Chemoselective Immobilization of Gold Nanoparticles\nonto Self-Assembled Monolayers

Abstract

This Letter describes a general method for the immobilization of gold nanoparticles onto solid supports.\nKetone-decorated gold colloids are covalently attached to self-assembled monolayers (SAMs) presenting\naminooxy groups on a gold surface. The oxime formed by the chemoselective ligation is stable on the film\nas shown by the cyclic voltammetry of ferrocenecarboxaldehyde immobilized onto aminooxy SAMs. The\ncolloids are characterized by infrared spectroscopy, transmission electron microscopy, and ¹H NMR. Tapping\nmode atomic force microscopy shows that the gold nanoparticles are uniformly distributed on the surface\nwith an average particle diameter of 5.5 nm.