Study of shape of zinc oxide nanoparticles on the in-vitro and in-vivo performance of polymeric hydrogels for wound dressing.

Extensive fluid loss, tissue damage, and bacterial infection are some important aspects that need to be addressed for designing ideal burn wound dressings. Hydrogel-based dressings cater to most of these functions; additionally, the incorporation of metal oxide nanoparticles (NPs) provides antibacterial properties that enhance the performance of wound dressings. We report here for the first time, how by employing different shapes of ZnO NPs, viz quasi-spherical, floral, and rods; in hydrogels made of PVA - P(AMPS) (Poly (vinyl alcohol) (PVA) - Poly (2-Acrylamido-2-Methyl Propane Sulfonic Acid)) along with g-C₃N₄, one could correlate structure-property relationships to wound healing efficiency. The incorporation of g-C3N4 was to enhance the thermo-mechanical stability of hydrogel, Maximum tensile strength of the hydrogel was obtained for 150 mg of g-C3N4 incorporated hydrogels, same amount being used for other systems studied. The impact of the incorporation of different shapes and amounts of ZnO NPs on the hydrogels has been studied and our results show maximum swelling ability (∼110 %), high moisture retention capacity (>90 %), and moderate water vapor transmission rate (82 g/m²h) for selected systems. Among these different shapes incorporated hydrogels, remarkable enhancement in tensile strength (76 %) was observed for quasi-spherical ZnO NPs incorporated hydrogels compared to bare. These hydrogels showed high cell viability (>70 %), high antibacterial activities against E. coli and S. aureus, and high wound healing efficiency (>80 %) in an in-vivo rat model, proving their potential to be used in wound dressing applications.