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%.
Keywords: Anodic peak current, Composite carbon paste electrode, Cyclic voltammetry, Differential pulse voltammetry, Dopamine, Riboflavin.
