College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, 266109, China.
College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, 266109, China.
Carbohydr Polym. 2020 Oct 15;246:116586. doi: 10.1016/j.carbpol.2020.116586. Epub 2020 Jun 12.
Chitosan hydrogels fabricated by covalent crosslinking exhibit tough mechanical properties and chemical stability. In this paper, debranched starch (DBS) is oxidized to dialdehyde debranched starch (DADBS), which is used as a new type of a crosslinking agent to prepare hydrogels. Chitosan hydrogels with excellent properties are prepared by dynamic Schiff-base crosslinking between the aldehyde groups in DADBS and the amino groups in chitosan. Hence, chitosan hydrogels exhibit a rapid gelation ability, with a gelation time of less than 30 s, and their storage modulus increases with the gelation time. By adjusting the molar ratio of the amino group of chitosan to the aldehyde group of DADBS and the reaction temperature, the hydrogels exhibit tunable elasticity and mechanical properties. Notably, scanning electron microscopy revealed the presence of 100-200 nm microgels in the hydrogel network, which could exert a strengthening effect on the mechanical properties of the hydrogels. In addition, chitosan hydrogels exhibit a rapid self-healing ability and remarkable fluorescence properties; also, they can be 3D printed in different shapes. Overall, the DADBS cross-linked chitosan hydrogels demonstrate potential applications in food, medicine, agriculture, and materials.
壳聚糖水凝胶通过共价交联制成，具有坚韧的机械性能和化学稳定性。本文中，支链淀粉（DBS）被氧化为二醛支链淀粉（DADBS），后者被用作一种新型交联剂来制备水凝胶。通过 DADBS 中的醛基与壳聚糖中的氨基之间的动态席夫碱交联，制备出具有优异性能的壳聚糖水凝胶。因此，壳聚糖水凝胶具有快速的凝胶化能力，凝胶化时间小于 30 秒，其储能模量随凝胶化时间的增加而增加。通过调整壳聚糖的氨基与 DADBS 的醛基的摩尔比和反应温度，可以调节水凝胶的弹性和机械性能。值得注意的是，扫描电子显微镜显示水凝胶网络中存在 100-200nm 的微凝胶，这对水凝胶的机械性能有增强作用。此外，壳聚糖水凝胶具有快速的自修复能力和显著的荧光性能，并且可以 3D 打印成不同的形状。总的来说，DADBS 交联的壳聚糖水凝胶在食品、医药、农业和材料领域具有潜在的应用。
