Patent ID: 8741384

Claim:
A method of synthesizing branched gold nanoparticles by seed-mediated growth, comprising the steps of: a) providing a first aqueous solution of gold nanoparticle spherical seeds; and b) subjecting the gold nanoparticle spherical seeds to a growth treatment, characterized in that it comprises: b 1 ) treating the first aqueous solution of gold nanoparticle spherical seeds with a second aqueous solution comprising hydroxylamine or a salt thereof as a reducing agent and 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) as an agent that directs the shape of the said nanoparticles; and b 2 ) adding a third aqueous solution comprising aurate ions to the mixture of the first aqueous solution and the second aqueous solution as obtained in step b1), thereby obtaining branched gold nanoparticles by the controlled growth of branches on the surface of the gold nanoparticle spherical seeds.