Application of Poly (3-methylthiophene) Modified Glassy Carbon Electrode as Riboflavin Sensor

Abstract

The electrochemical behavior of riboflavin (VB2) at a glassy carbon electrode modified with poly (3-methylthiophene) (P3MT) was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The poly (3-methylthiophene) modified glassy carbon electrode (P3MT/GCE) can greatly enhance the peak currents and the detection sensitivity of VB2 under optimal conditions. Cyclic measurements showed that the electron transfer number, n, was calculated to be 2 and the diffusivity (D0) was 2.6×10-5 cm2 s-1. The quantitative analysis of VB2 was made by the DPV method, the relative deviation was 1.5% for 7 successive determinations at 0.1 μmol L-1 VB2 in 0.1 mol L-1 pH 4.0 phosphate buffer solution (PBS), and the peak current on the modified electrode was linear over a range from 1.0× 10-7 to 2.0× 10-4 mol L-1 riboflavin, with the detection limit of 5.0× l0-8 mol L-1(S/N=3).