A flow-injection procedure for the indirect determination of a primal)' bile acid (cholyl glyci.1e) using immobilized 7a-hydroxysteroid dehydrogenase and co-immobilized bac­terial luciferase and oxidoreductase is described. The linear range is lxlO·6_1xlO,3 M cholyl glycine. The reproducibility is less than 3.4% (n =5) and the sample throughput is 60 m-l.


A NABI ,P J WORSFOLD ,