Editorial pubs.acs.org/ac
Multidimensional Separations Daniel W. Armstrong,† Associate Editor, Analytical Chemistry, Staci L. Massey Simonich,‡ Associate Editor, Environmental Science & Technology
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he potential power of multidimensional separations, in terms of peak capacities and for the analysis of complex samples, has been recognized since the mid-1940s when planar chromatographic and, later, slab gel electrophoresis techniques were used to separate complex samples in space (as opposed to time). Prior to the development of practical, comprehensive, column-chromatographic systems, the importance of uncorrelated or orthogonal separation systems and basic theory covering peak capacity, peak overlap, resolution, etc. was largely understood. However, proper hardware, especially effective modulator systems, plus the software and algorithms needed to handle, treat, and display the enormous amounts of data involved had to be developed. This issue focuses largely on comprehensive 2D chromatography where the entire first-dimension separation is subject to the second dimension separation. It is this comprehensive approach that required the aforementioned advances in hardware and software in order to become a practical tool for most chemists. The rapid expansion of fundamental and applied multidimensional separations investigations have roughly paralleled the “explosion” in “omics” research; e.g., metabolomics, proteomics, petroleomics, genomics, lipidomics, foodomics, pharmaceogeonics, etc. Some areas and complex samples are better addressed by GC × GC (petroteomics, for example), others by LC × LC (proteomics, for example), and still other by both or a combination thereof (LC × GC). Often there is another added dimension associated with detection, e.g., MS, MS/MS, diode array, etc. which further increases the power, complexity, and information obtained in multidimensional separations. Comprehensive 2D-GC (GC × GC) became a viable, practical, and successful-commercial method well before comprehensive 2D-LC (LC × LC). GC × GC can effectively utilize different compact modulation systems, and the data handling and plotting software have gone through several iterations. New orthogonal column combinations have been developed to more fully exploit the separation window. Currently, GC × GC is a more mature technique than LC × LC, and this is reflected in the relative number of papers published in these areas, especially in the number of successful applications. The focus of the papers in this Virtual Issue is on the development and use of multidimensional gas chromatography and liquid chromatography. Given its maturity, there is a preponderance of GC × GC papers particularly in the area of environmental applications. Also included are papers on multidimensional LC, the combination of LC−GC and a 4D preparative system. The papers selected from Analytical Chemistry and Environmental Science & Technology are indicative of the growing importance of multidimensional separations in many areas of science and technology. It is clear that this area of research will continue to develop and expand in the foreseeable future. © XXXX American Chemical Society
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Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, Texas 76019, United States ‡ Department of Environmental and Molecular Toxicology and Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, United States
AUTHOR INFORMATION
Notes
Views expressed in this editorial are those of the author and not necessarily the views of the ACS.
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dx.doi.org/10.1021/ac503953m | Anal. Chem. XXXX, XXX, XXX−XXX
