Assembly of Preformed Gold Nanoparticles onto Thermoresponsive Poly( N-isopropylacrylamide)-Based Microgels on the Basis of Au-thiol Chemistry.

The assembly of preformed gold nanoparticles ( AuNPs) onto the thermoresponsive poly( N-isopropylacrylamide) ( PNIPAM)-based microgels was achieved on the basis of the driving force of Au-thiol chemistry. The loading amount of AuNPs can be controlled by varying the ratio of AuNPs relative to PNIPAM-based microgels. The as-prepared PNIPAM/Au hybrid microgels showed well-defined reversible swelling/deswelling transition in response to temperature, which can be employed to tune the plasmonic property of hybrid microgels. As the temperature was increased, the position of localized surface plasmon resonance ( LSPR) band red-shifted to some extent mainly due to the increase in the local refractive index around AuNPs. [ABSTRACT FROM AUTHOR]