Adipic acid interaction enhances the mechanical and thermal stability of natural polymers

Application of biopolymers for biomedical applications limits with the functional and structural properties of the materials. Crosslinkers are used to provide the requisite properties. The question on biocompatibility of the existing crosslinkers necessitates the need for alternative crosslinkers. In the present study, adipic acid was chosen as crosslinker and evaluated the mode of interaction with chitosan and type-I collagen. A 3D scaffold biopolymer material was prepared using chitosan at 1.0% (w/v) and adipic acid at 0.2% (w/v), similarly collagen 0.5% (w/v) and adipic acid 0.2% (w/v) displayed an improved mechanical strength and in addition found biocompatible for NIH 3T3 fibroblast cells. The chemistry behind the interaction and the characteristics of the biopolymer material obtained upon crosslinking suggests that noncovalent interactions play the major role in deciding the property of the said materials and their suitability for biomedical applications.