Department of Mechanical and Industrial Engineering, Materials Science and Technology Laboratory, University of Brescia, Via Branze 38, 25123, Brescia, Italy.
Department of Applied Chemistry and Chemical Engineering, Faculty of Science, University of Chittagong, Chittagong, 4331, Bangladesh.
Macromol Biosci. 2019 Aug;19(8):e1900099. doi: 10.1002/mabi.201900099. Epub 2019 Jul 12.
Rational design and development of tailorable simple synthesis process remains a centerpiece of investigational efforts toward engineering advanced hydrogels. In this study, a green and scalable synthesis approach is developed to formulate a set of gelatin-based macroporous hybrid hydrogels. This approach consists of four sequential steps starting from liquid-phase pre-crosslinking/grafting, unidirectional freezing, freeze-drying, and finally post-curing process. The chemical crosslinking mainly involves between epoxy groups of functionalized polyethylene glycol and functional groups of gelatin both in liquid and solid state. Importantly, this approach allows to accommodate different polymers, chitosan or hydroxyethyl cellulose, under identical benign condition. Structural and mechanical anisotropy can be tuned by the selection of polymer constituents. Overall, all hydrogels show suitable structural stability, good swellability, high porosity and pore interconnectivity, and maintenance of mechanical integrity during 3-week-long hydrolytic degradation. Under compression, hydrogels exhibit robust mechanical properties with nonlinear elasticity and stress-relaxation behavior and show no sign of mechanical failure under repeated compression at 50% deformation. Biological experiment with human bone marrow mesenchymal stromal cells (hMSCs) reveals that hydrogels are biocompatible, and their physicomechanical properties are suitable to support cells growth, and osteogenic/chondrogenic differentiation, demonstrating their potential application for bone and cartilage regenerative medicine toward clinically relevant endpoints.
可定制的简单合成工艺的合理设计和开发仍然是工程先进水凝胶研究努力的核心。在这项研究中，开发了一种绿色且可扩展的合成方法，以配制一系列基于明胶的大孔混合水凝胶。该方法包括从液相预交联/接枝、单向冷冻、冷冻干燥，最后后固化过程的四个连续步骤。化学交联主要涉及在液体和固体状态下，功能化聚乙二醇的环氧基团与明胶的官能团之间。重要的是，这种方法允许在相同的良性条件下容纳不同的聚合物、壳聚糖或羟乙基纤维素。通过选择聚合物成分可以调整结构和机械各向异性。总体而言，所有水凝胶均表现出合适的结构稳定性、良好的溶胀性、高孔隙率和孔连通性，并且在长达 3 周的水解降解过程中保持机械完整性。在压缩下，水凝胶表现出强大的机械性能，具有非线性弹性和应力松弛行为，在 50%变形的重复压缩下没有出现机械失效的迹象。与人类骨髓间充质基质细胞（hMSCs）的生物学实验表明，水凝胶具有生物相容性，其物理机械性能适合支持细胞生长和成骨/软骨分化，表明它们在骨和软骨再生医学方面具有潜在的应用，以达到临床相关终点。
