Search Results (5)

Hydrolates are aromatic aqueous solutions saturated with volatile water-soluble compounds of essential oil. Despite their potential, hydrolates remain less explored than essential oils. In this work, the hydrolate of Pelargonium odoratissimum (L.) L’Hér. has been analyzed by multiple analytical techniques in order to describe its chemical composition. Headspace (HS-) and Direct Immersion-Solid Phase Microextraction-Gas Chromatography/Mass spectrometry (DI-SPME-GC/MS) and Proton Transfer Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS) were employed to reveal the VOC emission from the hydrolate. Further, a direct injection of the pure hydrolate and of the hydrolate after extraction with hexane was performed by Large-Volume Injection Gas Chromatography/Mass Spectrometry (LVI-GC/MS) and GC/MS. The results obtained by HS- and DI-SPME-GC/MS highlighted a nearly overlapping chemical profile with linalool, isomenthone, and α-terpineol as the main volatiles. On the other hand, analysis of the hydrolate by GC/MS after solvent extraction revealed a lower overall number of compounds but allowed the detection of thujone and cis-linalool oxide. In comparison, LVI-GC/MS was the technique that allowed the identification of a higher number of volatiles with citronellol, linalool, and α-terpineol as the principal compounds. Finally, PTR-ToF-MS was a fundamental approach to quantify and evaluate total terpene emissions from this complex matrix starting from low-molecular-weight compounds such as acetylene, methanol, acetaldehyde, acetone, and ethanol, which were the most abundant. Among the detected compounds, dimethyl sulfide and small amounts of dimethyl-furan and 2-butylfuran were also identified. Overall, the findings showed that the hydrolate was rich in monoterpene compounds while sesquiterpene compounds were missing. A very low intensity relating to sesquiterpenes was recorded only by PTR-ToF-MS technique. Full article

Cannabis sativa L. is a plant that has been cultivated since ancient times thanks to its various uses. Even its extraction products, such as essential oil and hydrolate, having a varied chemical composition and rich in bioactive components, find wide use in different sectors, gathering ever-increasing interest over time. In this work, the essential oil of Cannabis sativa L. cv. Carmagnola was characterized by using Gas Chromatography/Mass Spectrometry (GC/MS) and, for the first time, the chemical profile of the hydrolate was also described through different analytical techniques such as Large-Volume Injection Gas Chromatography/Mass Spectrometry (LVI-GC/MS) and Direct Immersion-Solid Phase Microextraction-Gas Chromatography/Mass spectrometry (DI-SPME-GC/MS), in order to provide a more complete compositional profile. The results of the analyses conducted on the hydrolate highlighted a high content of α-terpineol; on the other side, in the essential oil, a prevalence of monoterpenes, with α-pinene and limonene as the characterizing components, was detected. Both matrices were also investigated to evaluate their cytotoxic activity by using a panel of cancer cell lines derived from different histotypes such as melanoma (A375, LOX IMVI), non-small cell lung cancer (H1299, A549), colon (HT29) and pancreatic (L3.6) cancer cell lines. The obtained data demonstrated that essential oil was more effective than hydrolate in terms of reduction in cell viability. Full article

This work entailed the development, optimization, validation, and application of a novel analytical approach, using the bar adsorptive microextraction technique (BAμE), for the determination of the six most common tricyclic antidepressants (TCAs; amitriptyline, mianserin, trimipramine, imipramine, mirtazapine and dosulepin) in urine matrices. To achieve this goal, we employed, for the first time, new generation microextraction devices coated with convenient sorbent phases, polymers and novel activated carbons prepared from biomaterial waste, in combination with large-volume-injection gas chromatography-mass spectrometry operating in selected-ion monitoring mode (LVI-GC-MS(SIM)). Preliminary assays on sorbent coatings, showed that the polymeric phases present a much more effective performance, as the tested biosorbents exhibited low efficiency for application in microextraction techniques. By using BAμE coated with C₁₈ polymer, under optimized experimental conditions, the detection limits achieved for the six TCAs ranged from 0.2 to 1.6 μg L⁻¹ and, weighted linear regressions resulted in remarkable linearity (r² > 0.9960) between 10.0 and 1000.0 μg L⁻¹. The developed analytical methodology (BAμE(C18)/LVI-GC-MS(SIM)) provided suitable matrix effects (90.2–112.9%, RSD ≤ 13.9%), high recovery yields (92.3–111.5%, RSD ≤ 12.3%) and a remarkable overall process efficiency (ranging from 84.9% to 124.3%, RSD ≤ 13.9%). The developed and validated methodology was successfully applied for screening the six TCAs in real urine matrices. The proposed analytical methodology proved to be an eco-user-friendly approach to monitor trace levels of TCAs in complex urine matrices and an outstanding analytical alternative in comparison with other microextraction-based techniques. Full article

To determine the amount of the explosives 1,3-dinitrobenzene, 2,4-dinitrotoluene, 2,4,6-trinitrotoluene, and its metabolites in marine samples, a toolbox of methods was developed to enhance sample preparation and analysis of various types of marine samples, such as water, sediment, and different kinds of biota. To achieve this, established methods were adapted, improved, and combined. As a result, if explosive concentrations in sediment or mussel samples are greater than 10 ng per g, direct extraction allows for time-saving sample preparation; if concentrations are below 10 ng per g, techniques such as freeze-drying, ultrasonic, and solid-phase extraction can help to detect even picogram amounts. Two different GC-MS/MS methods were developed to enable the detection of these explosives in femtogram per microliter. With a splitless injector, limits of detection (LODs) between 77 and 333 fg/µL could be achieved in only 6.25 min. With the 5 µL programmable temperature vaporization—large volume method (PTV-LVI), LODs between 8 and 47 fg/µL could be achieved in less than 7 min. The detection limits achieved by these methods are among the lowest published to date. Their reliability has been tested and confirmed by measuring large and diverse sample sets. Full article

We developed, optimized and validated a fast analytical cycle using high throughput bar adsorptive microextraction and microliquid desorption (HT-BAμE-μLD) for the extraction and desorption of ketamine and norketamine in up to 100 urine samples simultaneously, resulting in an assay time of only 0.45 min/sample. The identification and quantification were carried out using large volume injection-gas chromatography-mass spectrometry operating in the selected ion monitoring mode (LVI-GC-MS(SIM)). Several parameters that could influencing HT-BAµE were assayed and optimized in order to maximize the recovery yields of ketamine and norketamine from aqueous media. These included sorbent selectivity, desorption solvent and time, as well as shaking rate, microextraction time, matrix pH, ionic strength and polarity. Under optimized experimental conditions, suitable sensitivity (1.0 μg L⁻¹), accuracy (85.5–112.1%), precision (≤15%) and recovery yields (84.9–105.0%) were achieved. Compared to existing methods, the herein described analytical cycle is much faster, environmentally friendly and cost-effective for the quantification of ketamine and norketamine in urine samples. To our knowledge, this is the first work that employs a high throughput based microextraction approach for the simultaneous extraction and subsequent desorption of ketamine and norketamine in up to 100 urine samples simultaneously. Full article