Polyvinyl pyrrolidone/carrageenan blend hydrogels with nanosilver prepared by gamma radiation for use as an antimicrobial wound dressing

Hydrogels were prepared using polyvinyl pyrrolidone (PVP) blended with carrageenan by gamma irradiation at different doses of 25 and 40kGy. Gel fraction of hydrogels prepared using 10 and 15% PVP in combination with 0.25 and 0.5% carrageenan was evaluated. Based on gel fraction, 15% PVP in combination with 0.25% carrageenan and radiation dose of 25kGy was selected for the preparation of hydrogels with nanosilver. Radiolytic synthesis of silver nanoparticles within the PVP hydrogel was carried out. The hydrogels with silver nanoparticles were assessed for antimicrobial effectiveness and physical properties of relevance to clinical performance. Fluid handling capacity (FHC) for PVP/carrageenan was 2.35 +/- 0.39-6.63 +/- 0.63g/10cm(2) in 2-24 h. No counts for Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and Candida albicans were observed in the presence of hydrogels containing 100ppm nanosilver after 3-6 h. The release of silver from hydrogels containing 100ppm nanosilver was 20.42 +/- 1.98ppm/100cm(2) in 24 h. Hydrogels containing 100ppm nanosilver with efficient FHC demonstrated potential microbicidal activity (3 log(10) decrease in CFU/ml) against wound pathogens, P. aeruginosa, S. aureus, E. coli, and C. albicans. PVP/carrageenan hydrogels containing silver nanoparticles can be used as wound dressings to control infection and facilitate the healing process for burns and other skin injuries.