Design and development of a piscine collagen blended pullulan hydrogel for skin tissue engineering

Abstract

This present study was designed to prepare a super-absorbent tailor-made collagen–pullulan hydrogel with improved mechanical stability and well-defined biocompatibility for skin tissue engineering. Three-dimensional (3D) scaffolds were fabricated using natural polysaccharide pullulan, cross-linked with sodium trimetaphosphate (STMP) and blended with collagen to form a polymeric network. Collagen was extracted from the skin of unexplored puffer fish (Lagocephalus inermis). The cross-linking occurred at alkaline pH at room temperature to give translucent, clear and soft hydrogels. Swelling studies revealed a remarkable water absorption property with a swelling ratio up to 320%, an ideal characteristic for the hydrogel to provide a moist wound healing environment. SEM analysis revealed the highly interconnected porous structure of the collagen blended pullulan hydrogels. MTT assay performed on NIH3T3 fibroblast cell lines revealed that the prepared hydrogels were 100% biocompatible with enhanced cell adhesion and proliferation. The hydrogels promote angiogenesis in the chick chorioallantoic membrane, which was investigated by the CAM assay. Wound healing studies exhibit a statistically significant (<0.05) response to wound contraction and re-epithelialization in an excision wound model in rats. Compared with 49% wound closure in 11 ± 2 days in the controls, 96% wound closure was observed in rats treated with the collagen–pullulan hydrogel (CGPNH). The highly porous collagen–pullulan hydrogels were successfully developed with a significant in vitro and in vivo biological performance, and are a promising biomaterial for wound healing applications.