Analysis of the citric acid cycle intermediates using gas chromatography-mass spectrometry

Department of Nutrition, Mouse Metabolic Phenotyping Center, Case Western Reserve University, Cleveland, OH, USA.
Methods in molecular biology (Clifton, N.J.) (Impact Factor: 1.29). 01/2011; 708:147-57. DOI: 10.1007/978-1-61737-985-7_8
Source: PubMed

ABSTRACT Researchers view analysis of the citric acid cycle (CAC) intermediates as a metabolomic approach to identifying unexpected correlations between apparently related and unrelated pathways of metabolism. Relationships of the CAC intermediates, as measured by their concentrations and relative ratios, offer useful information to understanding interrelationships between the CAC and metabolic pathways under various physiological and pathological conditions. This chapter presents a relatively simple method that is sensitive for simultaneously measuring concentrations of CAC intermediates (relative and absolute) and other related intermediates of energy metabolism using gas chromatography-mass spectrometry.

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Available from: Rajan Kombu, Jul 24, 2015
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    • "In recent years, several techniques have emerged that could measure CAC intermediates with greater precision, albeit still with limited coverage. In particular these include LC–MS/MS techniques developed by Luo et al. 2007 (Luo et al. 2007) and Koubaa et al. 2013 (Koubaa et al. 2013), GC/MS methodologies (Dunn and Winder 2011; Kombu et al. 2011), HPLC-fluorescence methodology (Kubota et al. 2005), capillary electrophoresis coupled to a mass spectrometer (CE/MS) (Soga et al. 2003; Wakayama et al. 2010), as well as 1 H NMR (Xu et al. 2011). 1 H NMR permits a greater coverage of the CAC intermediates as well as other metabolites (Xu et al. 2011) and does not require isotopically labeled internal standards. However, it is limited by the low micromolar sensitivity and potential spectral overlap. "
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    • "The mass spectra of the TMS-derivatized compounds formed in the EI source led to fragment ions predicted from their chemical structure. The monitored ions were in accordance with research in which the analytes were determined using the same derivatizing reagent [16] [18]. The quantitation ions for all target compounds, including the internal standard, are shown in Table 2, which also includes the chromatographic retention times. "
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