Analysis of [U-13C6]glucose in human plasma using liquid chromatography/isotope ratio mass spectrometry compared with two other mass spectrometry techniques

摘要

The use of stable isotope labelled glucose provides insight into glucose metabolism. The 13C-isotopicenrichment of glucose is usually measured by gas chromatography/mass spectrometry (GC/MS) orgas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). However, in bothtechniques the samples must be derivatized prior to analysis, which makes sample preparation morelabour-intensive and increases the uncertainty of the measured isotopic composition. A novelmethod for the determination of isotopic enrichment of glucose in human plasma using liquidchromatography/isotope ratio mass spectrometry (LC/IRMS) has been developed. Using this tech-nique, for which hardly any sample preparation is needed, we showed that both the enrichment andthe concentration could be measured with very high precision using only 20 ILL of plasma. Inaddition, a comparison with GC/MS and GC/IRMS showed that the best performance was achievedwith the LC/IRMS method making it the method of choice for the measurement of 13C-isotopicenrichment in plasma samples.