Growth kinetics of gold nanoparticles on silica/graphene surfaces for multiplex biological immunoassays

Kinetics of seed-mediated chemical growth of gold nanoparticles on silica substrates coated with a thin layer of graphene-derivative materials were studied with the ultimate goal of employing the developed graphene-nanoparticle composites in light-scattering imaging biosensor applications. The type of the surface coating and chemical conditions influence the surface number density and size of the grown nanoparticles. Importantly, when used as biosensor bases, the substrates coated with protein reduced graphene oxide have shown beneficial biological compatibility towards immobilized antibodies resulting in about 20-fold improvement in antigen capture by the antibodies tethered to the sensor surface in immunoassay performed on the multiplex photonic biosensor platform. © 2014 the Partner Organisations.