Development and Validation of a GC-MS/MS Method for the Simultaneous Quantification of Selected Compounds in Essential Oils

Abstract

The benefits from the everyday use of essential oils are associated with well-known antimicrobial, anti-inflammatory, and antioxidant activity of their constituents. Considering this, compounds within essential oils are the focus of extensive research, necessitating the development of analytical methods for their simple and rapid determination. In this study, a method for the quantitation of p-cymene, limonene, eucalyptol, linalool, menthol, and carvone in essential oils was developed and validated. Gas chromatography-tandem mass spectrometry (GC-MS/MS) was employed for the separation and determination of the selected compounds. Standard solutions of six analytes were prepared using hexane as the solvent. A triple quadrupole mass spectrometer, operated in dMRM scan mode, was used to monitor specific transitions at their optimal collision energies (quantifier and two qualifiers for each compound). Gas chromatography was optimised by adjusting the oven temperature gradient programme to achieve efficient separation in a short run time of 14 min. All calibration curves showed good linearity (R2 ≥ 0.998), with the concentration ranges varying depending on the analyte (0.10–10.00 μg ml–1). The method was validated for accuracy (80.23–115.41 %), intra-day precision (≤ 12.03 %), and inter-day precision (≤ 11.34 %). The validation followed ICH guidelines, and all tested parameters were found to be satisfactory. This confirms the method’s suitability for the simultaneous individual determination of these compounds in essential oils. The method was successfully applied in the analysis of essential oils from lemon, tangerine, grapefruit, eucalyptus, myrtle, niaouli, peppermint, and fennel.

Keywords

• essential oils
• gc-ms/ms
• triple quadrupole
• mrm transition
• validation