A tough chitosan-alginate porous hydrogel prepared by simple foaming method

Abstract

Developing a robust, porous and biodegradable scaffold remains a significant challenge in bone tissue engineering. For this purpose, biodegradable and porous hydrogel has been researched for many years. However, it is still a big challenge to get a porous and robust hydrogel in a one-step method. The objective of this study is to prepare a porous hydrogel with a triple network using chitosan and alginate cross-linked by genipin and Ca2+ respectively and a simple foaming method was utilized to enrich porous structures. Besides, the optimum dosage of foaming agents and surfactant agents is studied to prepare a porous hydrogel with suitable pore size and high mechanical strength. Furthermore, the morphology, percentage porosity, swelling property, degradation profile and biocompatibility of the porous chitosan-alginate (CA) hydrogel has been assessed. The results show that the porous hydrogel prepared in this paper has pores with size of 45–280 ​μm and 91.16% porosity. The synthesis of triple network structure makes this hydrogel tough, and the wall stiffness of the dry porous CA hydrogel is 7.05 ​± ​0.084 ​MPa. The excellent biodegradability of chitosan and alginate makes the prepared hydrogel have good biodegradability and low cytotoxicity. These properties attest that this hydrogel might be an ideal candidate for tissue engineering.