Quantitative determination of high molecular weight alkaline phosphatase in patients with colorectal cancer by polyacrylamide gel electrophoresis.

We present a new method for the quantitative determination of high molecular weight alkaline phosphatase (ALP). This method consists of electrophoretic separation on polyacrylamide, incubation of the ALP isoenzymes with substrate, gel drying and quantitative evaluation by densitometric measurement. This method separates high molecular weight ALP from the other isoenzymes. Precision of the method is calculated by the coefficient of variation ranging from 1.2 to 9.5% for samples with different high molecular weight ALP values. The diagnostic sensitivity for detecting colorectal cancer is 60%.