Fabrication and evaluation of homogeneous alginate/polyacrylamide–chitosan–gelatin composite hydrogel scaffolds based on the interpenetrating networks for tissue engineering

Abstract

AbstractInterpenetrating polymer network (IPN) is generally considered to be one of the most effective methods for imparting high‐strength mechanical properties to hydrogel materials. To broaden the application of alginate hydrogel in skeletal muscle or muscle tissue engineering, the interpenetrating network technology and layer‐by‐layer (LBL) electrostatic assembly were proposed to fabricate the homogeneous alginate/polyacrylamide–chitosan–gelatin (Alg/PAAM–CS–GT) composite hydrogel scaffolds, using the hydroxyapatite/d‐glucono‐δ‐lactone (HAP/GDL) complex as the gelling system. The effects of different components of alginate/polyacrylamide (Alg/PAAM) on the morphology, mechanical properties, swelling, degradability, and cytocompatibility of the hydrogel scaffolds were comparatively characterized. Experimental results showed that the as‐prepared Alg/PAAM–CS–GT composite hydrogel scaffolds exhibited sharp edges and regular 3D structures. Their pore structure could be regulated by changing the content of PAAM in Alg/PAAM–CS–GT composite hydrogel scaffolds. And the filling of PAAM reduced the pores and thickened the pore walls, which obviously enhanced the mechanical properties of Alg/PAAM–CS–GT composite hydrogel scaffolds. FT‐IR and thermogravimetric analysis showed that O‧‧‧N hydrogen bonding between COOH of SA and NH2 of PAAM could be helpful to improve the thermal stability of the composite hydrogel scaffolds. The swelling and biodegradation measurements indicated that the swelling and degradation of Alg/PAAM–CS–GT composite hydrogel scaffolds could be effectively regulated by changing the component content of the composite hydrogel. In addition, the in vitro cytocompatibility analysis showed that the Alg/PAAM–CS–GT composite hydrogel scaffolds could support the growth of MC3T3‐E1 cells and promote cell proliferation and differentiation. According to the in vitro cytocompatibility test results, the optimum PAAM content for the Alg/PAAM–CS–GT composite hydrogel scaffolds was 60%. Because of good morphology, well‐developed pores, excellent mechanical properties, and high biological activity of Alg/PAAM–CS–GT composite hydrogel scaffolds, they could be suitable for application in the tissue engineering field.