Synthesis and characterization of bimetallic noble metal nanoparticles for biomedical applications

Abstract

We report herein a facile approach to synthesize processable bimetallic nanoparticles (Pd-Au/AuPd/Ag-Au/Au-Ag) decorated Prussian blue nanocomposite (PB-AgNP). The presence of cyclohexanone/formaldehyde facilitates the formation of functional bimetallic nanoparticles from 3-aminopropyltrimethoxysilane (3-APTMS) capped desired ratio of hetero noble metal ions. The use of 3-APTMS and cyclohexanone also enables the synthesis of polycrystalline Prussian blue nanoparticles (PBNPs). As synthesized PBNPs, Pd-Au/Au-Pd/Ag-Au/Au-Ag enable the formation of nano-structured composites displaying better catalytic activity than that recorded with natural enzyme. The nanomaterials have been characterized by Uv-Vis, FT-IR and Transmission Electron Microscopy (TEM) with following major findings: (1) 3-APTMS capped noble metal ions in the presence of suitable organic reducing agents i.e.; 3 glycidoxypropyltrimethoxysilane (GPTMS), cyclohexanone and formaldehyde; are converted into respective nanoparticles under ambient conditions, (2) the time course of synthesis and dispersibility of the nanoparticles are found as a function of organic reducing agents, (3) the use of formaldehyde and cyclohexanone in place of GPTMS with 3-APTMS outclasses the other two in imparting better stability of amphiphilic nanoparticles with reduced silanol content, (4) simultaneous synthesis of bimetallic nanoparticles under desired ratio of palladium/gold and silver/ gold cations are recorded, (5) the nanoparticles made from the use of 3-APTMS and cyclohexanone enable the formation of homogeneous nanocomposite with PBNP as peroxidase mimetic representing potential substitute of peroxidase enzyme. The peroxidase mimetic ability has been found to vary as a function of 3-APTMS concentration revealing the potential role of functional metal nanoparticles in bioanalytical applications. © Copyright 2016 Materials Research Society.