Detection of menadione sodium bisulfite (vitamin K3) by reversed-phase high performance liquid chromatography with series dual-electrode amperometric detector

A reversed-phase high-performance liquid chromatography with series dual glassy carbon electrodes for the amperometric detection of water-soluble menadione is described. The complex post-column derivatization reaction and the high background currents were avoided. The menadione sodium bisulfite was reduced at −0.3 V vs. SCE at the upstream (generator) electrode and oxidized at +0.2 V vs. SCE at the downstream (collector) electrode. The mobile phase was 0.2 mol l−1 HAcNaAc aqueous buffer (pH 5.50) and 40% (v/v) methanol. The linear response was in the range of 35 ng to 15 μg, with a detection limit of 15 ng (SN = 3). The correlation coefficient was 0.9997 (n = 6). The electrochemical detection with series dual electrodes has a higher selectivity for menadione (vitamin K3) compound than with UV detection.