Method for manufacturing nanoparticles comprising a metallic core coated with a layer of polymer material comprising the following steps:
- a) preparing a water-in-oil emulsion comprising droplets of an aqueous phase, dispersed in an organic phase,
- b) adding nanoparticles comprising a metallic core coated with a shell of carbonaceous material, whereby nanoparticles trapped in the droplets are obtained,
- c) adding precursor monomers of the polymer material, and
- d) adding a polymerisation initiator,
- adding the precursor monomers of the polymer material and the polymerisation initiator resulting in polymerisation of the monomers, whereby nanoparticles coated with a layer of polymer material, dispersed in the organic phase, are obtained.