Determination of Free and Conjugated Bile Acids in Bile of Ratby High Performance Liquid Chromatography

A method for the determination of free and conjugated bile acids in rat bile by RP-HPLC was established. Bile acids were derivatized with 4-bromomethyl-7-methoxycoumarin and eluted using an acetonitrile/ methanol/ water gradient on a Waters Nova C18 column. Concentrations of each derivatized bile acid were determined by RP-HPLC with fluorescence detection. The assay was linear in the range 5~2 400 μmol/L. The linear regression coefficients ranged from 0.9989 to 0.9997. Recovery was 87.8%~106.7%. The detection limit ranged from 1.2 to 2.5 μmol/L. This method, with wide linear range, is sensitive, reproducible, rapid, and suitable for the determination of bile acids in rat bile in scientific research.