Comprehensive multi‐dimensional liquid chromatographic separation in biomedical and pharmaceutical analysis: a review

Abstract

‘Multi‐dimensional’ liquid separations have a history almost as long as chromatography. In multi‐dimensional chromatography the sample is subjected to more than one separation mechanism; each mechanism is considered an independent separation dimension. The separations can be carried out either offline via fraction collection, or directly coupled online. Early multi‐dimensional separations using combinations of paper chromatography, electrophoresis and gels, in both planar and columnar modes are reviewed. Developments in HPLC have increased the number of measurable analytes in ever more complex matrices, and this has led to the concept of ‘global metabolite profiling’. This review focuses on the theory and practice of modern ‘comprehensive’ multi‐dimensional liquid chromatography when applied to biomedical and pharmaceutical analysis. Copyright © 2006 John Wiley & Sons, Ltd.

Theory and Practice of UHPLC and UHPLC–MS

“…Because of the tremendously higher separation power of LC Â LC when compared with its 1D-LC counterpart, the technique has been employed in several fields, e.g., polymers, pharmaceuticals and biological mixtures, natural products, environmental and petrochemical samples, and has been the subject of various reviews (Liu and Lee, 2000;Evans and Jorgenson, 2004;Guttman et al, 2004;Stroink et al, 2005;Dixon et al, 2006;Jandera, , 2012Shalliker and Gray, 2006;Shellie and Haddad, 2006;Dugo et al, 2008a,b;Pol and Hyotylainen, 2008;François et al, 2009a;Herrero et al, 2009;Sandra et al, 2009;Berek, 2010;Pierce et al 2012;Sarrut et al, 2014).…”

Comprehensive two-dimensional liquid chromatographic analysis of anthocyanins

“…Two separation methods are orthogonal if the separation mechanisms involved are independent of each other and show distinct retention profiles or provide different selectivities [115]. However, many separation modes have retention mechanisms in common, making the realisation of perfect orthogonality in practice difficult [116,117]. In essence, the advantage of an LC×LC separation is not fully utilised if the entire 2-dimensional separation space is not completely utilised, and this require the combination of orthogonal separations.…”

Future of Liquid Chromatography–Mass Spectrometry in Metabolic Profiling and Metabolomic Studies for Biomarker Discovery

“…This increase is generally due to improved detection of lower abundance species, which are ultimately better resolved from species that are present either in higher abundance or have higher proton affinities or surface activities. A direct approach for increasing the separation peak capacity is through the inclusion of additional separation dimensions (reviewed in [110]), although the incorporation of multiple separation dimensions can result in increased analysis time and sample consumption. However, Stoll et al [111] recently reported the development of a high speed, comprehensive online 2D-LC-UV method based on the use of ultra-fast, high temperature gradient chromatography and the application of this method to the analysis of the low molecular weight components of maize seedlings.…”