Nanocomposite hydrogel based on chitosan/laponite for sealing and repairing tracheoesophageal fistula.

Tracheoesophageal fistula (TEF) is an abnormal connection between the trachea and esophagus that severely impairs quality of life. Current treatment options have limitations, including conservative treatment, surgical repair, and esophageal stent implantation. Here, we introduced laponite (LP) nano-clay to improve chitosan-based hydrogels' rheological properties and mechanical properties and developed an endoscopically injectable nanocomposite shear-thinning hydrogel to seal and repair fistulas as an innovative material for the treatment of TEF. Excellent injectability, rheological properties, mechanical strength, self-healing, biodegradability, biocompatibility, and tissue repair characterize the new hydrogel. The introduction of LP nano-clay improves the gel kinetics problem of hydrogels to realize the sol-gel transition immediately after injection, avoiding gel flow to non-target sites. The addition of LA nano-clay can significantly improve the rheological properties and mechanical strength of hydrogels, and hydrogel with LP content of 3 % shows better comprehensive performance. The nanocomposite hydrogel also shows good cytocompatibility and can promote wound repair by promoting the migration of HEEC cells and the secretion of VEGF and FGF. These findings suggest that this nanocomposite hydrogel is a promising biomaterial for TEF treatment.