Separation of reduced and oxidized glutathione in a pharmaceutical preparation by ion-interaction reversed-phase HPLC

A new method is presented for the simultaneous determination of reduced and oxidized glutathione by ion-interaction reversed-phase HPLC with octylamine orthophosphate as the interaction reagent, 5-microns Spherisorb ODS-2 as the stationary phase and UV detection at 230 nm. Lower limits of detection of 2.50 micrograms ml-1 have been achieved for both the oxidized and the reduced forms. The method has been applied in the analysis of a commercial pharmaceutical preparation.