Separation of preservatives in cosmetic products by micellar electrokinetic chromatography.

This paper describes the methodological optimization and validation of a simple micellar electrokinetic chromatography for the rapid simultaneous separation of 2-methyl-4-isothiazolin-3-one, methylparaben, ethylparaben, propylparaben, and butylparaben. By using a 30 mM phosphate buffer (pH 7.2) containing 30 mM sodium dodecyl sulfate (SDS), an applied voltage of 10 kV and a separation temperature of 40 degrees C, a quantitative determination was achieved, resulting in an analysis time of approximately 4 min. Only dilution and filtration are needed before analysis. The parameters for validation, such as linear ranges, detection limits, accuracy, and precision, are also reported.