Reversed-Phase Dispersive Semi-Microextraction Combined with Gas Chromatography–Mass Spectrometry for the Determination of Polar Components in Oils

Edible and motor oils contain polar and semipolar volatile organic compounds in addition to nonpolar components. Dispersive liquid–liquid microextraction (or semimicroextraction) in the hexane–acetonitrile system can be used for efficient and rapid extraction of these compounds with simultaneous removal of fats from the sample. If the objective is to profile and quantify minor oil components, it is necessary to achieve stable (equilibrium) partition coefficients and degrees of extraction. The experimentally estimated reproducibility (sr, %) of the extraction degrees for ten components of the model mixture at different concentrations was at the level of 5–8%, and it did not exceed 15% when adding samples of different types of motor and edible oils to the extraction system. The key metrological characteristics of GC–MS determination of these compounds were also assessed. The potential for predicting retention parameters using molecular structure descriptors was further explored. The most prognostically significant descriptors of different classes were selected based on the magnitude of the correlation coefficient.