Affinity electrophoresis of human serum alkaline phosphatase isoenzymes in agarose gel containing lectin.

Separation of alkaline phosphatase isoenzymes using affinity electrophoresis in agarose gel containing lectin is described. The bone and biliary isoenzymes precipitate during electrophoresis and are clearly separated from the liver isoenzyme. The liver, intestinal and placental alkaline phosphatases are essentially not affected by the lectin. The migration distances of the precipitating bone and biliary fractions vary with their alkaline phosphatase activity. The bone isoenzyme is more heterogeneous than the biliary isoenzyme with respect to interaction with lectin forming both insoluble and soluble complexes. Affinity electrophoresis in agarose gel containing lectin can be used for quantitation by densitometry of liver and bone isoenzymes in sera containing only these two fractions but must be combined with conventional electrophoresis, preferably in agar gel, if biliary, intestinal, or placental isoenzymes are also present.