Abstract
A micellar electrokinetic capillary chromatography (MECC) method suitable for the determination of antioxidants and preservatives permitted in cosmetic products is described. Unlike reversed phase high performance liquid chromatography (HPLC) this method simultaneously separates ionic solutes (sorbic acid and benzoic acid) and non-polar components (butylated hydroxytoluene and dodecyl gallate). A buffer consisting of 15 mM sodium dodecyl sulfate, 35 mM sodium cholate, 10 mM boric acid, and 10 mM sodium tetraborate adjusted to pH 9.5 and an 80 cm (total length) bare fused silica column gave good separations. The determination of additives in some cosmetic products was performed using both MECC and HPLC. There was good agreement between the methods.
ACKNOWLEDGMENT
This research was supported by a grant received from Edith Cowan University, Perth, Australia.