Direct synthesis of amphiphilic polyvinylpyrrolidone-capped gold nanoparticles in chloroform

Abstract In this paper, we report the direct synthesis of amphiphilic gold nanoparticles in chloroform in the presence of polyvinylpyrrolidone (PVP), which acts both as a capping and size-controlling agent. Unlike in previous works reporting the preparation of PVP-capped nanoparticles in highly polar solvents, the synthesis in chloroform allows obtaining amphiphilic nanoparticles without the need for additional treatment. Prepared gold nanoparticles can either spontaneously transfer into water or can be readily dissolved in the variety of different solvents yielding stable non-aggregated colloidal solutions. The amphiphilic nature of obtained nanoparticles widens their potential for the implementation in applications where the presence of water is undesirable or is to be avoided.