DEVELOPMENT OF AN ADVANCE METHOD FOR THE DETERMINATION OF TOCOPHEROLS IN EDIBLE OILS

We have developed a method for the determination of tocopherols in different edible oils by RP-HPLC, using a FLD detector, a Poroshell column as a stationary phase, and a mixture of acetonitrile, methanol and water (5:4.5:0.5) as mobile phase (flow rate 0.75 ml/min). The structure of the compounds was identical, so it could not be separated by reverse phase liquid chromatography. The obtained peaks show an important overlapping and we have used chemometric tools to get a calibration model, which assumes a linear behavior, i.e., the total signal is the sum of individual signals of components. Recovery percentages were between 90.3% and 95.7%. The method has been successfully applied to edible oils and dietary supplements. No pretreatment of the samples was needed.