The Determination of Glycogen in Liver and Muscle by Use of Anthrone Reagent* by Nicholas

In currently used methods for the determination of glycogen, tissue is extracted either by boiling with 30 per cent potassium hydroxide solution (KOH) or by homogenization with trichloroacetic acid solution (TCA). The glycogen is precipitated from the extract by alcohol and determined either by copper reduction after separation by centrifugation, acid hydrolysis, and neutralization (l-3) or by direct treatment of the precipitated glycogen with anthrone reagent (4-6). An alternative procedure is to destroy alkali-labile carbohydrate by boiling with KOH and then determine the glycogen in the alkali-treated mixture with anthrone reagent (5, 7). Previously, we have reported that a method based upon the use of anthrone reagent gave results of a high degree of specificity and precision (8). This method is a modification of procedures for the determination of dextran (9) and biood sugar (10). In this paper we are reporting in detail our anthrone-adapted method, with critical studies of procedures based upon extraction of tissues with 30 per cent KOH and with 5 per cent TCA.