Liquid-Liquid Extraction Combined with Dimethylaminophenacyl Labeling LC-MS for Improved Metabolomic Profiling of Organic Acids

摘要

We have developed an improved isotope labeling method based on liquid-liquid extraction and p-dimethylaminophenacyl reaction for LC-MS metabolomic profiling of organic acid metabolites. About 2500 peak pairs or putative metabolites could be detected using the new method, which are about 3 times as many as that detected in a urine sample prepared using the old method. This method can be used to handle low volumes of urine samples; 2561 ± 27 (n=3), 2548 ± 118 (n=3), and 2301 ± 249 (n=3) peak pairs could be detected in human urine with a starting material of 90, 20 and 10 μL, respectively.