title: Manganese dioxide-modified carbon paste electrode for voltammetric determination of riboflavin.
abstract: A carbon paste electrode bulk was modified with MnO2and investigated for use as an electrochemical sensor for riboflavin (vitamin B2) using differential pulse voltammetry (DPV). Riboflavin displays a well expressed oxidation peak at -0.15 V (versus Ag/AgCl) in solutions with a pH value of 2. Effects of pH value, pulse amplitude and pulse time were optimized by employing DPV. The signals obtained are linearly related to the concentrations of riboflavin in the range from 0.02 to 9 μM. Other features include a 15 nM detection limit, and good reproducibility (±3 %) and repeatability (±2 %). Interferences by common compounds were tested, and the method was successfully applied to the determination of riboflavin in pharmaceutical formulations where is gave recoveries in the range from 95 to 97 %. Graphical abstractManganese(IV) oxide was used as a modifier for the carbon paste electrode (MnO2/CPE) for improving its performance toward riboflavin oxidation. Cyclic voltammetry and differential voltammetry were used for characterization and determination of riboflavin, respectively.
authors.affiliation: Institute of Chemistry, Analytical Chemistry, Karl-Franzens University, 8010 Graz, Austria.
authors.forename: Eda
authors.initials: E
authors.lastname: Mehmeti
authors.affiliation: Department of Analytical Chemistry, Innovation Center of the Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, 11000 Serbia.
authors.forename: Dalibor M
authors.initials: DM
authors.lastname: Stanković
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok, 10330 Thailand.
authors.forename: Sudkate
authors.initials: S
authors.lastname: Chaiyo
authors.affiliation: Institute of Analytical Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37 Bratislava, Slovak Republic.
authors.forename: Ľubomir
authors.initials: Ľ
authors.lastname: Švorc
authors.affiliation: Institute of Chemistry, Analytical Chemistry, Karl-Franzens University, 8010 Graz, Austria.
authors.forename: Kurt
authors.initials: K
authors.lastname: Kalcher
keywords: Cyclic voltammetry; Differential pulse voltammetry; Electrooxidation; Vitamin B2