Liquid Chromatographic and Mass Spectrometric Analysis of Conjugated Bile Acids in Biological Fluids

Abstract

Among various methods used, high-performance liquid chromatography (HPLC) has been well recognized as a powerful tool for separating and determinating biologically important substances, in particular, polar and/or unstable compounds. The great success of this methodology can be ascribed to the development of excellent software for the detection system as well as fine instrumentation and column technology hardware. To obtain high sensitivity and specificity, precolumn derivatization has been widely carried out in labeling with a fluorophore, chromophore or electrophore. However, this technique includes a tedious procedure under nonphysiological conditions. Recently, a hyphenated method with mass spectrometry, LC/MS, has been used with increasing frequency in the bioanalytical field. Among numerous interfaces, electrospray ionization (ESI) has been considered more useful for detection and determination of biologically important compounds containing ionic group (s). In this paper, we describe the separation and determination of bile acids conjugated with sulfic acid or glucuronic acid in biological fluids by LC/ESI-MS.