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Background: Polycyclic aromatic hydrocarbons (PAHs) represent a diverse group of organic compounds characterized by the fusion of two or more benzene rings arranged in various structural forms. Due to their harmful effects on human health, it is essential to implement monitoring systems and preventive measures to regulate human exposure. Given the affinity of PAHs for lipids, extensive research has been focused on their presence in vegetable oils. This study aimed to develop an on-line liquid-gas chromatography (LC-GC) method (using tandem mass spectrometry) with minimized solvent consumption for the determination of 16 PAHs in extra-virgin olive oil (EVOO)., Results: A side-by-side comparison of the selected-ion-monitoring and the pseudo multiple-reaction-monitoring (p-MRM) acquisition modes was performed, in terms of specificity and detectability. The results obtained using the p-MRM mode were superior, and for this reason it was selected. The method was linear over the concentration range 1-200 μg kg -1 (except in five cases, over 2-200 and 5-200 μg kg -1 ranges). Accuracy (at the 2 μg kg -1 and 20 μg kg -1 concentration levels) was in the 86.9-109.3 % range, with an RSD <10 %. Intra-day and inter-day precision (at 2 μg kg -1 and 20 μg kg -1 concentration levels) were in the 1.2-9.7 % and 3.2-10.8 % ranges, respectively. For all the PAHs, a negative matrix effect was observed. Three out of sixteen PAHs were detected in three EVOOs (among ten samples), albeit at the low ppb level. Limits of quantification were satisfactory in relation to EU legislation on the presence of PAHs in vegetable oils., Significance: A dilute-and-inject LC-GC-tandem mass spectrometry method is herein proposed fulfilling EU legislation requirements; sample preparation was very simple, inasmuch that it involved only a dilution step, thus avoiding extraction, clean-up, and thus a high consumption of organic solvents. In fact, considering both oil dilution and the LC mobile phase, less than 8 mL of solvents were used., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Mariosimone Zoccali reports financial support was provided by Ministry of University and Research. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Omics is used as an analytical tool to investigate wine authenticity issues. Aging authentication ensures that the wine has undergone the necessary maturation and developed its desired organoleptic characteristics. Considering that aged wines constitute valuable commodities, the development of advanced omics techniques that guarantee aging authenticity and prevent fraud is essential., Results: Α solid phase microextraction Arrow method combined with comprehensive two-dimensional gas chromatography-mass spectrometry was developed to identify volatiles in red wines and investigate how aging affects their volatile fingerprint. The method was optimized by examining the critical parameters that affect the solid phase microextraction Arrow extraction (stirring rate, extraction time) process. Under optimized conditions, extraction took place within 45 min under stirring at 1000 rpm. In all, 24 monovarietal red wine samples belonging to the Xinomavro variety from Naoussa (Imathia regional unit of Macedonia, Greece) produced during four different vintage years (1998, 2005, 2008 and 2015) were analyzed. Overall, 237 volatile compounds were tentatively identified and were treated with chemometric tools. Four major groups, one for each vintage year were revealed using the Hierarchical Clustering Analysis. The first two Principal Components of Principal Component Analysis explained 86.1% of the total variance, showing appropriate grouping of the wine samples produced in the same crop year. A two-way orthogonal partial least square - discriminant analysis model was developed and successfully classified all the samples to the proper class according to the vintage age, establishing 17 volatile markers as the most important features responsible for the classification, with an explained total variance of 88.5%. The developed prediction model was validated and the analyzed samples were classified with 100% accuracy according to the vintage age, based on their volatile fingerprint., Significance: The developed methodology in combination with chemometric techniques allows to trace back and confirm the vintage year, and is proposed as a novel authenticity tool which opens completely new and hitherto unexplored possibilities for wine authenticity testing and confirmation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This preliminary research is focused on the task of defining an equivalent standard column set between cryogenic and flow-modulation comprehensive two-dimensional gas chromatography (GC × GC) combined with mass spectrometry (MS). Cryogenic modulation (CM) was carried out by using a loop-type device, while the flow modulator used was a seven-port wafer chip, equipped with an external accumulation loop. Initially, a common low-polarity + mid-polarity CM GC × GC column set was selected (30 m × 0.25 mm ID × 0.25 μm d f  + 1.5 m × 0.25 mm ID × 0.25 μm d f ), a method was developed, and a GC × GC-MS fingerprint was attained (on a sample of bio-oil derived from coconut fibers). After, a column set with the same stationary phases was selected for the flow modulation GC × GC-MS method (20 m × 0.18 mm ID × 0.18 μm d f  + 5 m × 0.32 mm ID × 0.25 μm d f ), with the capability to provide a-similar-as-possible separation. A side-by-side measurement of several chromatography parameters (efficiency, peak capacity, resolution, peak widths, retention factors, elution temperatures) was made., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

An on-line liquid chromatography-comprehensive two-dimensional gas chromatography (LC-GC×GC) separation process, combined with a dual detection system, namely triple quadrupole mass spectrometry (used as a single quadrupole - QMS) and flame ionization detection (FID), was developed for the analysis of cosmetic lip care products. The LC step was carried out by using a fused-core silica column, with this enabling the separation of mineral oil saturated hydrocarbons (MOSH), as well as polyolefin oligomeric saturated hydrocarbons (POSH), from the mineral oil aromatic hydrocarbon (MOAH) families. Each chemical class was then subjected to GC×GC-QMS/FID analysis, using a medium polarity-low polarity column combination. Notwithstanding the utility of the flame ionization detector for quantification purposes, it is obviously also desirable to obtain information on the type of hydrocarbons present (of mineral or synthetic origin), in order to identify a potential contamination source. Following method optimization, various analytical figures of merit (method linearity, intra- and inter-day repeatability, limits of detection and quantification, and injector discrimination) were measured. Specifically, for MOSH and MOAH, linearities were evaluated in the 32.5-2080 and 50-500 mg L -1 range, respectively; furthermore, intra- and inter-day repeatability values were 6.2 and 8.3%, respectively, while limits of detection and quantification were 3.5 and 11.8 mg L -1 , respectively. The proposed method, enables for the first time (to the best of the authors' knowledge), the detailed qualitative and quantitative analysis of saturated and aromatic hydrocarbons, in a single run and in a fully-automated manner. Quantities of MOSH + POSH in the cosmetic products ranged from 8.7 to 44.4% (CV values were in the 1.5-5.4% range) while MOAH contamination was found in four samples, ranging from 386 to 5869 mg kg -1  (CV values were in the 0.5-4.5% range)., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A direct on-line method based on the coupling of supercritical fluid extraction and supercritical fluid chromatography with triple quadrupole mass spectrometry detection (SFE-SFC-QqQ/MS) for selected carotenoids determination and apocarotenoids detection in intact human blood was developed for the first time. Carotenoids and apocarotenoids were identified by using the available standard together with full scan, selected ion monitoring (SIM), and multiple reaction monitoring (MRM) experiments. Moreover, β-Cryptoxanthin, Zeaxanthin, β-Carotene and Capsanthin were directly quantified by the developed methodology, using a multiple reaction monitoring (MRM) approach; the determined average content of β-carotene was 123.8 nmol L -1 (range 18.7-485.1 nmol L -1 ), of β-cryptoxanthin was 385.3 nmol L -1 (range 72.5-1920.3 nmol L -1 ), of zeaxanthin was 396.9 nmol L -1 (range < LoD - 1795.8 nmol L -1 ) and of capsanthin was 38.9 nmol L -1 (range < LoD - 188.4 nmol L -1 ). Analyses were carried out on 10 μL aliquots of intact blood samples without any preliminary treatment; the online extraction and chromatographic separation time was just over 20 min. The method was validated in terms of linearity, precision, limits of detection and quantification, and accuracy. Interestingly, β-apo-12'-carotenal, apo-10'-zeaxanthinal, apo-12'-zeaxanthinal, apo-14'-zeaxanthinal, ε-apo-8-luteinal, ε-apo-12-luteinal and ε-apo-14-luteinal were detected in human blood, together with two zeaxanthin fatty acid esters, for the first time., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Phthalates are a group of synthetic compounds mainly used as plasticizers, which have been classified as endocrine-disrupting chemicals and potential human-cancer causing agents. They can be found in high amounts in foods, deriving mainly from plastic packaging. The analytical determination of these compounds is very challenging since they are ubiquitous. Therefore, minimization of sample manipulation is highly desirable. The present work exploited the application of a solid-phase microextraction method for the analysis of phthalates in vegetable oil. A preliminary comparison between a polydimethylsiloxane (PDMS) and a Carbopack Z/PDMS fiber was carried out both in the headspace and direct immersion extraction modes. Before immersing the fiber, a rapid liquid-liquid extraction was performed using acetonitrile to remove the bulk of triglycerides. PDMS in the direct immersion mode showed the best performance. The method was fully validated obtaining a good linearity with a coefficient of correlation of over 0.9960 for all compounds, repeatability and accuracy values generally better than 10%, and very good limit of quantification values., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The fatty acids (FAs) composition of lipids extracted from Rhodobacter sphaeroides 2.4.1 was investigated by gas chromatography-mass spectrometry (GC-MS) analysis of the corresponding FA methyl esters (FAMEs), obtained through trans-esterification of the original lipid species. A GC stationary phase based on a highly polar ionic liquid (IL) was selected, aimed to enhance the separation of isomeric FAMEs with particular emphasis on positional and geometrical isomers of monounsaturated 16:1 and 18:1 fatty acyl chains. The occurrence of 18:1 cis-Δ(9) (oleic) acid, a positional isomer of the well-known and most predominant 18:1 cis-Δ(11) (cis-vaccenic) acid, has been demonstrated here for the first time. Furthermore a methyl branched 18:1 FA was also identified and its structure tentatively assigned as 11-methyl-Δ(12)-octadecenoic acid (most likely as trans isomer). The unprecedented observation about 18:1 cis-Δ(9) FA occurrence in R. sphaeroides 2.4.1 is, even indirectly, supported by a biosynthetic pathway postulated with the aid of the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The concurrent presence of 16:1 cis-Δ(7) and 18:1 cis-Δ(9) FAs suggested the existence of parallel and/or complementary processes to those invoked for the formation of most common 16:1 cis-Δ(9) and 18:1 cis-Δ(11) FAs. A further route was hypothesized for the trans FAs biosynthesis in wild-type cells of R. sphaeroides., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Objective: of this work was to develop suitable extraction methodologies for the isolation of lipids from fish, mussels and clams from the Mediterranean sea, and their successive analysis by means of advanced chromatographic instrumentation. More specifically, three different sample preparation methodologies were adopted: Folch's, Bligh & Dyer's and maceration. The lipidic extracts, after application of two different methylation procedures, were subjected to monodimensional and comprehensive two-dimensional GC analyses, in order to compare the fingerprints of samples derived from different extraction and transesterification methodologies. Triacylglycerols (TAGs) were analyzed by an off-line combination of silver-ion liquid chromatography with non-aqueous reversed phase liquid chromatography. In both LC and GC analyses, mass spectrometric detectors were used, which greatly supported the identification procedure. In particular, with respect to HPLC, mass spectrometry with atmospheric pressure chemical ionization in positive mode was applied., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The present research reports the use of a three-dimensional preparative gas chromatography (prep GC) system, equipped with three Deans-switch devices and 5%diphenyl/wax/mid-polarity ionic liquid stationary phases, for the isolation of volatile components from a complex natural source, namely wampee essential oil (derived from Clausena lansium Skeels leaves). Collection was performed by using a simple and effective lab-constructed trapping device. Initially, an unknown (and abundant) wampee oil constituent was erroneously identified as α-sinensal, through an MS database search (a low similarity match was attained), performed after a GC-quadMS experiment., The unknown compound was then the isolated by using the novel prep GC system, in a highly pure form (at the mg level), and was correctly identified by using nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR) and mass spectrometry (MS). Both FTIR and MS data were used to confirm the NMR information. The name given to the molecule was (2E,6E)-2-methyl-6-(4-methylcyclohex-3-enylidene)hept-2-enal. The results herein described will demonstrate the need for a high-resolution GC step, prior to analyte collection, in the prep GC analysis of complex samples., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The present work is focused on the development/optimization of a comprehensive two-dimensional gas chromatography method, with dual detection [flame ionization (FID) and mass spectrometric], for the simultaneous identification and quantification of mineral-oil contaminants in a variety of food products. The two main classes of contaminants, namely saturated and aromatic hydrocarbons, were previously fractionated on a manually-packed silver silica solid-phase extraction (SPE) cartridge. The quantitative results were compared with those obtained by performing a large volume injection, in a GC-FID system, after the same SPE process and by an on-line liquid-gas chromatography method, with very similar results observed. The presence of a series of unknown compounds, that appeared when using the off-line methods, was investigated using the mass spectrometric data, and were tentatively-identified as esterified fatty acids, most probably derived from vegetable oil based ink., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Multiple headspace-solid phase microextraction (MHS-SPME) followed by gas chromatography/mass spectrometry (GC-MS) and flame ionization detection (GC-FID) was applied to the identification and quantification of volatiles released by the mushroom Agaricus bisporus, also known as champignon. MHS-SPME allows to perform quantitative analysis of volatiles from solid matrices, free of matrix interferences. Samples analyzed were fresh mushrooms (chopped and homogenized) and mushroom-containing food dressings. 1-Octen-3-ol, 3-octanol, 3-octanone, 1-octen-3-one and benzaldehyde were common constituents of the samples analyzed. Method performance has been tested through the evaluation of limit of detection (LoD, range 0.033-0.078 ng), limit of quantification (LoQ, range 0.111-0.259 ng) and analyte recovery (92.3-108.5%). The results obtained showed quantitative differences among the samples, which can be attributed to critical factors, such as the degree of cell damage upon sample preparation, that are here discussed. Considerations on the mushrooms biochemistry and on the basic principles of MHS analysis are also presented., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The present contribution is focused on the main advances made in the field of heart-cutting multidimensional gas chromatography (MDGC), over approximately the last decade. Brief details on the history of classical MDGC are also given. A series of applications, carried out with modern-day commercially available instrumentation are shown, demonstrating the usefulness of the bidimensional methodology in specific analytical situations. Finally, the future prospects of MDGC are considered, within the shadow projected by a very powerful GC technique, namely comprehensive two-dimensional gas chromatography., (Copyright © 2011 Elsevier B.V. All rights reserved.)