Patent ID: 8734844

Claim:
A method of synthesizing ligand-conjugated gold nanoparticles (AuNPs), comprising: providing amine-modified silica particles; providing a solution comprising HAuCl 4 ; suspending the amine-modified silica particles in the solution comprising the HAuCl 4 ; producing silica particles-NH 3 + AuCl 4 − complexes by allowing Au 3+ ions in the solution to be adsorbed and/or immobilized onto the surface of the amine-modified silica particles, wherein the solution has no mesoporous silica nanoparticles (MSN) present; exposing the silica particles-NH 3 + AuCl 4 − complexes to radiation to reduce the Au 3+ ions and obtain bare gold nanoparticles (AuNPs) adsorbed and/or immobilized onto the surface of the amine-modified silica particles, wherein the bare AuNPs are without organic surface modifications; and reacting a ligand with the bare AuNPs adsorbed and/or immobilized onto the surface of the amine-modified silica particles under sonication to desorb and modify the bare AuNPs and thereby synthesizing the ligand-conjugated gold nanoparticles.