Cotton cellulose nanofiber/chitosan scaffolds for skin tissue engineering and wound healing applications

Chitosan (CS) is a promising polymeric biomaterial for use in scaffolds for<i>in vitro</i>skin models and wound dressings, owing to its non-antigenic and antimicrobial properties. However, CS often exhibits insufficient physicochemical properties, mechanical strength, and bioactivity, limiting its efficacy in demanding applications. To address these challenges, cotton cellulose nanofibers (CNFs) represent a promising nanomaterial for enhancing CS-based scaffolds in tissue engineering. CNF offers superior stiffness, and mechanical properties that enhance cellular adhesion and proliferation, both crucial for effective tissue regeneration and healing. This study aimed to develop and characterize a scaffold combining cotton CNF and CS, focusing on its cytocompatibility with human fibroblasts and keratinocytes. The cotton CNF/CS scaffold was fabricated using the casting technique, and its physicochemical properties and cellular compatibility were assessed<i>in vitro</i>. The results demonstrated that incorporating cotton CNF significantly enhanced the stability of the CS matrix. The CS scaffold with 1000 μg ml^-1of cotton CNF exhibited increased roughness and reduced rupture strain compared to the pure CS scaffold. The cotton CNF/CS scaffold effectively promoted the adhesion, viability, proliferation, migration, and collagen synthesis of skin cells. Notably, increased cell viability was observed in human fibroblasts cultured on scaffolds with higher concentrations of cotton CNF (100 and 1000 μg ml^-1). Based on the findings, the cotton CNF/CS scaffold demonstrates enhanced physicochemical properties and bioactivity, making it a promising candidate for the development of<i>in vitro</i>human skin models and wound healing dressings.