ABSTRACT
Acylcarnitines are metabolic intermediates of fatty acids and branched-chain amino acids having vital biofunctions and pathophysiological significances.Here,we developed a high-throughput method for quantifying hundreds of acylcarnitines in one run using ultrahigh performance liquid chromatography and tandem mass spectrometry(UPLC-MS/MS).This enabled simultaneous quantification of 1136 acyl-carnitines(C0-C26)within 10-min with good sensitivity(limit of detection＜0.7 fmol),linearity(cor-relation coefficient＞0.992),accuracy(relative error＜20％),precision(coefficient of variation(CV),CV＜15％),stability(CV＜15％),and inter-technician consistency(CV＜20％,n=6).We also established a quantitative structure-retention relationship(goodness of fit＞0.998)for predicting retention time(tR)of acylcarnitines with no standards and built a database of their multiple reaction monitoring parameters(tR,ion-pairs,and collision energy).Furthermore,we quantified 514 acylcarnitines in human plasma and urine,mouse kidney,liver,heart,lung,and muscle.This provides a rapid method for quantifying acyl-carnitines in multiple biological matrices.