ELECTROCHEMICAL BEHAVIOR AND SIMULTANEOUS DETERMINATION OF VITAMIN B2, B6, AND C AT ELECTROCHEMICALLY PRETREATED GLASSY CARBON ELECTRODE

An electrochemically pretreated glassy carbon electrode (PGCE) was achieved by anodic oxidation at 1.8V and following potential cycling in the potential range from -0.8 to +1.0 V. The resulting PGCE gave well-defined redox peaks with Epa= -0.073 V, Epc = 0.044 V. The PGCE showed good activity in improving the electrochemical responses of some watersoluble Vitamins, such as Vitamin (VB2), Vitamin (VB6) and Vitamin (VC). VB2, VB6 could be adsorbed at PGCE and VC proceeded with an electrocatalytic process. The electrochemical behavior of VB6 at PGCE depended on the potential scanning method and the pretreatment process of the electrode. The PGCE was rather stable and can be used to simultaneously determine these vitamins in multivitamin tablets.