Microbial Synthesis of Pt Nanoparticles – A Nano Review

Green synthesis is an alternative way to reduce the formation of harmful chemical products by using eco-friendly procedures for the synthesis. Microbial synthesis is one of the green methods to avoid pollution. In microbial synthesis of nanoparticles, microbes are utilized for the conversion of metal ions to nano sized particles. Platinum nanoparticles (PtNPs) exhibit intrinsic antimicrobial, anticancer, and antioxidant activities. Thus they are extensively used for biomedical applications. Bacteria like Acinetobacter calcoaceticus, Calothrix cyanobacteria , fungi such as F. oxysporum and Neurospora crassa , and algae like Padina gymnospora and Plectonema boryanum were reported as reducing agent and stabilizing agent for the microbial synthesis of Pt NPs. Size of the bacteria based synthesized Pt NPs (2 to 3.5nm) were lower when comparing to fungi (2 to 100nm) and algae (25 to 300nm) based synthesized nanoparticles. Pt NPs with cuboidal, hexagon, triangle, quasi spherical, octahedral, and spherical shapes were reported. Variations in shape were due to different kind of microbe used and other conditions of synthesis. The microbial synthesized Pt NPs exhibited excellent antibacterial activity.