Erasmus Medical Center-Sophia Children's Hospital, Department of Paediatrics, Division of Neonatology, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
Rapid Commun Mass Spectrom. 2009 Dec;23(23):3824-30. doi: 10.1002/rcm.4293.
The use of stable isotope labelled glucose provides insight into glucose metabolism. The 13C-isotopic enrichment of glucose is usually measured by gas chromatography/mass spectrometry (GC/MS) or gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). However, in both techniques the samples must be derivatized prior to analysis, which makes sample preparation more labour-intensive and increases the uncertainty of the measured isotopic composition. A novel method for the determination of isotopic enrichment of glucose in human plasma using liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) has been developed. Using this technique, for which hardly any sample preparation is needed, we showed that both the enrichment and the concentration could be measured with very high precision using only 20 microL of plasma. In addition, a comparison with GC/MS and GC/IRMS showed that the best performance was achieved with the LC/IRMS method making it the method of choice for the measurement of 13C-isotopic enrichment in plasma samples.
稳定同位素标记葡萄糖的使用为了解葡萄糖代谢提供了线索。葡萄糖的 13C-同位素丰度通常通过气相色谱/质谱（GC/MS）或气相色谱/燃烧/同位素比质谱（GC/C/IRMS）来测量。然而，在这两种技术中，样品在分析前必须进行衍生化，这使得样品制备更加繁琐，增加了测量同位素组成的不确定性。我们开发了一种使用液相色谱/同位素比质谱（LC/IRMS）测定人血浆中葡萄糖同位素丰度的新方法。使用这种技术，几乎不需要进行样品制备，我们表明，仅使用 20μL 血浆即可非常精确地测量富集度和浓度。此外，与 GC/MS 和 GC/IRMS 的比较表明，LC/IRMS 方法的性能最佳，使其成为测量血浆样品中 13C-同位素丰度的首选方法。
