GAO TIANLE

Faculty of Engineering Applied Chemistry Chemistry of Functional MoleculesSpecially Appointed Assistant Professor
Last Updated :2025/02/13

■Researcher basic information

Degree

  • Jun. 2024

Researchmap personal page

Researcher number

  • 61009990

■Career

Career

  • Jul. 2024 - Present
    北海道大学大学院工学研究院, 応用化学部門, 特任助教
  • Apr. 2024 - Jul. 2024
    Japan Society for the Promotion of Science, 特別研究員 (DC2)

Educational Background

  • Oct. 2021 - Jun. 2024, 北海道大学, 応用化学
  • Oct. 2019 - Sep. 2021, Hokkaido University, 応用化学, 博士前期課程
  • Oct. 2015 - Jun. 2019, Harbin Engineering University

■Research activity information

Papers

  • Toward Fully Controllable Monomers Sequence: Binary Organocatalyzed Polymerization from Epoxide/Aziridine/Cyclic Anhydride Monomer Mixture
    Tianle Gao, Xiaochao Xia, Tomohisa Watanabe, Chun-Yao Ke, Ryota Suzuki, Takuya Yamamoto, Feng Li, Takuya Isono, Toshifumi Satoh
    Journal of the American Chemical Society, American Chemical Society (ACS), 31 Jul. 2024, [Peer-reviewed]
    Scientific journal
  • Synthesis of Amino-Functionalized Polyester via Ring-Opening Alternating Copolymerization of Glycidylamines with Cyclic Anhydrides
    Ryota Suzuki, Tianle Gao, Ayaka Sumi, Takuya Yamamoto, Kenji Tajima, Feng Li, Takuya Isono, Toshifumi Satoh
    Polymer Chemistry, Royal Society of Chemistry (RSC), 2024
    English, Scientific journal, Amino-functionalized polyesters (APEs) are a remarkable class of polymeric materials with a wide range of applications, e.g. as antibacterial materials, gene delivery carriers, and biodegradable plastics. However, the current APE...
  • One-Step Synthesis of Poly(amide ester)-Based Block Copolymers with Defined Phase Separation Behavior
    Tianle Gao, Feng Li, Ryota Suzuki, Huan Li, Takuya Yamamoto, Xiaochao Xia, Takuya Isono, Toshifumi Satoh
    Macromolecules, 56, 20, 8333, 8343, 24 Oct. 2023
    Scientific journal, We developed a self-switchable, one-step polymerization system based on N-tosylaziridine (TAz)/cyclic anhydride ring-opening copolymerization (ROCOP), cyclic carbonate ring-opening polymerization (ROP), and epoxide/anhydride ROCOP. This system uses a phosphazene-based catalyst for the synthesis of chemical structurally diverse block copolymers. “Block-like” poly(amide ester)s were synthesized by combining two catalytic cycles of TAz/anhydride ROCOP. “Real” block poly(amide ester)-b-polycarbonate and poly(amide ester)-b-polyester were then synthesized by combining TAz/anhydride ROCOP with cyclic carbonate ROP and epoxide/anhydride ROCOP, respectively. Differential scanning calorimetry revealed two glass transition temperatures for the “real” block copolymers, and small-angle X-ray scattering measurements confirmed microphase separation, illustrating a significant difference in polarity between the two blocks of copolymers. These results confirm the precise control of the chemical structure and properties of each block on the synthesized copolymers. This method also enables the comprehensive and synchronous adjustment of the chemical structures of copolymer blocks, a challenge that has received much attention in the field of copolymer synthesis.
  • Sequential Polymerization from Complex Monomer Mixtures: Access to Multiblock Copolymers with Adjustable Sequence, Topology, and Gradient Strength
    Xiaochao Xia, Tianle Gao, Feng Li, Ryota Suzuki, Takuya Isono, Toshifumi Satoh
    Macromolecules, 56, 1, 92, 103, 10 Jan. 2023
    Scientific journal, Switchable polymerization shows considerable potential for simulating the molecular precision of natural biopolymers, such as nucleic acids or proteins, to synthesize highly sequence-controlled macromolecules but is mainly limited to three- and four-component systems. To expand the scope to systems with up to five components, we established a reactivity gradient among 12 monomers, including cyclic anhydrides, cyclic esters, and epoxides. Highly selective competitive anhydride/epoxide, self-switchable cyclic anhydride/epoxide/cyclic ester, and competitive cyclic ester/trimethylene carbonate copolymerizations were achieved using a simple alkyl metal carboxylate catalyst. Anhydrides gave access to gradient copolymers with reactivity ratios of 2 < r1 < 5, 0.7 > r2 > 0.3 giving medium-gradient copolymers and r1 > 400, r2 < 0.03 giving block copolymers. Further, the anhydride reactivity was predicted using 13C NMR chemical shifts. This comonomer library will allow more complex copolymer structures with adjustable sequence, topology, and gradient strength to be predicted and prepared.
  • One-step synthesis of sequence-controlled multiblock polymers with up to 11 segments from monomer mixture
    Xiaochao Xia, Ryota Suzuki, Tianle Gao, Takuya Isono, Toshifumi Satoh
    Nature Communications, 13, 1, Dec. 2022
    Scientific journal, Switchable polymerization holds considerable potential for the synthesis of highly sequence-controlled multiblock. To date, this method has been limited to three-component systems, which enables the straightforward synthesis of multiblock polymers with less than five blocks. Herein, we report a self-switchable polymerization enabled by simple alkali metal carboxylate catalysts that directly polymerize six-component mixtures into multiblock polymers consisting of up to 11 blocks. Without an external trigger, the catalyst polymerization spontaneously connects five catalytic cycles in an orderly manner, involving four anhydride/epoxide ring-opening copolymerizations and one L-lactide ring-opening polymerization, creating a one-step synthetic pathway. Following this autotandem catalysis, reasonable combinations of different catalytic cycles allow the direct preparation of diverse, sequence-controlled, multiblock copolymers even containing various hyperbranched architectures. This method shows considerable promise in the synthesis of sequentially and architecturally complex polymers, with high monomer sequence control that provides the potential for designing materials.
  • Polyether/Polythioether Synthesis via Ring-Opening Polymerization of Epoxides and Episulfides Catalyzed by Alkali Metal Carboxylates
    Tianle Gao, Xiaochao Xia, Kenji Tajima, Takuya Yamamoto, Takuya Isono, Toshifumi Satoh
    Macromolecules, 55, 21, 9373, 9383, 08 Nov. 2022
    Scientific journal, Alkali metal carboxylates were evaluated as simple and green catalysts for the ring-opening polymerization (ROP) of various epoxides (e.g., alkyl-substituted epoxides and glycidyl ethers) and episulfides (alkyl-substituted episulfides and thioglycidyl ethers). The thus-produced functional polyethers (end-functionalized polyethers, block copolyethers, polyether-polyester block copolymers, topologically unique polyethers, and isotactic-enriched polyethers) and polythioethers featured well-defined structures and controlled molecular weights (Mn,SEC= 1.0-32 kg mol-1). The most effective catalyst was identified as cesium pivalate, and the variation of carboxylate moieties and alkali metal cations enabled the tuning of acid/base characteristics and thus allowed one to control polymerization behavior and expand the scope of functional monomers and initiators. Kinetic analysis confirmed the controlled/living nature of the polymerization process, while mechanistic studies revealed that carboxylate moieties did not directly initiate the ring-opening of epoxide monomers via nucleophilic attack but rather activated the alcohol initiators/chain ends via H-bonding and thus rendered the corresponding OH groups sufficiently nucleophilic to attack the alkali metal cation-activated epoxides.
  • Multidimensional Control of Repeating Unit/Sequence/Topology for One-Step Synthesis of Block Polymers from Monomer Mixtures
    Xiaochao Xia, Tianle Gao, Feng Li, Ryota Suzuki, Takuya Isono, Toshifumi Satoh
    Journal of the American Chemical Society, 144, 39, 17905, 17915, 05 Oct. 2022
    Scientific journal, Synchronously and thoroughly adjusting the chemical structure difference between two blocks of the diblock copolymer is very useful for designing materials but difficult to achieve via self-switchable alternating copolymerization. Here, we report self-switchable alternating copolymerization from a mixture of two different cyclic anhydrides, epoxides, and oxetanes, where a simple alkali metal carboxylate catalyst switches between ring-opening alternating copolymerization (ROCOP) of cyclic anhydrides/epoxides and ROCOP of cyclic anhydrides/oxetanes, resulting in the formation of a perfect block tetrapolymer. By investigating the reactivity ratio of these comonomers, a reactivity gradient was established, enabling the precise synthesis of block copolymers with synchronous adjustment of each unit's chemical structure/sequence/topology. Consequently, a diblock tetrapolymer with two glass transition temperatures (Tg) can be easily produced by adjusting the difference in chemical structures between the two blocks.
  • Synthesis of hyperbranched polyesters via the ring-opening alternating copolymerisation of epoxides with a cyclic anhydride having a carboxyl group
    Ryota Suzuki, Xiaochao Xia, Tianle Gao, Takuya Yamamoto, Kenji Tajima, Takuya Isono, Toshifumi Satoh
    Polymer Chemistry, 13, 38, 5469, 5477, 26 Aug. 2022
    Scientific journal, Hyperbranched polyesters (HBPEs) are well-known interesting materials used in many fields. However, the known synthetic approaches for HBPEs lack versatility. Herein, we report a novel synthetic approach for an HBPE via ring-opening alternating copolymerisation (ROAC) using epoxides and trimellitic anhydride (TA) as the latent difunctional and trifunctional monomers, respectively. Caesium pivalate-catalysed ROACs of TA and excess epoxides were performed in the presence of an alcohol initiator at 80 °C in bulk. The obtained products, together with their linear counterparts (i.e., poly(phthalic anhydride-alt-epoxide)s), were characterised by NMR, viscometry, and light scattering. The results supported the successful synthesis of hyperbranched poly(TA-alt-epoxide)s. The versatility of the present HBPE synthesis was demonstrated by applying a range of alcohol initiators, such as typical diol and functional alcohols (e.g., poly(ethylene glycol) as a mono-alcohol or diol, and azido-/alkene-functionalised alcohols as another mono-alcohol), leading to HBPE-based block copolymers and functional HBPEs. Various epoxides, such as mono- and disubstituted alkylene oxides, glycidyl ether, and glycidyl amine, were found to be applicable in the present polymerisation system, which successfully produced HBPEs with different properties depending on the resulting backbone structure of the polymer.
  • Engineered ϵ-decalactone lipomers bypass the liver to selectively: In vivo deliver mRNA to the lungs without targeting ligands
    Mahmoud M. Abd Elwakil, Tianle Gao, Takuya Isono, Yusuke Sato, Yaser H.A. Elewa, Toshifumi Satoh, Hideyoshi Harashima
    Materials Horizons, 8, 8, 2251, 2259, Aug. 2021
    Scientific journal, RNA drugs hold real potential for tackling devastating diseases that are currently resistant to small molecule drugs or monoclonal antibodies. However, since these drugs are unstable in vivo and unable to pass through cellular membranes their clinical realization is limited by their successful delivery to target sites. Herein we report on the design of a combinatorial library of polyester lipomers based on the renewable monomer, ϵ-decalactone (ϵ-DL), via organocatalytic ring-opening polymerization for mRNA delivery. The ϵ-DL lipomers showed a surprisingly efficient ability to target the lungs upon intravenous administration. Interestingly, most of the lipomers achieved functional EGFP expression in the lungs, while minimally transfecting hepatocytes and splenic cells. This simple approach for the design of biodegradable materials has the potential for the clinical translation of genetic medicines for the treatment of lung diseases.

Other Activities and Achievements

  • Alkali Metal Carboxylates: Simple, Efficient, and Industrial Relevant Catalysts for Controlled Polymer Synthesis
    Feng Li, Ryota Suzuki, Tianle Gao, Xiaochao Xia, Takuya Isono, Toshifumi Satoh, Bulletin of the Chemical Society of Japan, 96, 9, 1003, 1018, 2023
    Polymer materials play a pivotal role in shaping modern society. The continuous development of polymer materials can be largely attributed to innovations in polymerization methods, especially in the development of new catalysts. When pursuing high-performance catalysts, it is crucial to consider their cost and safety for practical applications. Alkali metal carboxylates (AMCs) are widely available simple chemicals, and some of them are used as food additives. In the past few years, our group has demonstrated the ability of such simple compounds to catalyze the ring-opening polymerization of cyclic esters, cyclic carbonates, epoxides, and episulfides. Additionally, AMCs have demonstrated their efficacy in facilitating the ring-opening alternating copolymerization of cyclic anhydrides and cyclic ethers, resulting in the production of polyesters in a well-controlled manner. Moreover, AMCs can also catalyze the complicated self-switchable polymerization of a mixture of at least three monomers, yielding block copolymers with wellcontrolled block components and architectures. This account summarizes these successful examples, offering mechanistic insights and an outlook., Book review