The invention relates to a method for preparing a solution of micelles in an organic medium, which micelles comprise nanoparticles stabilized by a shell of at least one polymer having a terminal anchoring group which exhibits a high affinity to the surface of the nanoparticles. In a preferred embodiment, said method comprises at least the following steps: i) providing an aqueous solution/dispersion of nanoparticles, in particular metal or metal oxide nanoparticles, stabilized by a shell of a first stabilizing agent; ii) optionally displacing the molecules of the first stabilizing agent by molecules of a second stabilizing agent; iii) transferring the stabilized nanoparticles obtained in step i) or ii) into a solution/dispersion of anchoring group-terminated polymer in an unpolar organic solvent; iv) displacing the molecules of the first or second stabilizing agent by anchoring group-terminated polymer molecules having a higher affinity to the nanoparticles than the molecules of the first or second stabilizing
