Synthesis and Characterization of Antimicrobial Polyvinyl Pyrrolidone Hydrogel as Wound Dressing

Novel antimicrobial PVP-GP hydrogels were prepared by polycondensation of hexamethylenediamine and guanidine hydrochloride, followed by cross-linking reaction using N-vinyl pyrrolidone (NVP) and N,N’-methylene bisacrylamide (MBAm). The products were characterized by 1H NMR, FTIR, SEM, and their performances for wound dressing applications were also evaluated. Swelling study showed that the water absorptivity of the hydrogels decreased as the cross-linking density increased either in water or in physiological saline solution. Both PVP and PVP-GP hydrogels possessed excellent mechanical strength which could address the requirements for wound dressing. The water vapor transmission rates (WVTR) of PVP and PVP-GP hydrogels were in the range of 1727–2320 g/m2/day, indicating that the prepared hydrogels were suitable for wound dressings without dehydrating the wound surface or accumulating exudates. Kirby-Bauer inhibition zone test and microbe penetration assay proved that the PVP-GP hydrogels had high antimicrobial activity.