Decomposition of Toxic Environmental Contaminants by Recyclable Catalytic, Superparamagnetic Nanoparticles

Abstract

Catalytic hydrolysis of toxic organic environmental contaminants such as organophosphates by inorganic nanocrystals or polymeric latexes is emerging as a promising alternative to other remediation approaches. We have recently developed a novel catalytic medium, an inorganic nanoparticle surface-modified by a reactive polymer that can be considered a hybrid between nanocrystals and latexes. In the present work, a model warfare agent, diisopropyl fluorophosphate, is hydrolyzed catalytically in aqueous media by suspensions of magnetite (Fe3O4) nanoparticles modified with poly(1-vinylimidazole-co-acrolein oxime-co-acrylic acid) that acts in an enzyme-like fashion. The oxime- and imidazole-modified magnetite particle serves as a nanosized particulate carrier with nucleophilic groups immobilized on its surface. The oxime-modified magnetite nanoparticles are colloidally stable within a wide pH range and are readily recovered for reuse from the aqueous milieu by high-gradient magnetic separation methods with no l...