We present a process for the phase-transfer of gold nanoparticles from an aqueous to an organic medium with normal alkanethiols. This method can be applied not only to large nanospheres (d similar to 100 nm) but also to anisotropic nanoparticles like nanorods and nanoplates. It allows the comparison of the nanoparticle optical properties when they are dispersed in both aqueous and organic media. (C) 2011 Elsevier Inc. All rights reserved.