Sensitive and selective determination of riboflavin (vitamin B2) based on boron-doped diamond electrode

Abstract

In this paper, we present electrochemical behavior and determination of riboflavin in pharmaceutical tablets by square wave voltammetry using unmodified boron-doped diamond electrode. In Britton–Robinson buffer solution at pH 2, by employing cyclic voltammetry it is demonstrated that riboflavin undergoes a diffusion-controlled quasi-reversible electron transfer reaction. The experimental parameters, such as pH of the supporting electrolyte, square wave voltammetry parameters, influence of most common interferences, were examined. Under optimized experimental conditions in Britton–Robinson buffer solution at pH 2, linear calibration curves were obtained in the wide range from 0.02 to 35 µM, with the capability of detection of 0.0037 µM. Repeatability of ten measurements was calculated at four concentrations from linear range and all values were <1.8 %. Proposed method was successfully applied for the determination of the total vitamin content in pharmaceutical preparations and urine samples. The developed approach could be beneficial for the quantification of vitamin in drugs using boron-doped diamond electrode as up-to-date electrochemical sensor and could represent inexpensive analytical alternative to separation methods.