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A method based on the use of HPLC for the enantioselective resolution of the four stereoisomers of methyl jasmonate (MJ) with no need for the previous formation of the diastereoisomers is developed. To that end, a Nucleodex‐β‐PM column as well as an optimization process considering different flow rates and mobile phase compositions were required. As a result, 0.8 mL/min and 55:45 methanol/water composition were the conditions selected to carry out the separation of the stereoisomers. Isolation of pure (–)‐ and (+)‐MJ was accomplished by collecting the HPLC fractions corresponding to their elution time. SPE was subsequently used to concentrate and change the solvent of the HPLC fractions collected. Chiral GC and polarimetry were additionally employed to evaluate the purity and optical rotation, respectively, of the enantiomers separated. The results found in this study are particularly relevant considering that MJ stereoisomers are not commercially available.

A fully automated method for the determination of medium volatility compounds in aromatic samples was developed. Specifically, the determination of methyl jasmonate in jasmine fragrances was performed by using the through oven transfer adsorption–desorption (TOTAD) interface for the on‐line coupling between RPLC‐GC. A study of the most relevant variables involved in the performance of the TOTAD interface for medium volatility compounds was carried out by testing different values of helium flow (100, 300, 400, and 500 mL/min), transfer speed (0.1, 0.3, 0.5, and 2.0 mL/min), and methanol/water percentages (86:14, 85:15, 83:17, 80:20, and 70:30). The method developed provided satisfactory repeatability (RSD for retention times of 0.15% and for peak areas of 9.4%) and recovery (71%) as well as excellent LOD (0.01 mg/L) for methyl jasmonate in commercial jasmine essence under the experimental conditions selected as optimum. Additional advantages of the automated RPLC‐TOTAD‐GC method proposed in the present work are its rapidness, reliability, and the possibility of directly introducing the sample with no further pretreatment.

A method based on the use of absorbents as packing materials inside the interface of the online coupling between RPLC and GC is proposed for the enantiomeric analysis of β‐pinene and limonene in essential oils. For that purpose, a comparison of the RSD, detection limit and recovery provided by two absorbents and one adsorbent is included in this study. The results found in this work proved the validity of absorbents as packing materials in online RPLC–GC to determine minor compounds in complex matrices. In particular, PDMS seemed to be specially useful to analyse nonpolar compounds, such as β‐pinene and limonene, since it provided higher sensitivity for this kind of compounds. The developed method was applied to the evaluation of the natural and non‐natural character of commercial essential oils by means of the determination of the enantiomeric composition of β‐pinene and limonene.

A polymeric material commonly used as a superabsorbent in the sanitary industry is proposed for the first time for analytical purposes. Specifically, we have evaluated in this work the possibility of using this material in a programmed‐temperature vaporizer (PTV) injector for the introduction of large volume samples. To that end, the viability of this superabsorbent polymer as a retaining material was first studied by testing the stability of its absorption capacity in the presence of various solvents and at various temperatures. Subsequently, its effectiveness in the isolation of menthol and its isomers fromMentha piperitaessential oil as well as γ‐lactones from peach essential oil was assessed. For that purpose, optimization of different variables, namely PTV temperatures during sampling, purge times, and desorption temperatures, involved in the solvent elimination was performed. Additionally, the information obtained was compared with that acquired for the adsorbent material Tenax TA. The results shown in this work proved not only the viability of using this superabsorbent polymer in analytical procedures but also demonstrated its advantages over the adsorbent Tenax TA in attaining internal GC concentration of a sample by introducing large volumes via PTV.

Characteristic aroma compounds in plants and essential oils of Lavandula from different varieties were examined. The study of the qualitative and quantitative composition of the major volatile components was faced by developing a method based on the use of supercritical fluid extraction‐GC‐MS (SFE‐GC‐MS). The optimization of a variety of parameters affecting SFE extraction enabled RSDs from three replicates lower than 2% to be achieved. Equally, recoveries of up to 59% were obtained by applying the proposed method. The use of multidimensional GC was necessary to enantiomerically resolve the target compounds. The obtained results showed enantiomeric purities >90% for all studied compounds in all varieties considered, proving the natural invariability of the enantiomeric composition of the compounds of interest. This information can be useful in authenticity studies as well as in selecting natural sources of enantiomerically pure compounds.