Green synthesis of in situ forming alginate-urethane hydrogel through Schiff base reaction

Despite recent advances in preparing hydrogels, their application is mainly limited due to the poor mechanical properties or the high risk of inflammatory response. Therefore, in this study a fully defined in situ hydrogelation system is developed based on green-chemistry in which alginate dialdehyde (ADA) was coupled to an isocyanate-free urethane derivative. FTIR analysis along with (HNMR)-H-1 confirmed hydrogel formation. Improved thermal stability of the hydrogel was an indication of hydrogen bonding at various sites. The microgels possessed the mean diameter of 4 microns, reasonable gelation time and suitable biocompatibility which made them prospective candidates for various fields of biomedicine. (C) 2019 Published by Elsevier B.V.