Preparation and characterization of self-healing nanocomposite hydrogels based on chitosan/polyethylene...

Hydrogels used for wound dressing applications often suffer from limited mechanical stability and insufficient self-repair capability, which restricts their long-term performance in dynamic physiological environments. This research aimed to prepare self-healing nanocomposite hydrogels based on chitosan, polyethylene glycol (PEG), and bacterial nanocellulose (BNC). For this purpose, PEG was first modified by an aldehyde agent, resulting in benzaldehyde-functionalized PEG (BM-PEG), to deliver bonding potential with the amine groups of chitosan. Nanocomposite hydrogels were then prepared by vortexing at different compositions with BNC as a reinforcing agent. Fourier transform infrared (FTIR) analysis confirmed the successful formation of chemical bonds between the components. Scanning electron microscopy (SEM) micrographs revealed that incorporating BNC up to an optimal percentage increased the average pore size of the hydrogels and improved their compressive strength and storage modulus. Self-healing behavior was qualitatively evaluated through a cut-and-heal test, showing visible rebonding of the hydrogel networks. Moreover, the incorporation of BNC into the hydrogels increased the rate of self-healing, making the cutoff hardly detectable. The suitable biocompatibility and cell adhesion of the fabricated hydrogels were demonstrated through in vitro cell studies. Accordingly, nanocomposite hydrogels have been suggested as favorable candidates for wound dressing-related biomedical applications.