报告题目：Click Synthesis, Stimuli-Sensitive Nanomedicine and Hydrogels of Nonlinear Biodegradable Block Copolymers
报告人：上海交通大学 董常明教授
时间：7月12日13:00
地点：嘉定校区化学楼二楼会议室
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董常明博士简介：于1972年9月出生，教授，博士生导师，教育部"新世纪优秀人才支持计划"获得者。2001年7月获北京大学高分子化学与物理博士学位；2002/03 ~ 2003/12在美国艾默蕾大学（Emory University）医学院外科系与生物医学工程系生物材料与组织工程研究室从事博士后研究工作；2003年12月加入上海交通大学化学化工学院高分子科学与工程系。目前，已在Macromolecules、Biomacromolecules、Adv. Funct Mat.、Small、Chem Comm、Biomaterials、J.Control. Rel.、J.Polym.Sci.Polym. Chem.、Polymer等国际高分子、生物材料领域的核心学术期刊发表论文50余篇，其中以第一作者和通讯作者发表IF>3论文40篇，论文被同行他引逾400次。
Abstract
Over the past three decades, dendritic polymers such as dendrimers, hyperbranched polymers, dendronized polymers, and linear-dendritic copolymers received much attention as they can be fabricated into multi-scale micro-/nano-structures and soft gels, which are useful modalities for diagnosis, drug/gene delivery, and tissue engineering. Herein, we highlighted our recent studies on nonlinear biodegradable block copolymers that were developed by utilizing click chemistry, importantly, which established a useful platform for stimuli-sensitive nanomedicine and hydrogels.
Using copper-catalyzed azide-alkyne cycloaddition (CuAAC), dendron-like/linear poly(γ-benzyl-L-glutamate)-b-poly(ethylene oxide) block copolymers with both asymmetrical and symmetrical topologies and their deprotected poly(L-glutamic acid)-b-poly(ethylene oxide) counterparts were successfully synthesized. A versatilestrategy was provided for the fabrication of pH-sensitive polypeptide-based normal micelles and reverse micelles from the same polypeptide-based block copolymersvia hydrogen-bonding interactions and/or host-guest chemistry. Moreover, we introduced a new concept of reverse micellar hydrogel and fabricated supramolecular polypeptide-based micellar hydrogels via the cooperation of host-guest chemistry and hydrogen-bonding interactions. These hydrogels can respond to dual stimuli, i.e., temperature and pH, and their mechanical and controlled drug-release properties can be tuned by the copolymer topology and the polypeptide composition.
On the other hand, multi-armed biodegradable block copolymers with a bioreducible core mPCL-b-PEO were for the first time synthesized by utilizing thiol-yne click chemistry. They self-assembled into bioreducible micelles and hydrogels in aqueous solution, which demonstrated tunable size, mechanical and drug-release properties. The DTT addition reduced the micelles to their half size without changing the morphology. The multi-armed copolymer formed the hydrogels with a higher mechanical strength (8 times) than the linear precursor, and the DTT addition also reduced the storage modulus. Importantly, the drug-release profile of the DOX-loaded micelles and/or hydrogels can be tuned by the multi-armed architecture and the bioreducible core of copolymer (or DTT), which provides a useful platform for stimuli-responsive nanomedicine and injectable drug delivery.