Simultaneous optimization of the solid-phase extraction of organochlorine and organophosphorus pesticides using the desirability function

In a multi-response situation [solid-phase extraction (SPE) of 18 organochl orine and nine organophosphorus pesticides from aqueous solution], several response variables are considered, and the optimization problem is more com plex than in the single response case. Experimental design combined with de sirability function was applied for the optimization of the SPE of these pe sticides in order to obtain optimum operating conditions for routine work. This multi-criterion approach was developed for the simultaneous optimizati on of multiple responses and it is simple, easy to apply and permits the us er to make subjective judgments on the importance of each response. The des irability function is based on the search for a global optimum [D = f (Y-1, Y-2, ..., Y-n)] by the transformation of the measured property to a dimens ionless scale for each criterion. The experimental design strategy involved a central composite design. A compromise between conflicting goals, such a s achievement of good yields with SPE recoveries of ca. 100% for a large nu mber of analytes with inherent chemical differences, was found by means of the desirability function D.