An enzymic method for measurement of glycogen

Abstract

An enzymic method for measuring glycogen has been described in detail. Glycogen plus inorganic phosphate and TPN+ are converted in one analytical step to 6-P-gluconolactone and TPNH. The TPNH is measured by its fluorescence or ultraviolet absorption. The method uses commercially available enzymes: phosphorylase a, P-glucomutase, and glucose-6-P dehydrogenase. It takes advantage of the fact that most phosphorylase preparations contain sufficient transglucosylase and glucosidase to permit complete degradation of glycogen. The specificity is such that whole tissue can be analyzed directly. The sensitivity is sufficient to measure 0.05 μg of glycogen with precision.