ANTIFUNGAL ACTIVITIES OF SILVER NANOPARTICLES OBTAINED BY PULSED LASER ABLATION IN LIQUID.

Nanostructures of noble metals are being investigated for their applications in areas of biology and biotechnology, biological labeling, photothermal, photonics, optoelectronics, catalysis, surface-enhanced Raman scattering (SERS) detection etc. Among the metal nanoparticles, silver nanoparticles are well known for their size dependent properties as well as antibacterial activities. Pulsed laser ablation in liquid (PLAL) is a physical synthesis technique to obtain ultra-pure nanoparticles of metals, semiconductors and ceramics which is a green synthesis compared to other chemical methods. In this chapter, we describe antifungal activities of silver nanoparticles produced by pulsed laser ablation of a high purity silver target in distilled water. The chapter includes details of the synthesis of silver nanocolloids using PLAL and their characterization using various techniques. Antifungal activities of these silver nanocolloids on fungi such as Aspergillus niger and Penicillium spp are explained. These filamentous fungi are responsible for the deterioration of storage life of fruits and vegetables worldwide. The effects of heterogeneous shaped silver nanoparticles produced by PLAL in these two fungal species probed in vitro are discussed. The nanoparticle concentrations from 31.8 to 74.2 mg/L were able to delay mycelium growth and sporulation in both species at the conditions probed. These results open up more biological applications of nanoparticles synthesized by PLAL. [ABSTRACT FROM AUTHOR]