A new mass screening method for determining UDP-galactose in blood.

We devised a new microfluorometric mass screening method for determining UDP-galactose by using only one blood disc of 3 mm in diameter. This method contains two coupling enzymes of UDP-galactose-4-epimerase and UDP-glucose dehydrogenase, and conversion of NAD to NADH. The assay ranges are 0 to 1 mM or 0 to 0.2 mM UDP-galactose in blood. UDP-galactose contents were determined in galactosemia of epimerase-, transferase- and kinase-deficiencies, and several cases with high or low Paigen's values.