Fabrication, Characterization of Chitosan/Nanosilver Film and Its Potential Antibacterial Application

In this work chitosan/silver nanoparticle films were synthesized by a simple photochemical method of reduction of silver ions in an acidic solution of AgNO3 and chitosan. This is a novel, cheap, easy, quick and in situ approach to prepare chitosan films loaded with silver nanoparticles (AgNPs). Chitosan used here is a natural polymer and acts as a very good chelating and stabilizing agent; thus, this approach of formation of chitosan/silver nanoparticle films is proved to be an excellent 'green approach' for the synthesis of metal nanoparticle composites. The presence of silver nanoparticles was confirmed from the transmission electron microscopy (TEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) of the film. The surface plasmon resonance (SPR) obtained at 400 nm also confirmed the presence of nanosilver in the chitosan film. The developed chitosan-nanosilver films demonstrated excellent antibacterial action against model bacteria, Escherichia coli and Bacillus. This approach can be easily used in the large-scale production of such silver-nanoparticles-loaded chitosan films. These films can be used as antimicrobial packaging materials, as wound dressings and can also be grafted onto various implants. (C) Koninklijke Brill NV, Leiden, 2009