Fast determination of glutathione by capillary electrophoresis with fluorescence detection using β-cyclodextrin as modifier

A rapid analytical method was developed for the quantitative determination of glutathione (GSH) using capillary electrophoresis and fluorescence detection. A fluorescence derivatization reagent, naphthalene-2,3-dicarboxaldehyde (NDA) was successfully applied to label GSH. The optimal derivatization reaction was performed with 5.0 mM NDA, 20 mM borate buffer (pH 9.2) with the reaction time of 4 min at room temperature. The capillary electrophoresis analysis of GSH could be achieved in less than 120 s using 10 mM sodium tetraborate (pH 9.2) containing 2.5 mM β-cyclodextrin (β-CD) as the running buffer, and the detection limit of 2.5 × 10−9 M (S/N = 3) was obtained. This method was successfully applied to analyze the content of GSH in tobacco BY-2 cells.