Radiation synthesis of nanosilver/poly vinyl alcohol/cellulose acetate/gelatin hydrogels for wound dressing

Ag nanoparticles (AgNPs) supported within polyvinyl alcohol/cellulose acetate/gelatin (PVA/CA/GEL) composite have been successfully synthesized using gamma radiation-induced crosslinking as novel in situ method. The reduction of Ag⁺ ions within the previously obtained hydrogel matrix was performed using further radiation. The successful incorporation of silver nanoparticles in PVA/CA/GEL matrix was confirmed by UV–Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscope (TEM), energy dispersive X-ray (EDX) analysis and Fourier transform infrared (FTIR) spectroscopy. It was found that PVA/CA/GEL-stabilized silver nanocomposite hydrogel revealed the presence of well-dispersed and spherical silver nanoparticles, the mean diameter and size distribution of nanoparticles increased with enhanced loaded AgNO₃ concentration. The mean diameters of 5, 10 and 20 mM AgNO₃ loaded PVA/CA/GEL were 38.6 nm, 56.8 nm and 60.1 nm whereas, 25 % of size distribution was < 37.0 nm, < 60.7 nm and < 63.0 nm, respectively. The mechanical properties of the membranes were characterized by tensile tests; the hydrogel membrane had sufficient strength. TGA showed a higher thermal stability for Ag/PVA/CA/GEL nanocomposite than the conventional ones. XRD results indicated that Ag-nano particle inhibit the crystallization of PVA-based gel and presence of silver nano-particle in the hydrogel nanocomposite. The nanosilver/PVA/CA/GEL hydrogels were found to have antimicrobial activity against various fungus and bacteria. The antibacterial ability could be significantly enhanced by the increasing of AgNO₃ content. In vitro bacterial adhesion study indicated a significant difference between neat and nanocomposite gel which showed higher inhibition. It suggested that the nanosilver hydrogels could be tried as wound dressing.