Enzymatically obtaining hydrogels of PVA crosslinked with ferulic acid in the presence of laccase for biomedical applications

Hydrogels are three-dimensional natural or synthetic polymeric materials with numerous medical and biological applications, such as the ophthalmic area. In this context, a hydrogel using polyvinyl alcohol (PVA) and ferulic acid in the presence of laccase was obtained. The concentrations of PVA, laccase, and ferulic acid were modified, and their effects were analyzed in terms of refractive index, density, and dynamic viscosity. The best condition for obtaining the hydrogel was 12.0% of PVA (w/w), laccase concentration of 836 mu g mL(-1), and ferulic acid concentration of 1.95 mM. The rheological measurements confirmed the PVA reticulation with ferulic acid in the presence of laccase, as it promoted an increase in viscosity. On the other hand, the reaction stimulated a decrease in the swelling degree, crystallinity, and melting temperature. Therefore, these results confirm the formation of crosslinks among the PVA chains.