Abstract:

Silver nanoparticles/bacterial cellulose(n-Ag/BC) composite membranes were prepared and cha-racterized. Silver nanoparticles were synthesized in situ through the reaction of Tollens’ reagent with aldehydes, under ambient conditions in nanoporous bacterial cellulose membrances as nanoreactors. Sliver nanoparticle was readily obtained and grew into the BC network by the precipitation of above reaction products. BC films were prepared and loaded with ca. 0.14 mg/cm² to ca. 0.42 mg/cm² of silver nanoparticles. XRD patterns indicated the existence of Ag⁰ nanoparticles in the BC, and the diameter of the silver nanoparticles is ca. 31.8 nm. Scanning electron microscopy(SEM) images showed that the sliver nanoparticles(size range dozens nm) well dispersed in the network of BC. The sliver nanoparticle-impregnated BC membranes exhibited high hydrophilic ability and strong antimicrobial activity. Bacterial killing efficiencies of the silver loaded films were investigated against staphylococcus aureus. It was determined that as little as ca. 0.14 mg/cm² of silver in the BC films caused a reduction of 99% bacteria in suspensions incubated in contact with the films. Significantly, the n-Ag/BC antimicrobial membranes were good biocompatibility, and allowed the attachment and growth of the epidermal cells. The result shows an easy method to synthesis silver nanoparticles into BC membranes. The n-Ag/BC has stability, antimicrobial activity and biological properties. The preparative procedure is facile, and provides a simple route to manufacturing of useful antimicrobial membranes, which would be a good alternative for antimicrobial wound dressing.

Key words: Bacterial cellulose, Silver nanoparticles, Crystal growth, Antibacterial activity, Biocompatibility