Abstract Silver nanoparticle gels are a novel form of plant-based biopesticide that can be used as an alternative to chemical-based pesticides for the treatment of fungal diseases on tomato plants. In this investigation, our attention will be focused on the preparation and evaluation of colloidal silver nanoparticles as antibacterial and antifungal agents. The colloidal silver nanoparticles have been prepared employing standard chemical reduction methods. The colloidal silver nanoparticles were characterized using transmission electron microscopy TEM, zeta potential, photo correlation spectroscopy PCS, and in vitro release kinetics. The particles thus obtained were spherical in shape and having an average particles size of 5-20 nm, zeta potentials of -25.5 to -38.3 mV, and the release kinetics was following zero order kinetics with r 2 >0.96. The dissolution data indicates that the release of the silver nanoparticles is inversely correlated with the size of the nanoparticles i.e. the release increased with smaller particles. The results suggest that the Ag NPs would be stable in the pharmaceutical preparations and will be easily to the infection site. The colloidal silver nanoparticles were found to be very efficient antibacterial agents for different types of bacteria. The bacteria studied were namely: E. coli, S. coccus, Salmonellae, and P. aeruginosa. The associated antifungal effects were also investigated for Aspergillus and Pencillium. Cytotoxicity of the nanoparticle was studied using human fibroblast cell line. It was concluded that cytotoxicity is concentrations dependant. The results provided strong evidence that could warrant the consideration of silver nanoparticles as antibacterial and antifungal agent that could circumvent the side and passive effects of the conventional antibiotics.
Keywords Formulation, Evaluation, Silver Nanoparticles, Topical Fungal Disease.