Determination of alpha-tocopherol in cosmetic products by chronopotentiometry

摘要

In the present study, a rapid chronopotentiometric method was developed for the determination of alpha-tocopherol in various cosmetic products. Determination of alpha-tocopherol is based on its irreverse oxidation by constant current at the planar glassy carbon electrode. The influence of the most important experimental parameters of chronopotentiometry was investigated. After optimization, an appropriate procedure for the sample preparation was developed. Under the defined experimental conditions, a detection limit of 7.5 mg L-1 of alpha-tocopherol was obtained. The accuracy of the defined method was confirmed by means of recovery assay. The developed method was successfully applied to quantitation of alpha-tocopherol in various cosmetic products.