This note describes a determination method for water-soluble vitamins using an electrochemical detector （ECD）.
Analysis of water-soluble vitamins are generally performed using UV detection coupled with reversed-phase HPLC. However, sensitive determination of some vitamins [e.g. biotin (Vitamin B7)] with HPLC-UV system is difficult, because their response to UV detector is very weak. In such case, ECD is a powerful alternative to UV detector. Biotin can be detected with high sensitivity as well as cyanocobalamin because both are electrochemically reactive species.
ED703 pulse is an ECD equipped with boron-doped diamond electrode. The diamond working electrode offers stable response, low background current and wide potential window. ED703 pulse is very useful to quantify various compounds.