High-performance liquid chromatography-tandem mass spectrometry for the analysis of bile acid profiles in serum of women with intrahepatic cholestasis of pregnancy.

A simple, sensitive, and specific high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for the analysis of the bile acid profile has been developed. Fifteen bile acids, including free and conjugated bile acids, were separated and detected by HPLC-MS/MS. The MS detection was performed by electrospray ionization (ESI) in negative ion mode. Quantification was achieved in multiple reaction monitoring (MRM) mode with external standard curve methods. Total analysis time was 15 min for one sample including re-equilibration time of the column. The assay was linear in the range 0.02-100.0 micromol/L with correlation coefficients of standard curves for all bile acids better than 0.999. The detection limits ranged from 0.001 to 0.006 micromol/L for different bile acids. The precisions for each bile acid were CVs<3.8% for within-day and CVs<6.1% for between-day. The average recoveries for all bile acids studied were in the range of 86-110.0%. The developed method was applied to the analysis of clinic samples consisting of 53 women with healthy pregnancies and 43 women with intrahepatic cholestasis of pregnancy (ICP). The results revealed that the bile acid profile was markedly different between women with ICP and women with healthy pregnancies.