Chromatographic figures of merit

J. P. Foley and J. G. Dorsey, Equations for Calculation of Chromatographic Figures of Merit for Ideal and Skewed Peaks, Anal. Chem. 1983,55, 730 ... 

Care must be taken in the use and interpretation of literature efficiency values. Efficiency values are likely the most incorrectly calculated chromatographic figure of merit. The commonly used equations based on peak width at the base or at half the height of the peak are valid only for perfectly Gaussian shaped peaks. This problem has been realized by chromatographers for some time, but the popularity of these methods continues because until recently the only alternative was computer based moment calculations. Kirkland et al. addressed this problem and recommended that peak symmetry values be reported along with efficiency values (8 ). They further showed that the calculation... 

Advantages of this technique are the efficiency of development of methods, structured development profiles, and effective reporting of what was performed during the different method development iterations. In addition, it is possible to model the effect of parameter variation on the robustness of methods in addition to general chromatographic figures of merit apparent efficiency, tailing, resolution of critical pairs, backpressure of system, total run time. 

Foley, J.P. and Dorsey, J.G. (1983) Equations for calculation of chromatographic figures of merit for ideal and skewed peaks. Anal. Chem. 55, 730-737. 

Mertzman M.D., Foley J.P., Effect of surfactant concentration and buffer selection on chromatographic figures of merit in chiral microemulsion electrokinetic chromatography. Electrophoresis, 25, 3247-3256 (2004). 

Kahle KA, Foley JP. Chiral microemulsion electrokinetic chromatography effect of cosurfactant identity on enantio-selectivity, methylene selectivity, resolution, and other chromatographic figures of merit. Electrophoresis 2006 27 4321 333. 

An algorithm for an assesment of chromatographic peak purity was proposed. In this study ethyl 8-methyl-4-oxo-4/7-pyrido[l, 2-u]pyrimidine-3-carboxylate was also used (97MI13). Ethyl 7-methyl-4-oxo-4//-pyrido[l,2-u]pyrimidine-3-carboxylate, among other compounds, was applied to show practical mathematical tools for the creation of several figures of merit of nth order instrumentation, namely selectivity, net analyte signal and sensitivity (96ANC1572). 

It is difficult to compare separation techniques in any general way. Comparison may be based on the traditional figures of merit, such as resolution Rs (including column efficiency N, selectivity, retention, and peak capacity), chromatographic speed, sample capacity, sensitivity, detection and column impedance, as well as breadth of application. Usually a tradeoff between these attributes is found. Berger [26] has compared GC, pSFC, cSFC, LC and CE on the basis... 

The main characteristics of sector mass spectrometers are shown in Table 6.29. Magnetic sector mass spectrometers are often considered more difficult to operate than QMS and ToF-MS the high-voltage source is more demanding to chromatographic interfacing. For figures of merit, see Table 6.27. 

Carbamate Pesticides Environmental Samples Extraction Technique cleanup Technique Reagent/Other Pretreatment Detection Chromatographic Column Analytical Figures of Merit Ref. 

Table 10.5 shows the experimental conditions (stationary phases, mobile phase compositions and detection wavelengths) and figures of merit (linear ranges and limits of detection) of several chromatographic procedures, that employ micellar mobile phases for the analysis of diverse samples. Some procedures have already been commented on in this chapter. However, some aspects still deserve be reviewed, as die use of special mobile phases contairiing two surfactants or microemulsions of SDS and pentanol. 

Table 18.5 Characteristics and figures of merit for automated solid-phase extraction of riboflavin and determination by HPLC-DAD. The procedure proposed by Oliveira et al. (2010) is based on automatic SPE using a renewable column of commercially available molecularly imprinted polymers selective to riboflavin. The solid-phase extraction procedure was coupled online to the reversed phase chromatographic determination, resorting to a monolithic silica C18 column.

Pesticides Type of Water Extraction Technique Cleanup Technique" Derivatization Reagent Determination Technique" Chromatograph ic Column/ Stationary Phase Analytical Figures of Merit References... 

Extraction Technique Analytes Extraction Conditions Chromatographic Column and Detector Figures of Merit and Remark References... 

The prediction of retention data is the basis of the pure mathematical optimization of a chromatographic process. To be useful for this approach, the prediction of the partition coefficient has to be accurate up to a few percent. The resolution Rji which is the figure of merit for the separation will be calculated according to... 

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