Stable Poly(methacrylic acid) Brush Decorated Silica Nano-Particles by ARGET ATRP for Bioconjugation Marcello Iacono Andreas Heise 10779/rcsi.10991372.v1 https://repository.rcsi.com/articles/journal_contribution/Stable_Poly_methacrylic_acid_Brush_Decorated_Silica_Nano-Particles_by_ARGET_ATRP_for_Bioconjugation/10991372 <p>The synthesis of polymer brush decorated silica nano-particles is demonstrated by activator regeneration by electron transfer atom transfer radical polymerization (ARGET ATRP) grafting of poly(tert-butyl methacrylate). ATRP initiator decorated silica nano-particles were obtained using a novel trimethylsiloxane derivatised ATRP initiator obtained by click chemistry. Comparison of de-grafted polymers with polymer obtained from a sacrificial initiator demonstrated good agreement up to 55% monomer conversion. Subsequent mild deprotection of the tert-butyl ester groups using phosphoric acid yielded highly colloidal and pH stable hydrophilic nano-particles comprising approximately 50% methacrylic acid groups. The successful bio-conjugation was achieved by immobilization of Horseradish Peroxidase to the polymer brush decorated nano-particles and the enzyme activity demonstrated in a conversion of o-phenylene diamine dihydrochloride assay.</p> 2019-11-23 11:49:36 Silica Nano-Particles Polymer Brushes ARGET ATRP Poly(methacrylic acid) Bio-Conjugation Enzyme Immobilization