Water-Soluble Polymer-Grafted Platinum Nanoparticles for the Subsequent Binding of Enzymes. Synthesis and SANS
Résumé
Functionalized platinum nanoparticles (PtNPs) possess catalytic properties towards H202 oxidation, which are of great interest for the elaboration of electrochemical biosensors. To improve the understanding of phenomena involved in such systems, we designed platinum-polymer-enzyme model nanostructures according to a bottom-up approach. These structures have been elaborated from elementary building units based on polymer-grafted PtNPs obtained from surface initiated-atom transfer radical polymerization. This paper describes the polymerization of ter-butyl methacrylate from PtNPs and its subsequent hydrolysis to obtain a water-soluble corona, followed by an activated ester modification to introduce an enzyme (glucose oxidase). The structure of the objects, the molecular weight and the grafting density of the polymer chains were principally elucidated by small angle neutron scattering (SANS). After the grafting of the enzyme, the final hybrid structures were characterized by both microscopy and SANS to attest for the covalent grafting of the enzyme. Composition and enzyme activity of the nanohybrid objects, have also been determined by UV spectroscopy.