title: Attaching DNA to nanoceria: regulating oxidase activity and fluorescence quenching.
abstract: Cerium oxide nanoparticles (nanoceria) have recently emerged as a nanozyme with oxidase activity. In this work, we present a few important interfacial properties of nanoceria. First, the surface charge of nanoceria can be controlled not only by adjusting pH but also by adsorption of simple inorganic anions. Adsorption of phosphate and citrate gives negatively charged surface over a broad pH range. Second, nanoceria adsorbs DNA via the DNA phosphate backbone in a sequence-independent manner; DNA adsorption inhibits its oxidase activity. Other anionic polymers display much weaker inhibition effects. Adsorption of simple inorganic phosphate does not have the inhibition effect. Third, nanoceria is a quencher for many fluorophores. These discoveries provide an important understanding for further use of nanoceria in biosensor development, materials science, and nanotechnology.
authors.affiliation: Department of Chemistry and Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Rachel
authors.initials: R
authors.lastname: Pautler
authors.forename: Erin Y
authors.initials: EY
authors.lastname: Kelly
authors.forename: Po-Jung Jimmy
authors.initials: PJ
authors.lastname: Huang
authors.forename: Jing
authors.initials: J
authors.lastname: Cao
authors.forename: Biwu
authors.initials: B
authors.lastname: Liu
authors.forename: Juewen
authors.initials: J
authors.lastname: Liu
mesh_terms: D000327:Adsorption; D000818:Animals; D000838:Anions; D015374:Biosensing Techniques; D002384:Catalysis; D002563:Cerium / Q000737:chemistry; D019343:Citric Acid / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D053758:Nanoparticles / Q000737:chemistry*; D010088:Oxidoreductases / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods*; D055672:Static Electricity; D013499:Surface Properties
chemical_list: D000838:Anions; D010710:Phosphates; D019343:Citric Acid; D002563:Cerium; C030583:ceric oxide; D004247:DNA; D010088:Oxidoreductases