In clinical analyses, the most appropriate biofluid should be analyzed for optimal assay performance. For biological fluids, the most readily accessible is blood, and metabolomic analyses can be performed either on plasma or serum. To determine the optimal agent for analysis, metabolic profiles of matched human serum and plasma were assessed by gas chromatography/time-of-flight mass spectrometry and ultrahigh-performance liquid chromatography mass spectrometry (in positive and negative electrospray ionization modes). Comparison of the two metabolomes, in terms of reproducibility, discriminative ability and coverage, indicated that they offered similar analytical opportunities. An analysis of the variation between 29 small-cell lung cancer (SCLC) patients revealed that the differences between individuals are markedly similar for the two biofluids. However, significant differences between the levels of some specific metabolites were identified, as were differences in the intersubject variability of some metabolite levels. Glycerophosphocholines, erythritol, creatinine, hexadecanoic acid, and glutamine in plasma, but not in serum, were shown to correlate with life expectancy for SCLC patients, indicating the utility of metabolomic analyses in clinical prognosis and the particular utility of plasma in relation to the clinical management of SCLC.

Original publication

DOI

10.1021/ac2012224

Type

Journal

Anal Chem

Publication Date

01/09/2011

Volume

83

Pages

6689 - 6697

Keywords

Chromatography, High Pressure Liquid, Creatinine, Erythritol, Gas Chromatography-Mass Spectrometry, Glutamine, Glycerylphosphorylcholine, Humans, Lung Neoplasms, Mass Spectrometry, Metabolomics, Palmitic Acid, Plasma, Serum, Small Cell Lung Carcinoma