Voltammetric determination of riboflavin based on electrocatalytic oxidation at zeolite-modified carbon paste electrodes

Carbon-paste electrode modified with Co2+-Y zeolite was used in voltammetric determination of riboflavin. Maximum anodic voltammetric current, due to the redox behavior of Co2+ ions, was observed in 0.1 mol L−1 KNO3 with pH 5. The modified electrode showed a catalytic behavior in electro-oxidation of riboflavin, lowering the over-potential of the reaction by ∼200 mV. The effect of several parameters such as pH and concentration of the supporting electrolyte was investigated. The cyclic voltammetric response of the electrode to riboflavin was linear in the range of 1.7 to 34 μmol L−1 with a detection limit of 0.71 μmol L−1.