Theory, chromatography resolution

In a chromatographic separation, the individual components of a mixture are moved apart in the column due to their different affinities for the stationary phase and, as their dispersion is contained by appropriate system design, the individual solutes can be eluted discretely and resolution is achieved. Chromatography theory has been developed over the last half century, but the two critical theories, the Plate Theory and the Rate Theory, were both well established by 1960. There have been many contributors to chromatography theory over the intervening years but, with the... 

Recalling that a separation is achieved by moving the solute bands apart in the column and, at the same time, constraining their dispersion so that they are eluted discretely, it follows that the resolution of a pair of solutes is not successfully accomplished by merely selective retention. In addition, the column must be carefully designed to minimize solute band dispersion. Selective retention will be determined by the interactive nature of the two phases, but band dispersion is determined by the physical properties of the column and the manner in which it is constructed. It is, therefore, necessary to identify those properties that influence peak width and how they are related to other properties of the chromatographic system. This aspect of chromatography theory will be discussed in detail in Part 2 of this book. At this time, the theoretical development will be limited to obtaining a measure of the peak width, so that eventually the width can then be related both theoretically and experimentally to the pertinent column parameters. 

In a chromatographic separation procedure the parameters of the chromatographic system (stationary phase, flow, temperature, etc.) have to be selected respectively optimized with respect to some criterion (resolution, time, etc.). In gas chromatography retention data series are published and used for the sttidy of solvent/solute interaction, prediction of the retention behaviour, activity coefficients, and other relevant information usable for optimization and classification. Several clKmometrk techniques of data anal s have been employed, e.g. PCA, numerical taxonomic methods, information theory, and j ttern recognition. 

G. R. Asbury and H. H. Hill, Jr., Evaluation of Ultrahigh Resolution Ion Mobility Spectrometry as an Analytical Separation Device in Chromatographic Terms, J. Microcolumn Sep. 2000,12, 172 H. E. Revercomb and E. A. Mason, Theory of Plasma Chromatography/Gaseous Electrophoresis, Anal. Chem 1975,47,970. 

FFF is a separation technique that encompasses a range of procedures based on theory and subsequent instrumentation originally developed and advanced by Gid-dings.75-76 FFF is a high-resolution chromatography-like technique applicable to the separation of macromolecules, colloids and particles encompassing a size range of... 

Dorsey JG. Column Theory and Resolution in Liquid Chromatography. In Meyers, RA (ed). Encyclopedia of analytical chemistry. Chichester John Wiley 8c Sons, 2000 11334-42. 

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