BART: A transferable liquid chromatography retention time library for bile acids.

Area of Science:

• Analytical Chemistry
• Biochemistry

Background:

• Accurate identification of bile acids, particularly isomers, relies on reference standards, which are often unavailable.
• Published liquid chromatography (LC) retention data is not transferable between labs due to system variations.

Purpose of the Study:

• To develop a transferable bile acid retention time library (BART) for improved identification and data consistency.
• To create a software tool for predicting gradient retention times across diverse LC systems.

Main Methods:

• Developed isocratic retention models for 272 bile acids using the quadratic solvent strength model (QSSM).
• Created a software tool to predict gradient retention times, incorporating system-specific parameters like holdup and dwell times.
• Validated the BART approach on multiple LC-MS systems across different laboratories.

Main Results:

• The BART library and prediction tool demonstrated high accuracy, with average root mean square errors (RMSE) of 0.052-0.054 min.
• Predicted retention times were nine times more accurate than those from static retention time libraries.
• The method showed robust performance across various LC-MS systems and gradient methods.

Conclusions:

• BART provides a reliable and transferable method for predicting bile acid retention times, significantly aiding in isomer identification.
• The developed library and software tool enhance data reproducibility and facilitate bile acid analysis in different laboratory settings.
• The BART library is freely accessible, promoting wider adoption and advancement in bile acid research.