Resolution in chromatography

Effect of porous structure of the SMC on resolution in chromatography of proteins Theoretical aspects Anion Exchange disks [75]... 

Riley, C. M., Efficiency, retention, selectivity and resolution in chromatography, in High Performance Liquid Chromatography, Fundamental Principles and Practice (W. J. Laugh and I. W. Wainer, eds.), Blackie Academic and Professional, Glasgow, 1996, pp. 29-35. 

Super-resolution in chromatography is defined as the ability to detect the presence of two or more components when their mean elution tines fall within two standeurd peak widths of each other. Numerical deconvolution techniques for achieving superresolution eu e considered for the case of a single channel detector (7ZD), a multichannel detector (HS) and a two dimensional detector (video fluorometer). It is shown that the degree of ambiguity of the deconvolution decreases in going from a monochannel detector to a multicdiannel detector to a multidimensional detector. Three types of analytical situations are considered for each type of detector ... 

Figure l. A computer simulated example of the need for super-resolution in chromatography. The coa site curve, shown as a solid line, is the sum of three gaussian components occurring at time channels 45, 50 and 58,... 

Numerical deconvolution appears to be a viable approach to obtaining higher resolution in chromatography. In the case where... 

Design of the separation. It is well known that gradients can improve apparent resolution in chromatography (1). The use of a gradient in a separation such as that shown in Figure 6a would be ideal in that adequate clearance of the polar contaminants could... 

The most obvious sources of error in analyses are related to insufficient extraction, low and irreproducible recoveries, insufficient peak resolution in chromatography, and the transformation of mercury species that may lead to artifacts. In the case of solubilized samples such as fish and mussels, speciation analysis was generally successful. However, with solids, techniques to remove or solubilize MeHg are complicated to validate by using spiking or tracer approaches, as it is difficult to prove that complete extrac-tion/separation has been achieved. A classical example of this difficulty is speciation of MeHg in sediments and soils. The only feasible approach adopted in certification of MeHg is to use different analytical approaches - that is, various extraction/sep-aration schemes and detection methods... 

Traditional procedures of detecting oligomers contained in polymer samples are based on gas, liquid, and size exclusion chromatography (SEC), combined with several structure identification methods. These techniques are indeed powerful, but sometimes low volatility of samples, low solubility in suitable organic solvent, or low resolution in chromatography make alternative and rapid methods of detection and direct identification of mixtures highly desirable. 

The resolution between neighboring peaks is another common optimization goal. There are two approaches to influence resolution in chromatography ... 

Thus resolution in chromatography is a function of three factors selectivity (S), efficiency ( ), and capacity (C) ... 

It is well known that a chiral environment is essential for enantiomeric resolution in chromatography, and this is also true in the case of chiral CE. In CE, this chiral situation is provided by the chiral compound used in the BGE, which is called a chiral selector or a chiral BGE additive. Basically, the chiral recognition mechanisms in CE are similar to those in chromatography using a chiral mobile phase additive mode, except that in the case of CE the resolution occurs through the different migration velocities of the diastereoisomeric complexes. Chiral resolution takes place due to the formation of diastereomeric complexes between the enantiomers of the pollutants and the chiral selector, and this depends on the type and nature of the chiral selectors used and the pollutants. 

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