Stabilization of coated inorganic nanoparticles by amphiphilic copolymers in aqueous media. Dissipative particle dynamics study

Hybrid organic-inorganic nanoparticles find a number of applications in medicine and in various nanotechnologies, and they have been amply studied both by experimentalists and theoreticians. Their safe application assumes the design and development of stable aqueous dispersions. In this paper, we report on computer simulations aimed at the elucidation of our recent experimental results. By dissipative particle dynamics, we emulated aqueous mixtures of two different species: (i) associates of heavy inorganic nanoparticles modified by relatively short hydrophobic chains tethered to their surface and (ii) amphiphilic copolymer chains. The simulations show that coated inorganic nanoparticles can be stabilized by block copolymers and that a relatively modest excess of copolymer chains with respect to the number of nanoparticles is sufficient to stabilize the aqueous dispersions.