Metabolomik: Open Access

Consistency of Metabolite Determination from NMR Spectra over Time and Between Operators

Abstract

Tso V, Eisner R, Macleod S, Ismond KP, Foshaug RR, Wang H, Joseph R, Chang D, Taylor N and Fedorak RN

With the recent increase in publications of metabolomic-based studies, it is apparent that there are considerable differences in findings between laboratories. Even within a single centre, variability introduced by different highly skilled operators contributing to the same experiment can alter the results. These inconsistencies may contribute to unforeseen experimental confounders and, as such, represent a critical barrier to metabolomics based studies. This issue can impact studies throughout the research spectrum, from basic science to clinical research. One of the potential sources of unforeseen variance in many metabolomic-based studies occurs during the identification and quantification of metabolites. In our study, we examined the profiling consistency of NMR spectra as essential to the interpretation and analysis of metabolite concentrations. This manuscript describes how to evaluate the consistency of metabolite identification and quantification from NMR spectral profiling, between operators and over time, and this methodology can be applied to other quantification techniques in the ‘omics’ realm. We also present the results of our analysis, ranking the urine metabolites’ consistency via NMR quantification. Results from this study will allow metabolomics researchers to better assess consistency and thus ensure that metabolite differences truly reflect biological differences rather than experimental variability.