Combining antioxidant hydrogels with self-assembled microparticles for multifunctional wound dressings

A multi-functional composite to be employed as a dressing material was prepared by combining hydrogel and microparticle systems. For the synthesis of the hydrogel counterpart, a free radical polymerization was carried out using a gelatin–curcumin conjugate, previously obtained through immobilized laccase catalysis, and polyethylene glycol dimethacrylate as a functional element, plasticizer, and crosslinker. The hydrogel was found to possess high water affinity, biocompatibility, and the ability to reduce the H2O2-induced oxidative stress on MRC-5 cells by 30%. The spherical microparticle system (mean diameter of 1.75 μm) was prepared by self-assembly of a keratin-methacrylated polyethylene glycol-40 stearate derivative synthesized by a free radical reaction. The final composite, prepared by absorption of microparticles on the hydrogel system, was found to be effective as a support for enhanced cell growth (3.5 times). Furthermore, a reduction of methicillin-resistant Staphylococcus aureus proliferation by 1 log10 CFU was reached taking advantage of the sustained release of the antimicrobial quercetin.