Abstract
The multiβcriteria decision making (MCDM) method was applied for the optimization of the separation of eight coumarin compounds in mixed micellar liquid chromatography (MLC). In order to achieve this goal the usefulness of Derringer's desirability function for the evaluation of the two different chromatographic performance goals (resolution and analysis time) was tested. The effect of six experimental parameters on a chromatographic response function (CRF) expressed as a product of two sigmoidal desirability functions was investigated. The sigmoidal functions were used to transform the optimization criteria, resolution and analysis time, into the desirability values. The factors studied were the concentration of sodium dodecyl sulfate (SDS) and polyxyethylene (23) dodecanol (Brijβ35), alkyl chain length of the alcohol used as the organic modifier, organic modifier concentration, mobile phase pH and temperature. For the development of the method and the optimization of the chromatographic conditions, the experiments were performed according to a faceβcentered cube response surface experimental design. The qualities of the obtained chromatograms were calculated using CRF and model was built by the use of MLR to correlate the obtained CRFs to the variables and their interactions. The MLR model developed showed good descriptive and predictive ability (R^2^β=β0.998, Fβ=β626.056, SEβ=β0.009, R^2^~CV~β=β0.985) and was used, by a grid search algorithm, to optimize the chromatographic conditions for the separation of the mixture. The efficiency of prediction of polynomial model was confirmed by performing the experiment under the optimal conditions. The results of the study indicated that a CRF composed of sigmoid transformations can also be successfully used for the evaluation of the chromatograms. Copyright Β© 2007 John Wiley & Sons, Ltd.