An acid hydrolysis method for quantification of plasma free and total carnitine by flow injection tandem mass spectrometry.

摘要

OBJECTIVES: To develop a tandem mass spectrometry (MS/MS) method for plasma free and total carnitine, incorporating acid hydrolysis for total carnitine measurement, for improved accuracy and sample throughput. DESIGN AND METHODS: Limit of detection (LOD), limit of quantitation (LOQ), linearity, accuracy, precision coefficient of variation (CV), method comparison with a radioenzymatic assay (REA) and liquid chromatography tandem mass spectrometry assay (LC-MS/MS) were performed. The method was tested for interferences and for long-term performance. RESULTS: The method LOD and LOQ were 0.87 and 1.36 mumol/L for free carnitine and 1.79 and 2.54 mumol/L for total carnitine, respectively. No interferences were detected. Long-term measurement CVs for both free and total carnitine were <4%. CONCLUSIONS: The method shows acceptable performance characteristics with improved speed and low level accuracy compared to existing REA and MS/MS methods.