer capable of on-site multisample immunoassay. The FP analyzer is small-size (W × D × H = 65 cm3), low cost (< $5,000), and high throughput (96 samples simultaneously). Using this analyzer, we demonstrated FP immunoassay (FPIA) for deoxynivalenol (DON), one of several mycotoxins that frequently infect wheat and other grains, spiked into wheat samples. The assay with the compact FP analyzer had sufficient accuracy to quantify DON in wheat in comparison with LC-MS/MS. Furthermore, multisample immunoassay was conducted by using a microdevice with 96 chambers. - Niko Kimura, Masatoshi Maeki, Yusuke Sato, Kosuke Sasaki, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Manabu Tokeshi Proc. Micro TAS 2019 368 -369 2019年10月 [査読有り][通常論文]
This paper describes development of a three-dimensional (3D) baffle mixer device for precise size control of various types of lipid nanoparticles (LNPs) with high encapsulation efficiency of short interfering RNAs (siRNAs). The 3D baffle mixer device achieved more precise size control of various LNPs than that of the conventional micromixer device. In addition, the 3D baffle mixer enabled effective capturing of siRNAs into LNPs without any assistance of electrostatic interaction between lipid molecules and siRNAs. The 3D baffle mixer device is expected to become one of the key platforms for production of novel lipid-based nucleic acid nanocarriers. - Reo Takeda, Masatoshi Maeki, Sho Ito, Go Ueno, Kunio Hirata, Akihiko Ishida, Hirofumi Tani, Masaki Yamamoto, Manabu Tokeshi Proc. Micro TAS 2019 191 -192 2019年10月 [査読有り][通常論文]
This paper reports development of a microfluidic-based high-throughput X-ray crystallography for protein-ligand complex structure analysis. Three-dimensional (3D) structure analysis of a protein-ligand complex requires complicated procedures. To improve the throughput performance, we developed a protein crystal array-based microfluidic device. The microfluidic device can effectively capture protein microcrystals into the microarray and continuously prepare protein-ligand complex samples. We determined lysozyme- p-toluenesulfonic acid complex and thaumatin-selenourea complex structures by serial on-chip X-ray diffraction measurement at room temperature. - Keine Nishiyama, Toshihiro Kasama, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Yoshinobu Baba, Manabu Tokeshi Proc. Micro TAS 2019 689 -690 2019年10月 [査読有り][通常論文]
This paper reports a novel method of signal amplification based on the accumulation of enzymatic fluorescent products at a wall-like structure (immuno-wall) in a microchannel for sensitive immunoassay. We found the function of an immuno-wall as a media for the enrichment of fluorescence molecules. We combined this function with the amplification of the fluorescence signal by an enzymatic reaction to produce a synergistic effect. The performance of the device was evaluated with human C-reactive protein (CRP) as a model target. The limit of detection of CRP was 2.5 pg/mL. This value was approximately 3 orders of magnitude lower than that obtained with a fluorescent dye-labeled antibody (1.7 ng/mL). - 西山 慶音, 木村 笑, 真栄城 正寿, 渡慶次 学 薬剤学: 生命とくすり 79 (3) 124 -129 2019年05月
- 西山慶音, 木村笑, 真栄城正寿, 渡慶次学 薬剤学(Web) 79 (3) 2019年
- 真栄城正寿 旭硝子財団研究助成成果発表会 2019 2019年
- 真栄城正寿, 真栄城正寿, 木村笑, 清水一樹, 石田晃彦, 谷博文, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 40th 2019年
- 木村笑, 真栄城正寿, 真栄城正寿, 石田明彦, 谷博文, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 40th 2019年
- 西山慶音, 武田洋平, 真栄城正寿, 石田晃彦, 谷博文, 重村幸治, 火原彰秀, 小川晴子, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 40th 2019年
- 真栄城正寿 旭硝子財団助成研究成果報告(Web) 2019 2019年
- 竹田怜央, 真栄城正寿, 真栄城正寿, 伊藤翔, 伊藤翔, 上野剛, 平田邦夫, 石田晃彦, 谷博文, 山本雅貴, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 39th 2019年
- 木村笑, 真栄城正寿, 岡部奈々, 佐藤悠介, 石田晃彦, 谷博文, 原島秀吉, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 39th 2019年
- 清田雄平, 真栄城正寿, 渡慶次学, 宮崎真佐也, 宮崎真佐也 化学とマイクロ・ナノシステム学会研究会講演要旨集 39th 2019年
- 真栄城正寿, 木村笑, 石田晃彦, 谷博文, 渡慶次学 日本分析化学会年会講演要旨集(Web) 68th 134 -134 2019年
- 石田晃彦, 西村卓馬, 真栄城正寿, 谷博文, 渡慶次学 日本分析化学会年会講演要旨集(Web) 68th 2019年
- Wataru Iwasaki, Kenichi Yananaka, Daisuke Sugiyama, Yuki Teshima, Masatoshi Maeki, Maria Portia, P. Briones-Nagata, Kenichi Yamashita, Masashi Takahashi, Masaya Miyazaki Proc. Micro TAS 2018 3 1727 -1728 2018年11月 [査読有り][通常論文]
We fabricated a microfluidic device for separation of bovine oocytes based on its quality to improve the conception rate of in vitro fertilization by using good quality oocytes. The microfluidic device separates oocytes based on sedimentation rate differences in a sucrose buffer, depending on the oocyte quality. We performed IVF after the microfluidic separation of oocytes. The developmental rate to blastocyst of oocytes collected from the lower outlet was significantly higher than those collected from the upper outlet. These findings indicate that our microfluidic device could be applied to contribute to the improvement of the in vitro embryo production system. - Masatoshi Maeki, Shohei Yamazaki, Akihiko Ishida, Hirofumi Tani, Manabu Tokeshi Proc. Micro TAS 2018 4 2192 -2193 2018年11月 [査読有り][通常論文]
This paper reports a microscopic real-time measurement of protein crystal growth in microfluidic devices to understand the effect of micro space on the protein crystal growth. Lysozyme crystallization behavior was observed using an optical microscope and we found that the orientation percentage of the (1 1 0) phase was depending on the depth of the crystallization chambers. The concentration profile and growth rate of lysozyme crystal in the microfluidic device was determined by in situ Raman spectroscopy and laser confocal microscopy-combined with differential interference contrast microscopy (LCM-DIM). The crystal growth rate in 10 and 20 μm depth crystallization chamber was 10 times slower than that of the other devices. - Microfluidic stepwise and rapid ethanol dilution for precise size control of lipid nanoparticlesNiko Kimura, Masatoshi Maeki, Nana Okabe, Yusuke Sato, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Manabu Tokeshi Proc. Micro TAS 2018 1404 -1405 2018年11月 [査読有り][通常論文]
- 龍美月, 龍美月, KURNIAWAN Y.S, SATHULURI R.R, 岩崎渉, 森貞真太郎, 川喜田英孝, 大渡啓介, 真栄城正寿, 宮崎真佐也, JUMINA 化学とマイクロ・ナノシステム学会研究会講演要旨集 38th 41 2018年10月30日 [査読無し][通常論文]
- 岩崎渉, 山中賢一, 永田マリアポーシャ, 真栄城正寿, 山下健一, 高橋昌志, 宮崎真佐也, 宮崎真佐也 化学とマイクロ・ナノシステム学会研究会講演要旨集 38th 83 2018年10月30日 [査読無し][通常論文]
- 血中ATPと乳酸を指標とする重症度診断のための電気化学酵素センサーの開発水上 良平, 真栄城 正寿, 石田 晃彦, 谷 博文, 渡慶次 学 日本分析化学会講演要旨集 67年会 287 -287 2018年08月
- ナノピラーデバイスを用いたDNAのサイズ分離と無標識検出阿尻 大雅, 安井 隆雄, 笠 晴也, 真栄城 正寿, 石田 晃彦, 谷 博文, 西井 準治, 馬場 嘉信, 渡慶次 学 日本分析化学会講演要旨集 67年会 125 -125 2018年08月 [査読無し][通常論文]
- 微小化脂質ナノ粒子によるアジュバントのリンパ節送達中村 孝司, 河合 美典, 佐藤 悠介, 真栄城 正寿, 渡慶次 学, 原島 秀吉 日本薬剤学会年会講演要旨集 33年会 193 -193 2018年05月
- がん組織における浸潤性向上を目指した極小脂質ナノ粒子の開発岡部 奈々, 佐藤 悠介, 真栄城 正寿, 渡慶次 学, 原島 秀吉 日本薬学会年会要旨集 138年会 (4) 78 -78 2018年03月
- 中股征哉, 笠間敏博, 笠間敏博, 長谷哲成, 與語直之, 與語直之, 小沢直也, 真栄城正寿, 石田晃彦, 佐藤光夫, 加地範匡, 谷博文, 長谷川好規, 馬場嘉信, 馬場嘉信, 渡慶次学 化学系学協会北海道支部冬季研究発表会(Web) 2018 2018年
- 木村笑, 真栄城正寿, 岡部奈々, 佐藤悠介, 石田晃彦, 谷博文, 原島秀吉, 渡慶次学, 渡慶次学, 渡慶次学, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 37th 2018年
- 木村笑, 真栄城正寿, 渡慶次学 ケミカルエンジニヤリング 63 (6) 2018年
- Niko Kimura, Masatoshi Maeki, Nana Okabe, Yusuke Sato, Akihiko Ishida, Hirofumi Tani, Hideyoshi Harashima, Manabu Tokeshi 22nd International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2018 3 1404 -1405 2018年This paper reports a methodology for precise controlling the lipid nanoparticle (LNP) size by stepwise and rapid ethanol dilution using an integrated microfluidic device with baffle mixers. The integrated microfluidic device coupling the LNP synthesis and the post-treatment regions had better size controllability of LNPs than the conventional preparation methods. Additionally, 30 nm-sized siRNA-loaded LNPs prepared by the post-treatment process using the integrated microfluidic device showed great gene-silencing activity and specific intrahepatic biodistribution. The stepwise and rapid ethanol dilution methodology using the integrated microfluidic device provides LNPs with homogeneous size distribution for improving the efficacy of nanomedicines.
- 真栄城 正寿, 宮崎 真佐也, 渡慶次 学 ぶんせき (516) 575 -580 2017年12月
- 尿中シュウ酸分析のための単一くし形電極を組み込んだ液体クロマトグラフィーチップの開発藤井 大地, 真栄城 正寿, 石田 晃彦, 谷 博文, 渡慶次 学 日本分析化学会講演要旨集 66年会 24 -24 2017年08月
- マイクロ流体デバイスを用いた化学発光イムノアッセイの高感度化菊地 優仁, 真栄城 正寿, 石田 晃彦, 谷 博文, 渡慶次 学 日本分析化学会講演要旨集 66年会 52 -52 2017年08月
- 血中ATPと乳酸測定のための電気化学センサーの開発水上 良平, 西山 慶音, 真栄城 正寿, 石田 晃彦, 谷 博文, 渡慶次 学 日本分析化学会講演要旨集 66年会 134 -134 2017年08月
- リンパ節内樹状細胞を標的とした極小ナノキャリアシステムの開発河合 美典, 中村 孝司, 佐藤 悠介, 真栄城 正寿, 原島 秀吉 日本DDS学会学術集会プログラム予稿集 33回 175 -175 2017年06月
- 阿尻大雅, 安井隆雄, 安井隆雄, 笠晴也, 真栄城正寿, 石田晃彦, 谷博文, 西井準治, 馬場嘉信, 馬場嘉信, 渡慶次学, 渡慶次学 キャピラリー電気泳動シンポジウム講演要旨集 37th 2017年
- 木村笑, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 35th 2017年
- 真栄城正寿, 木村笑, 佐藤悠介, 石田晃彦, 谷博文, 原島秀吉, 渡慶次学 化学工学会秋季大会研究発表講演要旨集(CD-ROM) 49th 2017年
- 木村笑, 真栄城正寿, 石田晃彦, 谷博文, 渡慶次学 化学とマイクロ・ナノシステム 16 (2) 2017年
- Saeed Mohammadi, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Manabu Tokeshi Proceedings of MicroTAS 2016 970 -971 2016年10月 [査読有り][通常論文]
This paper presents a novel washing technique for microfluidic paper-based analytical devices (μPADs) to remove unbound antigen or antibodies from paper substrates in multistep assays and achieve higher sensitivity and reproducibility relying on spontaneous capillary force of the paper. - Osamu Wakao, Masatoshi Maeki, Akihiko Ishida, Hirofumi Tani, Akihide Hibara, Manabu Tokeshi Proceedings of MicroTAS 2016 1400 -1401 2016年10月 [査読有り][通常論文]
We report a new high-throughput homogeneous assay format using a microchamber array towards molecular interactions analysis. The assay format is based on the fluorescence polarization (FP) detection using liquid-crystal display (LCD) that can switches a direction of FP by changing its images. In this work, we demonstrate a multiple sample FP immunoassay (FPIA) of prostaglandin E2 in a microchamber array to simultaneously analyze 25 samples. FP signals were imaged simultaneously and their values were acquired separately. This result showed our format with high-throughput had a measurement performance comparable to that of a conventional apparatus designed to single analysis. - マイクロ分析チップの新たな可能性渡慶次学, 真栄城正寿 JPCA NEWS 576 8 -13 2016年09月 [査読無し][招待有り]
- 血中リチウム濃度測定のためのペーパーデバイスの開発小松 雄士, 真栄城 正寿, 石田 晃彦, 谷 博文, 渡慶次 学 日本分析化学会講演要旨集 65年会 163 -163 2016年08月
- がん診断のためのエクソソーム分析法の開発阿尻 大雅, 安井 隆雄, 真栄城 正寿, 石田 晃彦, 谷 博文, 馬場 嘉信, 渡慶次 学 日本分析化学会講演要旨集 65年会 165 -165 2016年08月 [査読無し][通常論文]
- マイクロチップを用いた局在型表面プラズモン共鳴センサー真栄城正寿 ぶんせき 2016年04月 [査読無し][招待有り]
- 阿尻大雅, 安井隆雄, 安井隆雄, 石田晃彦, 谷博文, 真栄城正寿, 馬場嘉信, 馬場嘉信, 渡慶次学, 渡慶次学 化学系学協会北海道支部冬季研究発表会講演要旨集(CD-ROM) 2016 2016年
- Y. Fujishima, M. Maeki, Y. Sato, T. Yasui, A. Ishida, H. Tani, Y. Baba, H. Harashima, M. Tokeshi 20th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2016 1412 -1413 2016年 [査読有り][通常論文]
This paper describes lipid nanoparticles (LNPs) formation behavior in microfluidic devices equipped with the staggered herringbone micromixers (SHM) in order to control the LNPs size precisely. Three types of microfluidic devices with different heights of mixer structures were fabricated to examine the effect of mixer structure on the LNPs formation behavior. We found the height of the grooved structures, the lipid concentration, and the ethanol concentration were significant factors for controlling LNPs size and its distribution. - 液晶ディスプレイを利用した蛍光偏光イメージング若尾摂, 真栄城正寿, 火原彰秀, 渡慶次学 ケミカルエンジニアリング 6 12 -17 2016年01月 [査読無し][招待有り]
- マイクロ化学チップの最新動向：紙チップとタンパク質結晶構造解析チップ真栄城正寿, 渡慶次学 クリーン・テクノロジー 25 (11) 1 -4 2015年11月 [査読無し][招待有り]
- 若尾摂, 真栄城正寿, 石田晃彦, 谷博文, 火原彰秀, 渡慶次学 Proceedings of MicroTAS 2015 1816 -1818 2015年10月 [査読有り][通常論文]
This paper reports a unique fluorescence polarization (FP) imaging system with a microchip applicable to multisample simultaneous FP immunoassay. The measurement principle of the system has already been reported [1]. In this work, we present a FP imaging immunoassay for multisample of physiologically active substances (prostaglandin E2, PGE2). FP signals of all samples in the captured by an image sensor were imaged simultaneously, and their values were acquired separately from the image analysis. The analytical performance of this assay system was comparable to that of conventional apparatus. The result is the first demonstration of the multisample FP imaging immunoassay. - 紙を利用した分析・診断チップ真栄城正寿, 渡慶次学 紙パルプ技術タイムス 58 37 -42 2015年08月 [査読無し][招待有り]
- M. Maeki, T. Saito, Y. Node, Y. Sato, T. Yasui, N. Kaji, A. Ishida, H. Tani, Y. Baba, H. Harashima, M. Tokeshi MicroTAS 2015 - 19th International Conference on Miniaturized Systems for Chemistry and Life Sciences 838 -840 2015年 [査読有り][通常論文]
© 15CBMS-0001. This paper described a simple preparation method for small-size and monodispersed lipid nanoparticles (LNPs) by using microfluidic devices. The fundamental role and importance of chaotic micromixer in the microfluidic device was demonstrated. The suitable cycle number of chaotic micromixer was confirmed for precise controlling LNPs size with narrow distribution under the any flow rate conditions. In addition, LNPs containing siRNA was synthesized for evaluation of penetration efficiency via in vivo experiment. The PEGylated LNPs containing siRNA with a diameter of 30 nm could penetrate to the mouse parenchymal liver cells rather than the LNPs with a diameter of 50 nm. - 手島裕貴, 杉山大輔, 真栄城正寿, 岩崎渉, 山下健一, 山中賢一, 高橋昌志, 宮崎真佐也 化学とマイクロ・ナノシステム学会研究会講演要旨集 30th 41 2014年10月02日 [査読無し][通常論文]
- 真栄城正寿, Ashtamurthy S. Pawate, 渡邉啓一, 渡慶次学, Paul J. A. Kenis, 宮崎真佐也 Proceedings of MicroTAS 2014 1083 -1085 2014年10月 [査読有り][通常論文]
We demonstrate a novel method for controlling morphology and aggregation of protein crystals by focusing on the depth of microchannel. The microfluidic chip with normally closed valves was fabricated for crystallization experiments and in-situ X-ray analysis. Crystal habit of protein was dramatically changed by depth of crystallization chamber. We found the potential of microfluidic chip for controlling crystal habit as well as aggregation of protein crystals. - Application of Microreactor System in Solvent Extraction of Metal ion With Calixarene Derivatives真栄城正寿, Jee Young Kim, 宮崎真佐也, 大渡啓介 Proceedings of International Solvent Extraction Conference 2014 711 -715 2014年09月 [査読有り][通常論文]
- 齋藤竜亮, 真栄城正寿, 安井隆雄, 安井隆雄, 石田晃彦, 谷博文, 馬場嘉信, 馬場嘉信, 渡慶次学, 渡慶次学 化学とマイクロ・ナノシステム学会研究会講演要旨集 30th 2014年
- マイクロ流体技術のタンパク質化学への応用真栄城正寿 化学とマイクロ・ナノシステム研究会誌 12 19 -22 2013年10月 [査読無し][招待有り]
- A Method for Generating Single Protein Crystal by Using Microfluidic Device真栄城正寿, 手島裕貴, 吉塚紗央里, 山口浩, 山下健一, 宮崎真佐也 Peptide Science 2012 387 -390 2013年02月 [査読有り][通常論文]
- Effective solvent extraction of metal ions with calixarene derivatives by using multiphase parallel flow真栄城正寿, 畑中雄太, 宮崎真佐也, 大渡啓介 Proceedings of Microfluidics 2012 (63) 1 -4 2012年12月 [査読有り][通常論文]
- A method for controlling nucleation profile using droplet based microfluidics that focus on the internal fluid dynamics真栄城正寿, 手島裕貴, 吉塚紗央里, 山口浩, 山下健一, 宮崎真佐也 Proceedings of Microfluidics 2012 (65) 1 -4 2012年12月 [査読有り][通常論文]
- 真栄城正寿, 手島裕貴, 吉塚紗央里, 山口浩, 山下健一, 宮崎真佐也 Proceedings of MicroTAS 2012 1219 -1221 2012年10月 [査読有り][通常論文]
This paper reports a method for generating single crystals by using droplet based microfluidics. We studied theoretical background, and estimated the droplet size for obtaining only one ciystal within each droplet. We also investigated crystallization behavior of four model proteins to confirm the effect of protein molecular diffusion on crystallization. A single ciystal was obtained within a microdroplet which was smaller than the critical size. We consider that single crystallization or decoupling protein nucleation and crystal growth can be easily achieved by controlling droplet size. - R6. Control of protein crystallization within nanodroplets for X-ray crystal structure Analysis真栄城 正寿 化学とマイクロ・ナノシステム研究会誌 10 24 -25 2011年10月 [査読無し][招待有り]
- Control of protein crystallization in nanodroplets for X-ray crystal structure analysis真栄城正寿, 山口浩, 仁田原智, 河本正秀, 山下健一, 宮崎真佐也, 前田英明 Peptide Science 2011 397 -400 2011年02月 [査読有り][通常論文]
特許
- 特願2023-027872:ミトコンドリアゲノム編集用脂質ナノ粒子 2023年02月27日山田勇磨, 原島秀吉, 佐藤悠介, 石塚宣, 野呂田楓, 渡慶次学, 真栄城正寿 北海道大学
- 特願PCT/JP2023/005885:脂質粒子含有液、その製造方法及びキット 2023年02月20日真栄城正寿, 渡慶次学, 丹羽彩由花, 米田明弘, 岡田悠斗, 杉浦魁星, 村野健作 北海道大学
- 特願PCT/JP2023/004007:流路構造体およびこれを用いた自己組織化物質粒子の製造方法 2023年02月07日真栄城正寿, 渡慶次学 北海道大学
- 特願2022-158025:核酸複合体組成物、遺伝子導入用脂質粒子及びそれを用いた遺伝子導入方法 2022年09月30日真栄城正寿, 渡慶次学, 宇野秀哉, 原島秀吉, 佐藤悠介 北海道大学
- 特願2022-025776:脂質粒子含有液及びその製造方法 2022年02月24日真栄城正寿, 渡慶次学, 岡田悠斗, 村野健作
- 特願2022-025530:脂質粒子含有液及びその製造方法 2022年02月24日真栄城正寿, 渡慶次学, 丹羽彩由花, 米田明弘 北海道大学
- 特願2021-193746:マイクロ流路デバイスを用いた結晶製造方法及び装置 2021年11月30日田中伊知朗, 長谷川智紀, 新村信雄, 齋藤洋也, 山田貢, 石田卓也, 吉崎泉, 皆川由貴, 伊藤剛士, 真栄城正寿 茨城大学
- 特許7014469号:3次元流路構造体およびこれを用いたナノ粒子の製造法真栄城正寿, 渡慶次学, 木村笑, 佐藤悠介, 原島秀吉
- 特願2019-101203:脂質ナノ粒子 2019年05月30日佐藤悠介, 原島秀吉, 渡慶次学, 真栄城正寿
- 特願2019-070124:リポソーム様ナノカプセル及びその製造方法 2019年04月01日山田勇磨, 原島秀吉, 日比野光恵, 佐藤悠介, 渡慶次学, 真栄城正寿
- 特許7014469号:粒子含有水溶液の製造方法真栄城正寿, 渡慶次学, 木村笑, 佐藤悠介, 原島秀吉
- WO2018-190423:流路構造体およびこれを用いた脂質粒子ないしミセル形成方法 2018年10月18日渡慶次 学, 真栄城 正寿, 佐藤 悠介, 原島 秀吉 国立大学法人北海道大学 202003014356594694
- 特許6942376号:流路構造体およびこれを用いた脂質粒子形成方法渡慶次学, 真栄城正寿, 佐藤悠介, 原島秀吉
- 山下 健一, 宮崎 真佐也, 中村 浩之, 前田 英明, 山口 浩, 真栄城 正寿 独立行政法人産業技術総合研究所 201303044408528360
受賞
- 2023年05月 船井情報科学振興財団 令和4年度 船井学術賞
創薬研究を加速するマイクロ流体デバイス開発に関する研究受賞者: 真栄城正寿 - 2023年02月 北海道 令和4年度北海道科学技術奨励賞
マイクロ流体デバイスを用いた脂質ナノ粒子製造技術の開発とナノ医薬品開発への展開受賞者: 真栄城正寿 - 2021年02月 日本化学会北海道支部 ２０２０年度 日本化学会北海道支部奨励賞
機能集積化マイクロ化学デバイスの開発と医薬分野 への展開受賞者: 真栄城正寿 - 2018年07月 日本分析化学会 Most Cited Paper 2017
Microfluidic Approaches for Protein Crystal Structure Analysis受賞者: 真栄城 正寿 - 2017年04月 公益財団法人 船井情報科学振興財団 船井研究奨励賞
マイクロデバイスを用いたタンパク質立体構造解析法に関する研究受賞者: 真栄城 正寿 - 2017年01月 日本分析化学会北海道支部 2016年度北海道分析化学会奨励賞
マイクロデバイスを用いたタンパク質の立体構造解析法の開発受賞者: 真栄城 正寿 - 2016年09月 公益社団法人 日本分析化学会 2016年度日本分析化学会奨励賞
機能集積化マイクロ分析デバイスの開発と医薬学分野への応用受賞者: 真栄城 正寿 - 2016年03月 一般社団法人 化学とマイクロ・ナノシステム学会 平成27年度化学とマイクロ・ナノシステム学会若手優秀賞
マイクロ流体制御によるタンパク質立体構造解析システムの開発受賞者: 真栄城 正寿 - 2016年01月 Analytical Sciences Hot Article Award Analytical Sciences
"Microfluidic Approaches for Protein Crystal Structure Analysis"受賞者: Masatoshi Maeki;Hiroshi Yamaguchi;Manabu Tokeshi;Masaya Miyazaki - 2015年11月 一般財団法人 エヌエフ基金 第4回研究開発奨励賞
受賞者: 真栄城 正寿 - 2014年06月 日本素材物性学会 山崎賞
受賞者: 真栄城 正寿
共同研究・競争的資金等の研究課題
- 日本学術振興会：科学研究費助成事業研究期間 : 2023年04月 -2026年03月代表者 : 山田 勇磨, 真栄城 正寿, 武田 充人, 佐々木 大輔, 日比野 光恵
- 日本学術振興会：科学研究費助成事業 国際共同研究加速基金(国際共同研究強化(B))研究期間 : 2019年10月 -2023年03月代表者 : 加地 範匡, 渡慶次 学, 真栄城 正寿本国際共同研究では、日本・オランダ・シンガポールの各研究グループが独自に有するマイクロ・ナノテクノロジー、デバイス技術、エクソソーム分離・解析、エクソソーム高機能化、単一細胞アッセイ、細胞スフェロイドアッセイの各要素技術を結集して融合することで、再生医療やがん免疫療法に応用可能な高機能ハイブリッドエクソソームの創製を目的とする。本研究期間中、世界屈指の超微細加工技術とそれを可能とする施設を有するトウェンテ大学、基礎研究から臨床研究まで包括的に研究を行う体制が整っているシンガポール国立大学に若手研究者が3ヶ月以上滞在し、超微細加工技術から細胞スフェロイドアッセイ技術までを習得することで、エクソソームの選択的捕捉・分離・解析・高機能化から単一細胞・細胞スフェロイドアッセイが可能な統合型デバイスの研究開発をおこなうことを目指した。 本研究の当初計画では、参画研究者がトウェンテ大学に長期滞在してデバイス作製技術の習得並びに作製と評価を行う予定であったが、昨年度に引き続いて今年度もコロナ禍のために海外渡航が叶わず、また国内での移動も多くの制限が課されていたため、オンラインディスカッションと各研究室で実施可能な基礎検討を中心に研究を行った。具体的には、外部バルス電界によるエクソソームへの外来物質導入やデバイスを用いた精製・評価法の検討を行い、最適な粒子濃度・電場強度を見出すとともに、長期保存における安定性についても評価を行った。その結果、牛乳由来エクソソームに関しては、粒子濃度が高く、電場強度が強いほど、外来物質の導入効率が高まることを明らかとした。また3ヶ月間の凍結保存においては、エクソソームの粒径などの正常に影響がないことも分かった。
- 秘密保持のため非公開C社：共同研究契約研究期間 : 2020年10月 -2023年03月
- 人工エクソソームによる長鎖DNAの細胞導入法の開発科学技術振興機構（JST）：さきがけ研究期間 : 2019年10月 -2023年03月
- 人工エクソソーム医薬品製造技術の開発と事業化検証JST：社会還元加速プログラム(SCORE) 大学推進型(拠点都市環境整備型) 起業活動支援プログラム研究期間 : 2021年09月 -2022年03月
- 細胞内量子イメージングのための蛍光ナノダイヤモンド搭載脂質ナノ粒子の開発池谷科学技術振興財団：2021年度 単年度研究助成研究期間 : 2021年04月 -2022年03月
- 秘密保持のため非公開B社：学術コンサルティング研究期間 : 2020年07月 -2022年03月
- 日本学術振興会：科学研究費助成事業 挑戦的研究(萌芽)研究期間 : 2019年06月 -2021年03月代表者 : 杉本 宏, 真栄城 正寿シトクロムP450ファミリーのタンパク質が触媒するモノオキシゲナーゼ反応は、逐次的に電子・酸素・プロトンの供給が必要である。このような多段階の複雑な反応を結晶相で制御するためのデバイスを作成し、X線自由電子レーザー（XFEL）を用いたシリアルX線結晶回折データ測定のために有効なツールとなることを示した。光反応サイクルをもたない一般のタンパク質でも時間分解構造解析の対象にして動的な分子メカニズムを解明する道を拓くものである。
- 日本学術振興会：科学研究費助成事業 若手研究研究期間 : 2019年04月 -2021年03月代表者 : 真栄城 正寿タンパク質とリガンド複合体の立体構造情報は、創薬において不可欠である。タンパク質の立体構造は、おもにX線結晶構造解析で決定されている。特に、タンパク質・リガンド複合体の構造解析においては、リガンドの結合サイトまで決定できる点は、ほかの測定法にはない優れた特徴である。一方で、従来のX線結晶構造解析の測定効率はそれほど高くなく、また、タンパク質・リガンドの複合体構造解析には、煩雑な前処理が必要なため、測定スループットの改善が望まれていた。そこで本研究では、タンパク質・リガンド複合体の構造解析を高速化するためのマイクロデバイス、および、新規測定法の開発に取り組んだ。
- 秘密保持のため非公開A社：学術コンサルティング研究期間 : 2019年04月 -2021年03月
- PLGAナノ粒子の精密制御とDDSへの応用ホソカワ粉体工学振興財団：研究助成研究期間 : 2019年04月 -2020年03月代表者 : 真栄城 正寿
- マイクロ流体デバイスを用いた固定ターゲットタンパク質構造解析法の開発島津科学技術振興財団：2018年度研究開発助成金研究期間 : 2019年04月 -2020年03月代表者 : 真栄城 正寿
- マイクロ・ナノデバイスによるエクソソームの包括的情報解析とガン診断への応用中谷医工計測技術振興財団：奨励研究研究期間 : 2019年04月 -2020年03月代表者 : 真栄城 正寿
- マイクロデバイスを用いたコンビナトリアル合成システムの開発とDDSナノ粒子設計への応用JKA 研究補助（機械振興）：個別研究研究期間 : 2019年04月 -2020年03月代表者 : 真栄城 正寿
- 日本学術振興会：科学研究費助成事業 若手研究(B)研究期間 : 2017年04月 -2019年03月代表者 : 真栄城 正寿本研究課題では、マイクロデバイスにタンパク質の結晶を集積化（アレイ化）し、オンチップでX線結晶構造解析を行い、タンパク質の立体構造を決定する手法の開発に取り組んだ。マイクロデバイスは、一般的なソフトリソグラフィーによってPDMS流路を作製し、シクロオレフィンポリマー薄膜と接着することで作製した。デバイスの厚みは、220 um～500 umとした。タンパク質の結晶をアレイ化するために、①昨年度まで取り組んでいたオンチップで結晶化を行いマイクロウェルにアレイ化する方法、②オフチップで結晶化を行い、調製した結晶懸濁液をデバイスに送液して、マイクロウェルにアレイ化する方法を確立した。 また、オンチップX線結晶構造解析の方法として、100Kにおいて凍結した1個の単結晶から回折データを取得する従来の方法から、室温下において複数の単結晶から回折データを取得し、それぞれの回折データをマージして立体構造を決定する方法を確立した。モデルタンパク質として、リゾチームのオンチップX線結晶構造解析をフォトンファクトリー、および、SPring-8で行なった。その結果、室温下においても1.5オングストローム程度の分解能で構造決定可能であった。従来の方法では、放射線損傷の影響を避けるために100Kの超低温下で測定を行なっていたが、室温での測定が可能となったため、より生理条件に近い状態での立体構造解析が可能となった。今後は、様々な種類のタンパク質の構造解析へ応用し、タンパク質-リガンド複合体の解析などへの応用を目指す。
- 化合物スクリーニングのハイスループット化を目指したマイクロ流路デバイス開発日本医療研究開発機構（AMED）：創薬等ライフサイエンス研究支援基盤事業 創薬等ライフサイエンス研究のための相関構造解析プラットフォームによる支援と高度化研究期間 : 2018年09月 -2019年03月代表者 : 山本 雅貴
- 時間分解X線溶液散乱による脂質ナノ粒子の形成メカニズムの解明科学技術振興機構（JST）：科学技術人材育成費補助事業 ナノテクキャリアアップアライアンス N.R.P.研究期間 : 2018年04月 -2019年03月代表者 : 真栄城 正寿
- マイクロアレイデバイスによるタンパク質の立体構造解析法の開発旭硝子財団：旭硝子財団研究助成金研究期間 : 2017年04月 -2019年03月代表者 : 真栄城 正寿
- タンパク質の微結晶アレイによる構造解析法の開発日本学術振興会（JSPS）：科学研究費補助金（若手研究B）研究期間 : 2017年04月 -2019年03月代表者 : 真栄城 正寿
- 3 次元アミロイド構造体を利用した免疫測定チップの開発豊田理化学研究所：豊田理研スカラー研究期間 : 2016年04月 -2017年03月代表者 : 真栄城 正寿
- 日本学術振興会：科学研究費助成事業 特別研究員奨励費研究期間 : 2015年04月 -2016年03月代表者 : 真栄城 正寿今年度は、マイクロ流体技術を用いた結晶化制御方法の確立に取り組んだ。タンパク質結晶化は、これまでは熟練者の勘や経験に大きく依存していた。結晶化制御は経験則に基づくことが多く、系内で複数の単結晶が合体や密集すると構造解析が困難になる。そこで、マイクロ流体制御技術と種結晶法を組み合わせたタンパク質結晶化制御方法の確立を試みた。まず、共同研究者から提供を受けた南極産好冷細菌由来のグルコキナーゼ（PsGK）の結晶化制御を行った。PsGKは、従来の結晶化方法（ハンギングドロップ蒸気拡散法）では、結晶同士が集積して良質な単結晶を作製することが困難であった。しかしながら、結晶化空間を精密に制御したマイクロ流体デバイスを用いることで、結晶化の制御が可能であった。また、結晶化空間のサイズ（深さ）によって、結晶化挙動が大きく変化することが明らかになった。具体的には、深さが50μmの結晶化空間ではロッド状の結晶が析出したが、深さが10μmの結晶化空間ではプレート状の結晶が析出した。この現象の普遍性を確認するために、リゾチーム、およびNADPH-シトクロムP450還元酵素-ヘムオキシゲナーゼ（CPR-HO）複合体の結晶化挙動の解析と制御に取り組んだ。CPR-HO複合体の結晶も従来の結晶化方法（ハンギングドロップ蒸気拡散法）では、結晶同士の集積が確認された。一方で、マイクロ流体デバイスでは、1個の単結晶のみを析出させることができた。
- 日本学術振興会：科学研究費助成事業 特別研究員奨励費研究期間 : 2013年04月 -2015年03月代表者 : 真栄城 正寿今年度は、基板上に形成させたテンプレートによるタンパク質結晶の核形成促進を目的として、昨年度設計した試作型デバイスを用いて、脂質二重膜をテンプレートにしたタンパク質の結晶化に着手した。さらに、その結果を基にしてマイクロ流体デバイスへの応用を試みた。 試作型デバイスは、金薄膜を蒸着したガラス基板上にリソグラフィー技術によってSU-8製のマイクロウェルを作製した。マイクロウェル上に脂質二重膜を形成させ、その上にHisタグ付きタンパク質を固定化してテンプレートを作製した。結晶化に最適なテンプレートを作製するために、溶液濃度や脂質二重膜の条件、固定化時間などを検討した。Hisタグ付きGFPをモデルタンパク質として結晶化実験を行った。脂質の種類、脂質の混合比について検討を行った結果、Hisタグ付きGFPを固定するための脂質濃度が高くなるにつれて、GFPの結晶が析出しにくくなることが分かった。一方で、脂質の混合比を調整して、hisタグ付きタンパク質の濃度を低下させると、液滴中に多数の結晶の析出が観測された。これらの結果から、テンプレートであるHisタグ付きタンパク質の固定化密度が結晶化挙動に影響を与えていることが示唆された。 次に、本年度の目標であるマイクロ流体デバイスへの応用を行った。マイクロデバイスでは、1条件あたりに必要な結晶化溶液の体積は約30 nLであり、試作型と比較すると30~40分の1程度のサンプル量で結晶化が可能であった。また、単位体積あたりの結晶数を従来法や試作型デバイスと比較すると、析出した結晶数が劇的に増加することが明らかとなった。これらの結果から、マイクロ流体デバイスと脂質二重膜-Hisタグ付きタンパク質を用いた結晶化手法は、タンパク質の核形成を促進させる可能性が見出された。
教育活動情報
主要な担当授業
- 応用生物化学Ａ（生物計測化学）開講年度 : 2021年課程区分 : 修士課程開講学部 : 総合化学院キーワード : 分子認識，酵素反応，免疫反応，生体分子間相互作用，生物計測化学，マイクロ分析・診断デバイス
- 応用化学学生実験Ⅰ開講年度 : 2021年課程区分 : 学士課程開講学部 : 工学部キーワード : 実験技術、安全、酸化還元滴定、キレート滴定、酸塩基平衡、錯形成平衡、吸光光度法、クラジウス－クラペイロンの式、蒸発エンタルピー、電荷移動錯体、分子間相互作用、電極反応、計測制御、吸収・蛍光スペクトル、分子軌道論、反応速度、アレニウスの式
- 物質変換工学開講年度 : 2021年課程区分 : 学士課程開講学部 : 工学部キーワード : 有機合成，有機材料，化学プロセス，反応器設計，生体材料，高分子材料，分子機能，無機材料，複合材料，電子材料，光機能材料
- 化学英語開講年度 : 2021年課程区分 : 学士課程開講学部 : 工学部キーワード : 化学，英語，単語，表記法
- 化学Ⅰ開講年度 : 2021年課程区分 : 学士課程開講学部 : 全学教育キーワード : 原子の構造、原子軌道、化学結合、混成軌道、物質の三態、電解質溶液
大学運営
委員歴
- 2023年04月 - 現在 北海道大学大学院工学研究院 産学連携アドバイザリーチーム
- 2023年04月 - 現在 北海道大学大学院工学研究院 ヒトを対象とする研究倫理審査委員会委員
- 2022年04月 - 現在 MicroTAS Technical Program Committee
- 2022年04月 - 現在 日本分析化学会 北海道支部 会計担当幹事
- 2019年04月 - 現在 日本分析化学会 北海道支部 幹事（若手担当）
- 2019年04月 - 現在 化学とマイクロ・ナノシステム学会 化学とマイクロ・ナノシステム学会誌 編集委員
- 2018年04月 - 2020年09月 北海道大学 応用化学部門 広報委員（部門内委員）
- 2019年04月 - 2020年05月 第80回分析化学討論会 実行委員
- 2019年04月 - 2020年01月 化学系学協会北海道支部2020年 冬季研究発表会 実行委員
- 2017年04月 - 2019年03月 日本分析化学会 北海道支部 支部ニュース編集委員
- 2018年05月 - 2018年11月 化学とマイクロ・ナノシステム学会 第38回研究会 若手企画 副実行委員長
- 2018年05月 - 2018年11月 化学とマイクロ・ナノシステム学会 第38回研究会 実行委員（プログラム編集委員長）
- 2018年05月 - 2018年11月 第35回「センサ・マイクロマシンと応用システム」シンポジウム 実行委員
- 2018年03月 - 2018年06月 国際フォトテラノスティクス共同研究教育拠点（(独)日本学術振興会 研究拠点形成事業） 第2回若手国内シンポジウム オーガナイザー
- 2014年10月 化学とマイクロ・ナノシステム学会 第30回研究会 実行委員