Gold nanorods protected by hexadecyltrimethylammonium bromide were treated by an organosilane, aminopropyltriethoxysilane (APS) or vinyltrimethoxysilane (VS) in the presence of mercaptopropyltrimethoxysilane (MPS) serving as a binder. After the APS- or VS-treatment, a shell about 4 nm thick surrounding the nanorods was found by means of transmission electron microscopy. Its formation enabled the nanorods to be dispersed in polar media (ethanol, methanol, acetone and acetonitrile/water mixtures). (C) Koninklijke Brill NV, Leiden, 2009