Gold-Coated Cobalt Ferrite Nanoparticles via Methionine-Induced\nReduction

Abstract

Functionalized\nsuperparamagnetic nanoparticles (Nps) are among\nthe most investigated research topics. In this study, we present an\nefficient protocol for gold deposition onto the surface of cobalt\nferrite (CoFe₂O₄) Nps by a simple one-pot reduction\nof AuCl₄^– ions with amino acid methionine,\nwhich, in turn, produces the biocompatible stabilizing shell. In contrast\nto previously reported gold deposition recipes, the one suggested\nherein is distinguished by the simplicity and prevention of monogold\ncrystallite nucleation and growth in the deposition solution bulk.\nTo demonstrate the preferential deposition of gold onto the surface\nof ferrite Nps, high-resolution transmission electron microscopy (HRTEM),\nenergy-dispersive X-ray spectroscopy (EDX), inductively coupled plasma\nmass spectrometry, and Fourrier-transformed infrared spectroscopy\n(FTIR) investigations have been performed. The innovative gold deposition\nmethod is expected to open new horizons for the design of biocompatible\nwater dispersible gold/methionine-functionalized ferrite nanoparticles\nby a simply controllable way.