High Throughput, Sensitive LC-MS/MS Determination of Bile Acids in Mouse Feces and its Application to Monitoring their Levels of Excretion

A new rapid high-throughput liquid chromatography with tandem mass spectrometry detection method (LC-MS/MS) was developed for the analysis of chenodeoxycholic acid, cholic acid (primary bile acids) and deoxycholic acid, lithocholic acid, ursodeoxycholic acid (secondary bile acids), from mouse feces. Analytical separation was performed on a Zorbax SB-C18 column with mobile phase consisting of methanol and water in gradient elution, using the detection in single ion monitoring mode, with atmospheric pressure chemical negative ionization. The method was validated with respect to selectivity, linearity (r(2) > 0.99), intra-day precision (CV < 13.81%), accuracy (bias < 5.71%) and can be applied to monitor the simultaneously excretion of bile acids in cases of experimentally studies in which the development of colon cancer diet related models that implicate both primary and secondary bile acids are proposed. This analytical method has the advantage of a total run-time of 6 minutes and the limitation of the following lower limits of quantification: 0.095 mu g/mL cholic acid, 0.116 mu g/mL ursodeoxycholic acid, 0.120 mu g/mL chenodeoxycholic add, 0.230 mu g/mL deoxycholic acid and 0.274 mu g/mL lithocholic acid.