Better separation of hepatic and skeletal alkaline phosphatase isoenzymes

Abstract

Electrophoresis is commonly used to separate alkaline phosphatase isoenzymes. In many electrophoretic techniques, isoenzymes originating from liver and bone are not well distinguished. Techniques to improve the separation of hepatic and skeletal isoenzymes were studied using sera from patients in the last trimester of pregnancy and patients with hepatic or intestinal disease as well as neonates and normal subjects. Alterations were made to the method stipulated by the manufacturer which improved the separation of hepatic and skeletal alkaline phosphatase isoenzymes with the Corning ACI Cassette agarose gel electrophoretic system. The best separation of hepatic and skeletal isoenzymes, without loss of definition, was obtained by: increasing running time from 25 to 45 min, decreasing buffer molarity from 50 to 33 mmol/l (6.85 g sodium barbital per litre of distilled water) and increasing buffer pH from 8.6 to 10.0 (by adding 6 mol/l NaoH and checking with a pH meter).