11. Quantitative Profiling of Bile Acids in Biofluids and Tissues: Compound Class Targeting in a Metabolomics Workflow.

Mon 12:00 PM - PosterSplash Track 2

Ivana Bobeldijk TNO Quality of Life

*Ivana Bobeldijk, *Leon Coulier, *Maarten Hekman, *Raymond Ramaker, #Nadia Ahmad, #Lee Kaplan, *Elwin Verheij * TNO Quality of Life, Utrechtseweg 48, 3700 AJ Zeist, the Netherlands # MGH Weight Center, Massachusetts General Hospital, 50 Staniford St. Boston, MA 02114

We report a sensitive, generic method for quantitative profiling of bile acids and other endogenous metabolites in small quantities of various biological fluids and tissues. In this method, the best of two worlds is combined: comprehensive profiling of endogenous metabolites (metabolomics) and fully validated quantitative determination of bile acids. The method is based on a simple sample preparation, separation by reversed-phase high performance liquid-chromatography mass spectrometry (U(H)PLC-MS) and electrospray in the negative ionisation mode (ESI-). Detection is performed in full scan using the linear ion trap Fourier transform mass spectrometer (LTQ-FTMS or LTQ-Orbitrap) generating data for many (endogenous) metabolites. High specificity, comparable to MS/MS is achieved by the high mass accuracy and high resolution (> 30.000 @ m/z 400). A validation of the method in urine, plasma and liver was performed for 17 bile acids including their taurine, sulphate and glycine conjugates occurring in humans or rodents. Because the matrices to which the method is applied change from study to study, a limited validation is performed within each study. The method was successfully applied to several rodent and human studies in different applications. Examples will be presented where the combination of the comprehensive metabolomics approach with the quantitative approach for bile acids showed to be very useful.

Email: Ivana.Bobeldijk@tno.nl

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