Biological synthesis of platinum nanoparticles using Diopyros kaki leaf extract.

The leaf extract of Diopyros kaki was used as a reducing agent in the ecofriendly extracellular synthesis of platinum nanoparticles from an aqueous H(2)PtCl(6).6H(2)O solution. A greater than 90% conversion of platinum ions to nanoparticles was achieved with a reaction temperature of 95 degrees C and a leaf broth concentration of >10%. A variety of methods was used to characterize the platinum nanoparticles synthesized: inductively coupled plasma spectrometry, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and Fourier-transform infrared spectroscopy (FTIR). The average particle size ranged from 2 to 12 nm depending on the reaction temperature and concentrations of the leaf broth and PtCl(6) (2-). FTIR analysis suggests that platinum nanoparticle synthesis using Diopyros kaki is not an enzyme-mediated process. This is the first report of platinum nanoparticle synthesis using a plant extract.