Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Syzygium nervosum DC. leaf extract reinforces chitosan–glutaric anhydride hydrogels by enhancing crosslinking density and structural integrity while reducing pore size and water uptake. The developed hydrogels exhibit antioxidant and antibacterial activities, diffusion-controlled release behavior, and good cytocompatibility, highlighting their potential as bioactive burn wound dressings.

ABSTRACT
Burn wound management requires dressing materials capable of maintaining structural integrity, regulating moisture, and mitigating infection and oxidative stress. However, conventional chitosan–based hydrogels often exhibit limited mechanical stability and functional performance. This study investigated the influence of Syzygium nervosum DC. leaf extract (SNE) on the physicochemical characteristics and in vitro performance of chitosan–glutaric anhydride (CG) hydrogels developed for burn wound dressing applications. Incorporation of SNE effectively reinforced the hydrogel matrix while enhancing biological functionality. At 7% SNE loading, the swelling ratio decreased from 0.42 ± 0.02 g/g to 0.21 ± 0.01 g/g, accompanied by an increase in gel content from 36.63% ± 1.54% to 52.89% ± 3.77%, indicating enhanced crosslinking efficiency. Scanning electron microscopy revealed a more compact and interconnected network with reduced pore size from 20.55 ± 1.00 μm to 7.09 ± 0.22 μm, contributing to restricted water uptake and improved structural integrity. Fourier–transform infrared spectroscopy further confirmed intermolecular interactions between chitosan functional groups and SNE constituents. Functionally, SNE-loaded hydrogels exhibited antioxidant activity, diffusion-controlled release behavior, and antibacterial activity against Escherichia coli and Staphylococcus aureus, while maintaining good cytocompatibility toward L929 fibroblast cells. These findings support the potential of SNE-loaded CG hydrogels as bioactive burn wound dressings.