Biogenic Approach using Sheep Milk for the Synthesis of Platinum Nanoparticles: The Role of Milk Protein in Platinum Reduction and Stabilization

Bio-directed synthesis of nanoparticles is an interesting field of rapid advancement for biologists,chemists and materials scientists, especially in light of efforts to find out green methods of inorganicmaterial synthesis. In the present study, green synthesis of platinum nanoparticles (PtNPs) using sheepmilk is reported for the first time. By adjusting the concentrations of chloroplatinic acid (H2PtCl6) andmilk in aqueous solutions, spherical PtNPs were obtained at room temperature. The nanoparticlesobtained were characterized by UV-Vis spectroscopy, dynamic light scattering (DLS), high-resolutionTransmission Electron Microscopy (TEM) and X-Ray diffraction (XRD). The spherical particles obtainedhave an average size 9.0 nm as shown by XRD pattern and TEM analysis. Fourier Transform Infra-Red(FTIR) measurements were carried out to identify the possible biomolecules responsible for capping andefficient stabilization of the PtNPs synthesized by milk. The carboxylic acid group libration and amide Iand II bands revealed the binding of protein with platinum surface through the amine group rather thanthe carboxyl group. Among a wide variety of biological resources which are introduced for reducing Ptions into PtNPs, green approaches like using sheep milk have outstanding benefits for synthesizebiological metal nanoparticles due to their eco-friendly phenomenon and very less amounts ofcytotoxicity. PtNPs green synthesized in this study are potential candidates to use in drug discovery andgene transfer technologies.