Xu Huan, Zhang Lina, Cai Jie
College of Chemistry & Molecular Sciences, Wuhan University, Wuhan 430072, China.
Research Institute of Shenzhen, Wuhan University, Shenzhen 518057, China.
ACS Appl Bio Mater. 2019 Jan 22;2(1):196-204. doi: 10.1021/acsabm.8b00548. Epub 2019 Jan 2.
Dynamic chemistry has been recently applied to design injectable hydrogels capable of self-healing. Among current strategies for preparing hydrogels that are suitable for cell encapsulation and culture, the fabrication of injectable, self-healing hydrogels is immensely superior. Here, novel β-chitin-based, injectable, self-healing hydrogels were constructed through the self-assembly and entanglement of amphiphilic quaternized β-chitin (QC) and hydrophilic oxidized dextran (OD) chains as well as the dynamic Schiff base linkages without extra additives under physiological conditions. The gelation time, viscoelastic behavior, mechanical properties, biodegradability, stimulus sensitivity, shear-thinning ability and self-healing properties of the QC/OD hydrogels were thoroughly characterized. Moreover, the QC/OD hydrogels could be applied for the controlled pH-sensitive release of doxorubicin hydrochloride. Because of the excellent cytocompatibility, the QC/OD hydrogels were further used as a promising platform for the three-dimensional encapsulation and culture of NIH-3T3 cells and mouse bone marrow-derived mesenchymal stem cells. Specifically, these novel β-chitin-based hydrogels can be used as an antibacterial vehicle for the delivery of cells in the gel form and thus have potential for applications in regenerative medicine, drug/gene/cell delivery, and cell therapy.
动态化学最近已被应用于设计具有自愈能力的可注射水凝胶。在目前制备适用于细胞封装和培养的水凝胶的策略中，可注射、自愈水凝胶的制备具有极大的优势。在此，通过两亲性季铵化β-甲壳素（QC）和亲水性氧化葡聚糖（OD）链的自组装和缠结以及在生理条件下无需额外添加剂的动态席夫碱键合，构建了新型的基于β-甲壳素的可注射、自愈水凝胶。对QC/OD水凝胶的凝胶化时间、粘弹性行为、力学性能、生物降解性、刺激敏感性、剪切稀化能力和自愈性能进行了全面表征。此外，QC/OD水凝胶可用于盐酸阿霉素的pH敏感控释。由于具有优异的细胞相容性，QC/OD水凝胶进一步被用作NIH-3T3细胞和小鼠骨髓间充质干细胞三维封装和培养的有前景的平台。具体而言，这些新型的基于β-甲壳素的水凝胶可以用作抗菌载体，以凝胶形式递送细胞，因此在再生医学、药物/基因/细胞递送和细胞治疗中具有应用潜力。
