Patent ID: 8697129
Filing Date: 2014-04-15
Classification: A61K,A61P,B01J,B82Y,G01N

Abstract:
1. A method of producing stable colloidal gold nanoparticles with surface modification comprising the steps of: a) preparing a stable colloidal gold nanoparticle preparation of bare gold nanoparticles in a colloidal suspension liquid by a top-down nanofabrication method using bulk gold as a source material; b) determining a footprint size of at least one ligand bound to said nanoparticles, said at least one ligand having at least one functional group which binds to said gold nanoparticles, wherein said footprint size is determined by at least one of measuring an increase in hydrodynamic diameter as determined by dynamic light scattering during ligand conjugation of said ligand to said nanoparticles, measuring absorbance at 520 nanometers during ligand conjugation of said ligand to said nanoparticles in the presence of 1% by weight of NaCl, by fluorescence spectrum analysis of conjugation of a fluorescently labeled ligand to said nanoparticles, by reference to literature values, or by a mixture of these methods, and then determining an amount of said at least one ligand required to form a complete monolayer of bound ligand on said nanoparticles based on said determined footprint size; c) performing surface modification of said bare gold nanoparticles by adding to said colloidal bare gold nanoparticles an amount of said at least one ligand having at least one functional group which binds to said gold nanoparticles, wherein the total amount of said ligand added is no more than three times the amount required to provide a complete monolayer of bound ligand to the total of said bare gold nanoparticles based on said determined footprint of said ligand bound on said nanoparticles, and binding at least a portion of said amount of said ligand to said gold nanoparticles in an amount up to a complete monolayer of said ligand on said nanoparticles.