Methyl Orange Electropolymerized Composite Carbon Paste Electrode as a Sensitive and Selective Sensor for the Electrochemical Determination of Riboflavin

Riboflavin (RB) is a vital B group water soluble vitamin. RB is essential for all animals and humans. This essential constituent of flavoenzyme, which plays an important role in biochemical reactions, is investigated by Cyclic voltammetry (CV) and Differential pulse voltammetry (DPV) using Poly methyl orange modified composite carbon paste electrode (PMOMCCPE). RB exhibits an oxidation peak with the highest anodic current of 54.82 μA at a potential of − 0.4360 V in 0.2 M phosphate buffer solution (PBS) with a pH value of 7.5. The surface topography studies of fabricated PMOMCCPE were carried out by CV, Field emission scanning electron microscopy (FE-SEM) and Electronic impedance spectroscopy (EIS). Optimization of pH and polymer cycle was carried out, and the effect of scan rate was also studied. The anodic peak current obtained is linearly related to the variations in the concentration of RB in the range 4 to 50 μM. Other features include a detection limit of 1.67 ×10-7 M, and good reproducibility, repeatability and stability. Simultaneous determination of RB with dopamine (DA) was done and interferences by some potentially interfering compounds were tested. PMOMCCPE was successfully used for determining RB in pharmaceutical formulations which gave recoveries in the range from 96.50 to 99. 53%.