Design and Synthesis of Dual Thermoresponsive and Antifouling Hybrid Polymer/Gold Nanoparticles

A series of thermosensitive copoly(oligoethylene oxide) acrylates with narrow polydispersities were prepared by the copolymerization of oligo(ethylene oxide) acrylate and di(ethylene oxide) ethyl ether acrylate using reversible addition-fragmentation chain transfer polymerization (RAFT). These copolymers exhibit tunable LCST behavior over the range of 15-90 degrees C dependent on their monomer Compositions. Subsequently, these copolymers were grafted onto gold nanoparticle (GNP) surfaces yielding thermosensitive gold nanoparticles. The thermoresponsive properties of these hybrid GNPs/poly(OEG-A-co-DEG-A) nanoparticles were evaluated in solution using dynamic light scattering and UV-vis spectroscopy. In addition, the susceptibility of these GNPs to protein fouling was assessed by a Bradford's assay and found to be significantly reduced by the copolymer stabilizing layer. We also demonstrate, in a unique one-pot assembly process, the synthesis of a hybrid nanoparticle that shows dual temperature responsiveness. These hybrid nanoparticles open new applications in biotechnology and medicine.