Proteomics based on high-efficiency capillary separations.

Identifying and quantifying in a high throughput manner the proteins expressed by cells, tissues or an organism provides the basis for understanding the functions of its constituents at a "systems" level. As a result, proteome analysis has increasingly become the focus of significant interest and research over the past decade. This is especially true following the recent stunning achievements in genomics analyses. However, unlike the static genome, the complexities and dynamism of the proteome present significant analytical challenges and demand highly efficient separations and detection technologies. A number of recent technological advancements have been in direct response to these challenges. Currently, strategically mated combinations of sophisticated separations techniques and advanced mass spectrometric detection represent the best approach to addressing the intricacies of the proteome. Liquid-phase separations, often within capillaries, are increasingly recognized as the best separations technique for this approach. In combination on-line with mass spectrometry, liquid-phase separations provide the improved analytical sensitivity, sample throughput, and quantitation capabilities necessitated by the multifaceted problems within proteomics analyses. This review focuses primarily on current high-efficiency capillary separations techniques, including both capillary liquid chromatography and capillary electrophoresis, applied to the analysis of complex proteomic samples. We emphasize developments at our laboratory and illustrate technical advances that attempt to review the role of separations within the broader context of a state-of-the-art integrated proteomics effort.