title: Evaluation of the oxidase like activity of nanoceria and its application in colorimetric assays.
abstract: Nanomaterial-based enzyme mimics have attracted considerable interest in chemical analysis as alternative catalysts to natural enzymes. However, the conditions in which such particles can replace biological catalysts and their selectivity and reactivity profiles are not well defined. This work explored the oxidase like properties of nanoceria particles in the development of colorimetric assays for the detection of dopamine and catechol. Selectivity of the system with respect to several phenolic compounds, the effect of interferences and real sample analysis are discussed. The conditions of use such as buffer composition, selectivity, pH, reaction time and particle type are defined. Detection limits of 1.5 and 0.2μM were obtained with nanoceria for dopamine and catechol. The same assay could be used as a general sensing platform for the detection of other phenolics. However, the sensitivity of the method varies significantly with the particle type, buffer composition, pH and with the structure of the phenolic compound. The results demonstrate that nanoceria particles can be used for the development of cost effective and sensitive methods for the detection of these compounds. However, the selection of the particle system and experimental conditions is critical for achieving high sensitivity. Recommendations are provided on the selection of the particle system and reaction conditions to maximize the oxidase like activity of nanoceria.
authors.affiliation: Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, USA; Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology (CIIT), Lahore, Pakistan.
authors.forename: Akhtar
authors.initials: A
authors.lastname: Hayat
authors.affiliation: Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, USA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Cunningham
authors.affiliation: Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, USA.
authors.forename: Gonca
authors.initials: G
authors.lastname: Bulbul
authors.affiliation: Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, NY, USA. Electronic address: eandrees@clarkson.edu.
authors.forename: Silvana
authors.initials: S
authors.lastname: Andreescu
mesh_terms: D040761:Biomimetic Materials / Q000737:chemistry*; D002021:Buffers; D002396:Catechols / Q000032:analysis / Q000097:blood*; D002563:Cerium / Q000737:chemistry*; D003124:Colorimetry / Q000379:methods; D004298:Dopamine / Q000032:analysis / Q000097:blood*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D057230:Limit of Detection; D009994:Osmolar Concentration; D010088:Oxidoreductases / Q000737:chemistry*
chemical_list: D002021:Buffers; D002396:Catechols; D002563:Cerium; C030583:ceric oxide; D010088:Oxidoreductases; C034221:catechol; D004298:Dopamine
keywords: Catechol; Colorimetric assay; Dopamine; Nanoceria particles; Oxidase mimic