Univariate and multivariate optimization of the separation conditions for the analysis of five bisphenols by micellar electrokinetic chromatography

In this paper we used a chromatographic response function (CRF) that included an output for each of the two performance parameters (resolution and analysis time) to optimize the separation of five bisphenols by micellar electrokinetic chromatography (MEKC) using multivariate response surface methodology (RSM). To validate the real utility of this approach, we have also compared the efficiency of the proposed optimization method with a traditional univariate analysis. For both methods, the selected variables of the analysis were: buffer concentration, pH, amount of organic solvent, and concentration of surfactant. The predictive nature of a validated response surface design allowed for the elucidation of a strong interactive effect and resulted in a more labor-efficient optimization when compared to the univariate approach.