1997 Volume 26 Issue 2 Pages 95-100
We have developed a simple automatic method for measuring sulfated bile acids in urine using an enzymatic method. The procedure involves sequential use of enzymes, bile acid sulfate sulfatase, β-hydroxysteroid dehydrogenase and 3-oxo-5β-steroid Δ4-dehydrogenase, followed by reductive color-generating reactions with the hydrogen derived from two dehydrogenase reactions. The present method is characterized by the use of water-soluble tetrazolium WST-1 as a chromogen. The formazan of the reducing product of WST-1 has high water solubility and does not pollute the cuvette or analyzer tube. The calibration curve for glycolithocholic acid 3-sulfate (GLCA-S) as the standard was linear up to 200μmol/l. The CVS for the within- and between-run precisions were 0.5-1.2% and 2.3-2.7%, respectively. Recovery of various sulfated bile acids in urine averaged 100.1%. A good correlation (r=0.995, n=52) was obtained between this automatic method and the manual method previously developed.
