Department of Materials and Pharmaceutical Chemistry , Institute of Applied Materials Science, Vietnam Academy of Science and Technology , Ho Chi Minh, Vietnam.
J Biomater Sci Polym Ed. 2013;24(14):1636-48. doi: 10.1080/09205063.2013.789356. Epub 2013 Apr 22.
In recent years, injectable chitosan-based hydrogels have been widely studied towards biomedical applications because of their potential performance in drug/cell delivery and tissue regeneration. In this study, we introduce a simple and organic solvent-free method to prepare tyramine-tetronic-grafted chitosan (TTeC) via activation of four terminal hydroxyl groups of tetronic, partial tyramine conjugate into the activated product and grafting the remaining activated moiety of tetronic-tyramine onto chitosan. The grafted copolymer was well characterized by UV-Visible, (1)H NMR, and Thermogravimetric analysis. The aqueous TTeC copolymer solution rapidly formed hydrogel in the presence of horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) at physiological conditions. The gelation time of the hydrogel was performed within a time period of 4-60 s, when the concentrations of HRP, H2O2, and polymers varied. The hydrogel exhibited highly porous structure which could be controlled by using H2O2. In vitro cytotoxicity study with Human Foreskin Fibroblast cell using live/dead assay indicated that the hydrogel had high cytocompatibility and could play a role as a scaffold for cell adhesion. The injectable hydrogels did not cause any inflammation after two weeks and one day of the in vivo injection. The obtained results demonstrated a great potential of the TTeC hydrogel in biomedical applications.
近年来，由于在药物/细胞递送和组织再生方面的潜在性能，可注射壳聚糖基水凝胶已被广泛研究用于生物医学应用。在本研究中，我们通过激活四元环的四个末端羟基，将多巴胺-四元环接枝到壳聚糖（TTeC）上，介绍了一种简单且无有机溶剂的方法。部分多巴胺与活化产物偶联，将剩余的四元环-多巴胺活化部分接枝到壳聚糖上。接枝共聚物通过紫外可见分光光度计、（1）H NMR 和热重分析进行了很好的表征。在辣根过氧化物酶（HRP）和过氧化氢（H2O2）存在下，水相 TTeC 共聚物溶液在生理条件下迅速形成水凝胶。当 HRP、H2O2 和聚合物的浓度发生变化时，水凝胶的凝胶时间在 4-60 s 内完成。水凝胶具有高度多孔结构，可通过使用 H2O2 进行控制。通过使用活/死测定法对人包皮成纤维细胞进行体外细胞毒性研究表明，水凝胶具有良好的细胞相容性，并可用作细胞黏附的支架。在体内注射两周和一天后，可注射水凝胶不会引起任何炎症。研究结果表明，TTeC 水凝胶在生物医学应用中有很大的潜力。
