NOVEL ASSAY FOR GLUTATHIONE-REDUCTASE ACTIVITY BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH ELECTROCHEMICAL DETECTION

A new method was devised for the direct measurement of glutathione red uctase activity in crude tissue samples using high-performance liquid chromatography and electrochemical detection with a mercury/gold elect rode. This assay depends on the high sensitivity of the electrode to d etect SH groups produced from a substrate, oxidized glutathione, the i nterference of which can be excluded by setting the oxidation voltage as low as 100 mV. The sensitivity was high enough to detect the activi ty in crude samples containing less than 1 mu g of protein. This metho d proved to be sensitive and simple for the measurement of this biolog ically important reductant activity without the need for a further pur ification procedure. (C) 1998 Elsevier Science B.V.