Preparation of small silver, gold and copper nanoparticles which disperse in both polar and non-polar solvents

We report a new route to colloids of silver, gold and copper nanoparticles which disperse well in an unusually broad range of solvents from water to toluene. The broad dispersibility of the particles is a result of a novel polyethylene glycol (PEG) based stabiliser containing approximately 16 repeat units. The capping agent binds strongly to the surface of the particles providing a well coated particle in the case of gold and silver particles demonstrating a significant change in melting transition (T-m) of the polymer coating.