METHOD OF DETECTING SULFATE-CONJUGATED BILE ACID AND TEST PAPER AND BIOSENSOR TO BE USED THEREIN

摘要

A method of sensing or detecting a sulfate-conjugated bile acid comprising as follows. (1a) A sample containing a sulfate-conjugated bile acid is treated with bile acid sulfate sulfatase (BSS) and sulfuric acid thus formed together with beta-hydroxysteroid (B-HSD) is sensed with the use of a pH color-developing reagent. (1b) The B-HSD, which is formed by treating the sample containing a sulfate-conjugated bile acid with BSS, is reacted with NAD<+> in the presence of B-HSD dehydrogenase. Then NADH thus formed is reacted with an electron transporter and H2O2 thus formed is treated with peroxidase. Using oxygen in the generation stage thus generated, a redox color-developing reagent is oxidized to thereby induce color development. (1c) In the above method (1b), the thus formed NADH is reacted with a redox color-developing reagent in the presence of diaphorase to thereby reduce the color-developing reagent, thus inducing color development. (1d) In the above method (1b), the thus formed NADH, preferably also containing the further formed NADH, is reacted with an electron transporter or NADH oxidase. Next, H2O2 thus formed and the reduced electron transporter are oxidized and the electric current thus generated is measured.