Facile synthesis and colloidal stabilization of metal nanoparticles in aqueous amphiphilic block copolymer solutions

The synthesis of gold nanoparticles with diameter of ∼10 nm was achieved at ambient conditions by simple mixing an aqueous hydrogen tetrachloroaureate (III) hydrate solution with an aqueous amphiphilic block copolymers. It was found that the block copolymer molecular weight, PEO and PPO block lengths controlled the reaction activity of the block copolymer with AuCl ₄ ^- ions. The synthesis method presented was environmentally gentle since it involved water and polymers that were not only non-toxic but also approved for pharmaceutical use. The results show that the block copolymer molecular characteristics and the relative concentration of the reactants allowed for tunability of particle properties.