Optimization by Dependent Variables

In general, chiral pollutants occur in the environment at low concentrations and, therefore, sensitive detection is essential. The most commonly used 

Only few reports are available in the literature that deal with the detection limits for chiral resolution of pollutants by CE, the pollutant concentrations ranging from mg 1 to ng 1 Tsunoi etal. [20] carried out an extensive study on the determination of detection limits for the chiral resolution of herbicides. The authors used a wavelength of 230 nm for detection and the minimum detection limit achieved was 4.7 x 10 M for 2,4-dichlorophenoxy acetic acid. On the other hand, Mechref and El Rassi [37] reported better detection limits, for herbicides, in the derivatized mode in comparison to the underivatized mode. For example, the detection limit was enhanced by almost one order of magnitude, from 1 x 10 M (lOpmol) to 3 X 10 M (0.36 pmol). In the same study, the authors reported 2.5 x 10 Mandl x 10 Mas the detection limits for herbicides by fluorescence and laser induced fluorescence detectors, respectively. 

CE is a fast-growing, efficient and versatile technique for the chiral resolution of dmgs, pharmaceuticals and environmental pollutants, but its working conditions still need to be improved to achieve reproducibility. To the best of our knowledge, only a few reports are available in the literature on method validation related to the determination of environmental pollutants by CE [52]. Therefore, at the present time, more emphasis should be placed on method validation. For routine analysis, it is essential to keep the migration time constant in order to allow automatic peak identification by means of commercial data analysis software. Automatic peak identification and quantification are only possible if the relative standard deviation of the migration time is less than 0.5 % [53]. Several reviews have been published that describe improvements in the reproducibility of results [53-59]. 

Another approach to qualitative and quantitative reproducibilities is the transformation of the total time scale (the x-scale) of the electrophoretic 

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