Simultaneous optimization of surfactant concentration and organic modifierin micellar liquid chromatography. Application to the separation of phenolic compounds

The separation selectivity of eighteen phenolic derivatives in micellar hig h-performance liquid chromatography was studied as a function of parameters on which it depends: surfactant and organic modifier concentration. The su rfactant used in this study was cetyltrimethylammonium bromide, and as orga nic modifier methanol. An iterative regression optimization strategy for th ese two parameters has been used. The equation that best explains the exper imental -results is 1/k' = A -tB mu + C phi + D mu phi.We propose the use o f this model in conjunction with the appropriate factorial design to predic t the solute retention behaviour in micellar liquid chromatography with hib rid eluents.