High-throughput bioanalysis of bile acids and their conjugates using UHPLC coupled to HRMS

Background: Quantitative assessment of bile acids in biological matrixes is of growing interest, primarily due to hepatic toxicity resulting from drug interactions with the bile salt export pump. Nevertheless, many bile acids demonstrate poor fragmentation in MS, making conventional MS/MS not a good match for their selective quantitation in biological matrices. Results: The current study was designed to evaluate the feasibility of simultaneous quantitation of 19 bile acids using HRMS coupled to UHPLC separation with minimal instrument optimization. An effective chromatography was developed using an Agilent Zorbax (R) Eclipse XDB-C18 column (1.8 mu m, 50 x 2.1 mm internal diameter), achieving separation of 19 compounds in 10 min. Excellent assay reproducibility was demonstrated, with two sets of standard curves, run 42 days apart. Conclusions: The results show that LC-HRMS is a viable platform for high throughput bioanalysis of bile acids especially in a drug-discovery setting.