Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
Polymer program, Institute of Materials Science, University of Connecticut, 25 King Hill Road, Unit 3136, Storrs, Connecticut 06269-3136, United States.
ACS Appl Mater Interfaces. 2024 Feb 7;16(5):6674-6686. doi: 10.1021/acsami.3c18954. Epub 2024 Jan 30.
Peptide-based hydrogels have great potential for applications in tissue engineering, drug delivery, and so on. We systematically synthesize, characterize, and investigate the self-assembly behaviors of a series of polypeptide-based penta-block copolymers by varying block sequences and lengths. The copolymers contain hydrophobic blocks of poly(γ-benzyl-l-glutamate) (PBG, B) and two kinds of hydrophilic blocks, poly(l-lysine) (PLL, K) and poly(ethylene glycol) (PEG, EG), where and are the number of repeating units of each block, where PBG and PLL blocks have unique functions for nerve regeneration and cell adhesion. It shows that a sufficient length of the middle hydrophilic segment capped with hydrophobic end PBG blocks is required. They first self-assemble into flower-like micelles and sequentially form transparent hydrogels (as low as 2.3 wt %) with increased polymer concentration. The hydrogels contain a microscale porous structure, a desired property for tissue engineering to facilitate the access of nutrient flow for cell growth and drug delivery systems with high efficiency of drug storage. We hypothesize that the structure of B-K-EG-K-B agglomerates is beyond micron size (transparent), while that of K-B-EG-B-K is on the submicron scale (opaque). We establish a working strategy to synthesize a polypeptide-based block copolymer with a wide window of sol-gel transition. The study offers insight into rational polypeptide hydrogel design with specific morphology, exploring the novel materials as potential candidates for neural tissue engineering.
基于肽的水凝胶在组织工程、药物输送等方面具有巨大的应用潜力。我们通过改变嵌段序列和长度，系统地合成、表征和研究了一系列基于多肽的五嵌段共聚物的自组装行为。这些共聚物包含疏水性嵌段聚（γ-苄基-l-谷氨酸）（PBG，B）和两种亲水性嵌段，聚（l-赖氨酸）（PLL，K）和聚（乙二醇）（PEG，EG），其中 和 分别为每个嵌段的重复单元数，其中 PBG 和 PLL 嵌段具有促进神经再生和细胞黏附的独特功能。结果表明，需要足够长度的中间亲水性段，其被疏水性末端 PBG 段封端。它们首先自组装成花状胶束，然后随着聚合物浓度的增加，依次形成透明水凝胶（低至 2.3wt%）。水凝胶具有微尺度多孔结构，这是组织工程的理想特性，有利于营养物质的流动，促进细胞生长，并具有高效的药物储存药物输送系统。我们假设 B-K-EG-K-B 聚集体的结构超出了微米级（透明），而 K-B-EG-B-K 的结构处于亚微米级（不透明）。我们建立了一种用于合成具有宽溶胶-凝胶转变窗口的基于多肽的嵌段共聚物的工作策略。该研究为具有特定形态的理性多肽水凝胶设计提供了思路，探索了作为神经组织工程潜在候选材料的新型材料。
