Cellulose Acetate Electrophoresis of Alkaline Phosphatase Isoenzymes in Human Serum and Tissue

Abstract

Abstract We describe a new electrophoretic method for the characterization of human serum and tissue alkaline phosphatases on cellulose acetate plates. Enzymes are localized fluorometrically with the substrate α-naphthol AS-MX phosphate or colorimetrically by coupling the reaction product with Fast Blue RR. Both localization techniques are sensitive enough to demonstrate isoenzyme patterns in micro-scale samples of normal sera. Our electrophoretic studies indicate that sera of children and adults normally contain isoenzymes originating from both liver and bone. The high sensitivity of the method allows the use of normal sera as markers rather than tissue extracts, and isoenzyme patterns may be visually assessed after heat inactivation and chemical inhibition. The method is suitable for the electrophoretic fractionation of alkaline phosphatase in large numbers of sera, with equipment and technique familiar to many laboratories.