Rapid determination of 20 bile acids in human serum by ultra performance liquid chromatography-tandem mass spectrometry

Analysis of 15 bile acids in human plasma based on C18 functionalized magnetic organic polymer nanocomposite coupled with liquid chromatography-tandem mass spectrometry

Because of the "enterohepatic circulation" of bile acid, liver damage can be reflected by monitoring the content of bile acid in the serum of the organism. To monitor the concentration of 15 bile acids in plasma samples, a new technique of PRiME (process, ruggedness, improvement, matrix effect, ease of use) pass-through cleanup procedure combined with high performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS/MS) was developed. The sorbent used in the PRiME pass-through cleanup procedure is a new type of magnetic organic resin composite nano-material modified by C18 (C18-PS-DVB-GMA-Fe3O4), which has high cleanup efficiency of plasma samples. It also shows good performance in the separation and analysis of 15 kinds of bile acids. Under the optimal conditions, the results show higher cleanup efficiency of C18-PS-DVB-GMA-Fe3O4 with recoveries in the range of 82.1-115 %. The limit of quantitative (LOQs) of 15 bile acids were in the range of 0.033 µg/L-0.19 µg/L, and the RSD values of 15 bile acids were in the range of 3.00-11.9 %. Validation results on linearity, specificity, accuracy and precision, as well as on the application to analysis of 15 bile acids in 100 human plasma samples demonstrate the applicability to clinical studies.

A dynamic multiple reaction monitoring strategy to develop and optimize targeted metabolomics methods: Analyzing bile acids in capecitabine-induced diarrhea

OBJECTIVE

We sought to develop and optimize a targeted bile acids (BAs) metabolomics method based on a dynamic multiple reaction monitoring (dMRM) strategy and explored the dynamic alterations of BAs in diarrhea induced by capecitabine in a mouse model.

METHOD

The targeted metabolomics method was developed using an Agilent 6460A triple quadrupole mass spectrometer, and 41 types of BAs were monitored in negative ionization mode. The mass spectrometer detection was optimized using dMRM to enhance the responses, separation, and peak shape and to shorten the analysis time. A mouse model of diarrhea was established by multiple administration of capecitabine, and plasma samples were collected at baseline and the end of drug administration for subsequent BAs analysis.

RESULTS

The targeted BA metabolomics method achieved shorter chromatographic separation time (10 min) for 41 BAs, with good peak shapes and response increases of 3- to 10-fold after application of dMRM. The mouse model of capecitabine-induced diarrhea was established, and the three BAs 23-norcholic acid, isolithocholic acid, and isodeoxycholic acid in the baseline samples contributed the most to differentiating mice with diarrhea from those without diarrhea. For mice that ultimately developed diarrhea, apocholic acid, isodeoxycholic acid, and 7-ketodeoxycholic acid exhibited the largest change in concentrations compared with their baseline concentrations.

CONCLUSION

The dMRM strategy has obvious advantages compared with common MRM. The results in model mice showed that a differentiated profile of BAs in the baseline may indicate biomarkers of diarrhea induced by capecitabine, and disturbed homeostasis may explain the metabolomic mechanism of diarrhea occurrence.