Continuous-flow fluorometry of low galactose concentrations in blood or plasma.
Clearance of 0-100 mg/L concentrations of galactose from the blood depends on nutrient hepatic blood flow. We can measure such concentrations, which was not previously possible, by a continuous-flow method involving the use of galactose oxidase and peroxidase, the latter being coupled to a fluorogenic substrate, p-hydroxyphenylacetic acid. Interfering substances in the peroxidase reaction are removed by zinc/alkali precipitation. Sensitivity is maximized by using saturating concentrations of the enzymes and substrate. In prepared plasma test samples with galactose concentrations of 10, 40, 70, and 100 mg/L, the within-run CV's ranged from 2.1 to 8.6%, and day-to-day CV's from 2.2 to 17.2%, the largest CV's being for the 10 mg/L concentration. Normal subjects are shown to clear galactose more efficiently than subjects with moderate cirrhosis.
D000925:Anticoagulants; D005470:Fluorometry / Q000379:methods*; D005690:Galactose; D005693:Galactosemias; D006801:Humans; D008099:Liver / Q000098:blood supply; D008103:Liver Cirrhosis / Q000097:blood; D012039:Regional Blood Flow; D013048:Specimen Handling
D000925:Anticoagulants; D005690:Galactose