Analytical and statistical approaches to metabolomics research.

Metabolomics, the global profiling of metabolites in different living systems, has experienced a rekindling of interest partially due to the improved detection capabilities of the instrumental techniques currently being used in this area of biomedical research. The analytical methods of choice for the analysis of metabolites in search of disease biomarkers in biological specimens, and for the study of various low molecular weight metabolic pathways include NMR spectroscopy, GC/MS, CE/MS, and HPLC/MS. Global metabolite analysis and profiling of two different sets of data results in a plethora of data that is difficult to manage or interpret manually because of their subtle differences.

Comparison of 1D and 2D NMR spectroscopy for metabolic profiling.

High-resolution, liquid state nuclear magnetic resonance (NMR) spectroscopy is a popular platform for metabolic profiling because the technique is nondestructive, quantitative, reproducible, and the spectra contain a wealth of biochemical information. Because of the large dynamic range of metabolite concentrations in biofluids, statistical analyses of one-dimensional (1D) proton NMR data tend to be biased toward selecting changes in more abundant metabolites. Although two-dimensional (2D) proton-proton experiments can alleviate spectral crowding, they have been mainly used for structural determination.

Solid-state UV laser-induced fluorescence detection in capillary electrophoresis.

Two solid-state UV lasers were applied to the laser-induced fluorescence (LIF) detection of various groups of compounds after separation by capillary electrophoresis. These lasers are thermoelectric-cooled, highly compact, and inexpensive. Such lasers provide few mW of quasi-continuous wave (CW) power which are sufficient and stable for LIF detection.

Peptide mobility and peptide mapping in capillary zone electrophoresis. Experimental determination and theoretical simulation.

The electrophoretic mobilities of 58 peptides that varied in size from 2 to 39 amino acids and varied in charge from 0.65 to 7.82 are presented.

A simple two-dimensional high performance liquid chromatography/high performance capillary electrophoresis set-up for the separation of complex mixtures.

A two-dimensional high performance liquid chromatography/capillary electrophoresis (HPLC/CE) instrumental set-up was assembled from commercially available equipment. Fractions of the effluent from the HPLC system are collected into microtiter plates with a microfraction collector. The fractions are then dried under vacuum at room temperature, reconstituted, and analyzed by capillary zone electrophoresis (CZE).