We report on the synthesis of gold nanoparticles (Au-NP) stabilized by a layer of mercapto and/or hydroxyl bola palmitic acid-tetrabutyl ammonium salts (TBAOH) which form nanosomes in water. Mixing both bola fatty acids in water in various proportions allowed to tune the nanoparticle diameter from 1 to 10 nm using NaBH4 as a reductor. Those nanoparticles could be phase transferred to dichloromethane by adding a more hydrophobic counter-ion than TBAOH, its derivative with octyl chains (TOAOH). Finally, we used those Au-NP to formulate emulsions, the stability of which was followed as a function of particle size and time. The emulsions were stable but creamed after several hours. We conclude that bola fatty acid nanosomes are then good candidates to synthesize gold nanoparticles dispersed either in water, organic solvents and emulsions. Crown Copyright (C) 2009 Published by Elsevier Inc. All rights reserved