Assay of erythrocyte glucose-6-phosphate dehydrogenase on the GEMSAEC analyser

A procedure for the assay of glucose-6-phosphate dehydrogenase (EC 1.1.1.49) in erythrocytes on the GEMSAEC centrifugal analyzer using a modification of Beutler's procedure is described. Glucose-6-phosphate dehydrogenase activity is corrected for the contributing activity of 6-phosphogluconate dehydrogenase (EC 1.1.1.44) by using a two-cuvet system in which the activity of the sample incubated with 6-phosphogluconic acid is subtracted from the activity produced in the presence of the combined substrates, glucose-6-phosphate and 6-phosphogluconic acid. An overlay program on the GEMSAEC computer for calculation of results, and the use of a yeast glucose-6-phosphate dehydrogenase control which is stable frozen in dilute solution are discussed.