Formation of Au/Pd Alloy Nanoparticles on TMV

A gold-palladium (AuPd) solid solution alloy was successfully deposited on the genetically engineered tobacco mosaic virus (TMV1Cys) by the biosorption of Au(III) and Pd(II) precursors and the reduction of the Au(III) and Pd(II) to their respective metals or metal alloy. The resulting morphologies of alloy nanoparticles deposited on the TMV1Cys were observed with transmission electron microscopy (TEM), and the AuPd alloy formation was supported with surface plasmon resonance (SPR) and selected area electron diffraction (SAED). In addition, selected alloy nanoparticles on the TMV1Cys were analyzed further with electron energy loss spectroscopy (EELS) to confirm the presence of gold and palladium. Our result implies that biotemplated metal mineralization is a potentially useful methodology to prepare alloy nanoparticles.