title: Quantitative analysis of bile acids in human plasma by liquid chromatography-electrospray tandem mass spectrometry: a simple and rapid one-step method.
abstract: Bile acids play a pivotal role in the metabolism of cholesterol and lipids. Their blood concentrations are important prognostic and diagnostic indicators of hepatobiliary and intestinal dysfunction. This class of molecules comprises a heterogeneous group of compounds with a common cholesterol scaffold. Recently, the introduction of liquid chromatography coupled to tandem mass spectrometry methods has revealed an innovative path in the quantisation of specific bile acids in biological specimens. A robust and sensitive method has been developed based on high performance liquid chromatography separation coupled to an electrospray triple-quadrupole mass spectrometer. Human plasma samples were analysed on a C18 reverse-phase column. The elution profiles were monitored in multiple reaction-monitoring mode, quantifying and identifying each analyte by its own unique precursor to product patterns. A linear correlation over a broad range of bile acid concentrations (0.1-100 microM) was observed. The average recovery period for all of the analysed bile acids was 98 +/- 3%. Intra-day and inter-day precision averages were 2% and 5.4%, respectively. The determination was achieved within a single chromatographic run for all unconjugated, glycine- and taurine-conjugated isomeric forms of bile acids. As a proof of principle this method has been validated on a small subset of cholestatic patients (n = 7) and compared to appropriate clinical controls (n = 10). Based upon our encouraging experimental results, the described HPLC separation coupled to tandem mass spectrometry method for the analysis of bile acids in biological samples is deemed a robust and accurate procedure. Consequently, we propose this technique as a suitable candidate method for the identification and quantitation of bile acids in routine analysis.
authors.affiliation: Laboratorio di Biochimica Clinica, Ospedale Pediatrico del Bambino Gesù - IRCCS, Rome, Italy,
authors.forename: Debora
authors.initials: D
authors.lastname: Tagliacozzi
authors.forename: Alessia F
authors.initials: AF
authors.lastname: Mozzi
authors.forename: Bruno
authors.initials: B
authors.lastname: Casetta
authors.forename: Pierfrancesco
authors.initials: P
authors.lastname: Bertucci
authors.forename: Sergio
authors.initials: S
authors.lastname: Bernardini
authors.forename: Carmine
authors.initials: C
authors.lastname: Di Ilio
authors.forename: Andrea
authors.initials: A
authors.lastname: Urbani
authors.forename: Giorgio
authors.initials: G
authors.lastname: Federici
mesh_terms: D001646:Bile / Q000737:chemistry; D001647:Bile Acids and Salts / Q000097:blood*; D002138:Calibration; D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D001647:Bile Acids and Salts