Identifying Putative Biomarkers of Foodborne Pathogens Using a Metabolomic Approach.

Metabolomics is the study of low molecular weight biochemical molecules (typically <1500 Da) in a defined biological organism or system. In case of food systems, the term "food metabolomics" is often used. Food metabolomics has been widely explored and applied in various fields including food analysis, food intake, food traceability, and food safety. Food safety applications focusing on the identification of pathogen-specific biomarkers have been promising. This chapter describes a nontargeted metabolite profiling workflow using gas chromatography coupled with mass spectrometry (GC-MS) for characterizing three globally important foodborne pathogens, Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica, from selective enrichment liquid culture media. The workflow involves a detailed description of food spiking experiments followed by procedures for the extraction of polar metabolites from media, the analysis of the extracts using GC-MS, and finally chemometric data analysis using univariate and multivariate statistical tools to identify potential pathogen-specific biomarkers.

Metabolomics of Chinese Hamster Ovary Cells.

Increasing demand of protein biotherapeutics produced using Chinese hamster ovary (CHO) cell lines necessitates improvement in the production yield of the bioprocess. Various cell engineering, improved media formulation and process-design based approaches utilizing the power of OMICS technologies, specifically, genomics and proteomics, have been employed; however, the potential of metabolomics largely remains unexplored. Metabolomics enables the detection, identification, and/or quantitation of small molecules, commonly known as metabolites, in and around the cells and may help to unlock the cellular molecular mechanism(s) that regulates cell growth and productivity in the bioprocess and improves cellular performance during the bioprocess. Currently, liquid chromatography (LC)/gas chromatography (CG)- coupled with mass-spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy are the most commonly used approaches for metabolomics. Therefore, in this chapter, we have discussed the standard procedures of investigating CHO metabolites using LC/GC-MS and/or NMR-based approaches.

Development of a green microextraction procedure for determining polyaromatic hydrocarbons in electronic equipment plastics.

The global proliferation of electronic devices, driven by technological advancements, has led to the release of organic pollutants from the plastic components of these devices, particularly in indoor environments. Among these pollutants, polycyclic aromatic hydrocarbons (PAHs), which are emitted into the air from plastic components, play a critical role in the field of indoor environment pollution. Consequently, effectively monitoring the PAH content in plastics used in electronic equipment is crucial for preventing indoor contamination. In this study we aimed to develop a fast, inexpensive, easy, and environmentally friendly analysis method for determining PAH content in plastic equipment. A dispersive liquid liquid microextraction (DLLME) combined with solidified organic drop (SFO) microextraction technique was developed. Considering the eleven number of parameters that can affect the signal in the DLLME-SFO method, Plackett Burmann's design was applied to select the most three impactful parameters for 18 PAH species. A Box-Behnken experimental design was also applied to optimize the identified parameters. The optimal conditions for the most influential parameters such as solvent type, pH, and the sample weight were identified as 1-dodecanol, 12 and 0.24 g, respectively. The proposed method was validated under these optimized conditions, yielding low detection limits ranging from 0.004 to 0.11 ng mL-1. The calibration curves were linear with correlation coefficients above 0.98 and relative standard deviation (RSD) values ranging from 2.4% to 20%. This method was successfully applied to analyze PAH content in the plastic components of electronic devices. The extraction technique developed in this study is a newly developed technique and has not been previously used to analyze organic pollutants that may be present in electronic equipment plastic.

Evaluating the reliability of solid phase extraction techniques for hydrocarbon analysis by GC-MS.

Saturate and aromatic compounds are essential in the petroleum industry for assessing the thermal maturity of source rocks and oils, which is critical for basin modeling and sweet-spot mapping. These compounds also play a role in environmental applications, such as oil spill fingerprinting and biogeochemistry. However, the analysis of these compounds by gas chromatography-mass spectrometry (GC-MS) requires meticulous and time-consuming separation processes. Traditional methods like normal-phase liquid column chromatography (LCC) involve large volumes of harmful solvents. This study evaluates the effectiveness of five different sorbents using solid-phase extraction (SPE) techniques-neutral Si, SiOH, Ag-ion, neutral Al, and Ag-ion mixed with activated silica-compared to LCC. The goal was to discern differences in peak resolution, concentration, and isomer ratios of saturate and aromatic compounds for thermal maturity and source rock assessments. The results show that SiOH, neutral Si, and neutral Al do not fully separate aromatic compounds from the saturate fraction, sometimes leaving 40-100% of aromatics within the saturate fraction. Ag-ion mixed with activated silica provided the best separation, resulting in up to 23 times higher aromatic concentration than SiOH. This method is more reliable for quantifying both saturate and aromatic compounds, increases the efficiency of hydrocarbon evaluations, and reduces solvent consumption by 63%, offering a more sustainable approach to hydrocarbon analysis.

Evaluating the detection of barbiturates in dried blood spots: A comparative analysis using gas chromatography-mass spectrometry, gas chromatography-tandem mass spectrometry, and liquid chromatography-tandem mass spectrometry with different extraction methods.

Rapid and accurate characterization and quantitation of blood barbiturates and their combination drugs are very important for the clinical treatment of acute barbiturate poisoning. A comparison of dried blood spot (DBS) and traditional liquid-liquid extraction (LLE) in the pre-treatment stage, as well as a comparison of gas chromatography-mass spectrometry (GC-MS), gas chromatography-tandem mass spectrometry (GC-MS/MS), and liquid chromatography-tandem mass spectrometry (LC-MS/MS) as instrumental analysis methods, revealed differences in the analysis results of barbiturates and their combination drugs under different conditions. Based on these findings, we introduce a DBS-GC-MS/MS method. The developed and validated method showed good selectivity, sensitivity (LOD: 0.1 µg mL-1, LOQ: 0.2 µg mL-1), linearity (R2>0.9992), trueness (<15 %, except for carbamazepine, at 29.4 %), and precision (<15 %). Recovery was also good for most target compounds, but significant matrix effects were evident. Compared with the LLE method, the DBS method has the benefits of easy sample collection, storage, and transport, as well as simple pre-treatment and reduced reagent and energy consumption. Compared to LC-MS/MS, GC-MS/MS requires no switching between positive and negative ion modes and uses the MRM detection mode, meaning that more information about the sample compounds can be obtained in less analysis time. Using actual sample analysis, we have demonstrated the advantages of the DBS-GC-MS/MS method for the qualitative and quantitative analysis of barbiturates and poisoning events due to combinations of these drugs. Comparison of the three instruments and the two treatment methods revealed their analysis characteristics. From the perspective of practical application, the broad practical value and advantages of DBS should be embraced in more applications, and future analytical laboratory development should continue to recognize GC-MS/MS as a useful supplement to LC-MS/MS.

In Vitro Antibacterial Activity of Adiantum capillus Veneris Extraction with Methanol, Chloroform, and Ether Solvents against Methicillin-resistant Staphylococcus aureus.

BACKGROUND: The increasing problem of multi-drug resistant (MDR) pathogens is a worldwide concern, especially in the pharmaceutical industry. At the same time, medicinal plants have renewed interest because of their wide variety of bioactive phytochemicals, which could be used to develop new antimicrobial drugs. This renewed interest is partly due to the growing resistance to traditional drugs and their associated side effects. METHODS: The objective of this study is to assess the antimicrobial properties of the total extract and various fractions of Adiantum capillus veneris against Methicillin-resistant Staphylococcus aureus (MRSA). The aerial parts of Adiantum capillus veneris were subjected to extraction using methanol, chloroform, and ether, and the resulting extracts were tested for their antimicrobial activity against MRSA. Additionally, essential oil was obtained from the aerial parts using a Clevenger apparatus and boiling water. Furthermore, Gas Chromatography-Mass Spectrometry (GC/MS) was utilized to analyze the phytochemicals isolated from the extracts of Adiantum capillus veneris. RESULTS: The essential oil was obtained through distillation and then analyzed using GC/MS. The antimicrobial activity was evaluated using the agar diffusion method. CONCLUSION: GC/MS analysis revealed that the composition was primarily phytol (59.9%), constituting 99.3% of phyto-constituents. However, both the total extract and the individual fractions exhibited no inhibitory effects against MRSA strains.

Research on the Mechanism of Growth of Codonopsis pilosula (Franch.) Nannf. Root Responding to Phenolic Stress Induced by Benzoic Acid.

Soil autotoxic chemosensory substances have emerged as the predominant environmental factors constraining the growth, quality, and yield of Codonopsis pilosula in recent years. Among a vast array of chemosensory substances, benzoic acid constitutes the principal chemosensory substance in the successive cultivation of C. pilosula. However, the exploration regarding the stress exerted by benzoic acid on the growth and development of C. pilosula remains indistinct, and there is a scarcity of research on the mechanism of lobetyolin synthesis in C. pilosula. In the current research, it was discovered that exposure to benzoic acid at a concentration of 200 mmol/L conspicuously attenuated the plant height, root length, total length, fresh weight, root weight, root thickness, chlorophyll content, electrolyte osmolality, leaf intercellular CO2 concentration (Ci), net photosynthesis rate (Pn), transpiration rate (Tr), and leaf stomatal conductance (Gs) of C. pilosula. Benzoic acid (200 mmol/L) significantly enhanced the activity of root enzymes, including superoxide dismutase (SOD), malondialdehyde (MDA), and peroxidase (POD), as well as the accumulation of polysaccharides and lobetyolins (polyacetylene glycosides) in the roots of C. pilosula. In this study, 58,563 genes were assembled, and 7946 differentially expressed genes were discovered, including 4068 upregulated genes and 3878 downregulated genes. The outcomes of the histological examination demonstrated that benzoic acid stress augmented the upregulation of genes encoding key enzymes implicated in the citric acid cycle, fatty acid metabolism, as well as starch and sucrose metabolic pathways. The results of this investigation indicated that a moderate amount of benzoic acid could enhance the content of lobetyolin in C. pilosula and upregulate the expression of key coding genes within the signaling cascade to improve the resilience of C. pilosula lobetyolin against benzoic acid stress; this furnished a novel perspective for the study of C. pilosula lobetyolin as a potential substance for alleviating benzoic acid-induced stress.

Evaluation of Volatile Organic Compounds from Spotted Lanternfly (Lycorma delicatula) Eggs Using Headspace Odor Sampling Methods.

The spotted lanternfly (SLF) is an invasive species native to China. It was first discovered in the United States in Pennsylvania in 2014. It is known to cause great economic damage by destroying various crops, specifically grape vines, and therefore, several efforts have been made to control and mitigate its spread from the Northeast. Canine detection is a useful detection tool; however, it is crucial to understand the volatile organic compounds emitting by this pest to better direct canine training paradigms to prevent false alerts and to understand potential volatile markers of importance indicative of this species. The purpose of this study is to address the gap in research regarding the volatile organic compound (VOC) profile of SLF to better inform pest control mitigation strategies. Instrumental analysis was performed utilizing SPME-GC/MS on cold-killed SLF eggs, dried crickets, and tree bark. Differences in detected VOCs within each sample set depicted distinctive odor profiles for each matrix tested. Storage of these samples also depicted VOC accumulation variation as a function of time, thereby providing implications for long-term storage and sample handling for these types of training aids in canine applications.

[Determination of multiple restricted and prohibited ingredients in hair dyes using a novel 3D stationary phase coupled with gas chromatography-mass spectrometry].

Hair dyes (HDs) are mainly composed of various benzene series, amines, and phenolic compounds. These ingredients are well known to have allergenic, teratogenic, and carcinogenic properties. As such, the presence of these ingredients in HDs has received increased attention in recent years. At present, the applications of traditional analytical and detection methods and commercial chromatographic columns are limited by problems such as poor qualitative analysis and inaccurate quantification. Thus, the development of new analytical and detection technologies and stationary phases is an urgent endeavor. Moreover, HDs contain complex compounds and exhibit significant matrix interference. Hence, appropriate sample pretreatment methods are necessary to analyze HDs. In this study, the 3D nonpolar rigid structure of triptycene (TP) was combined with the polar flexible chains of polyethylene glycol (PEG) to design and synthesize a TP derivative, TP-PEG, as a stationary phase for chromatographic columns. The stationary phase enabled the expansion of the selection range for polar and nonpolar analytes. Subsequently, gas chromatography-mass spectrometry (GC-MS) was used to quantitatively analyze 22 ingredients in HDs. The experimental results demonstrated that analytes with different polarities exhibited sharp and symmetrical peak shapes on the stationary phase, and all 22 analytes achieved baseline separation on the chromatographic column. The 22 ingredients in HDs showed good linear relationships within their respective ranges, with correlation coefficients greater than 0.9985. The average recovery rates at three spiked levels were in the range of 89.2%-103.2%, and RSDs were less than 5%. Compared with traditional methods, the proposed method has higher efficiency and better accuracy, thus verifying the excellent separation performance of the new stationary phase and the effectiveness of the established GC-MS detection method. The findings indicated the applicability of the developed method to the detection and analysis of various compounds in HDs.

The optimization and validation of a gas chromatography-mass spectrometry method to analyze the concentration of acetate, propionate and butyrate in human plasma or serum.

Fermentation-derived short-chain fatty acids (SCFA)4 are potential mediators of the health benefits associated with dietary fiber intake. SCFA affect physiological processes locally in the gut and on distant organs via the systemic circulation. Since SCFA are used as energy source for colonocytes and substrate for the liver metabolism, their concentrations in the systemic circulation are low. Therefore, quantification of systemic SCFA requires sensitive analytical techniques. This article covers the optimization and validation of a gas chromatography-mass spectrometry method to measure systemic SCFA concentrations following derivatization with 2,4-difluoroaniline (DFA)5 and extraction in ethyl acetate. Sample preparation was optimized by varying the amount of DFA, coupling agent 1,3-dicyclohexylcarbodiimide, ethyl acetate and sodium bicarbonate, which is used to quench derivatization. In addition, evaporation of the samples using a vacuum concentrator resulted in less contamination, notably of acetate, compared to drying with N2 gas. The method showed excellent linearity with coefficient of variation (R2) > 0.99 and a good precision (relative standard deviation < 20 %) and accuracy. Finally, systemic concentrations of SCFA in human plasma samples could successfully be determined.

Effects of Broth pH and Chilling Storage on the Changes in Volatile Profiles of Boiled Chicken Flesh.

This study investigated the changes in volatile compounds in chicken flesh after boiling at various pHs (6.0-9.0) and after chilling storage (4.0±1.0°C) for 7 d. The volatile compounds were assessed qualitatively and quantitatively by using a headspace gas chromatography-mass spectrometry analysis. Twenty-one volatile compounds were discovered and categorized as amine, aldehyde, alcohol, ketone, acid, and furan. One type of amine, (2-aziridinylethyl) amine, was the most prevalent volatile component, followed by aldehyde, ketone, aldehyde, acid, ester, and furan. The results showed that the quantity and quality of the volatile compounds were influenced by a pH of the boiling medium. Additionally, the types and volatile profiles of the chicken were altered during chilling. In particular, in the chicken that was boiled at a pH of 8.0, the hexanal (an aldehyde) content increased the most after 7 d of chilling. Moreover, various alcohols formed after the 7 d of chilling of the chicken that was boiled at pHs of 8.0 and 9.0. Because of the oxidation and degradation of fat and proteins, the most altering volatile compounds were the reducing amines and the increasing aldehydes.

Determination of volatile organic compounds (VOCs) in indoor work environments by solid phase microextraction-gas chromatography-mass spectrometry.

Volatile organic compounds (VOCs) are continuously emitted into the atmosphere from natural and anthropogenic sources and rapidly spread from the atmosphere to different environments. A large group of VOCs has been included in the class of air pollutants; therefore, their determination and monitoring using reliable and sensitive analytical methods represents a key aspect of health risk assessment. In this work, an untargeted approach is proposed for the evaluation of the exposure to volatile organic compounds of workers in an engine manufacturing plant by GC-MS measurements, coupled with solid-phase microextraction (SPME). The analytical procedure was optimized in terms of SPME fiber, adsorption time, desorption time, and temperature gradient of the chromatographic run. For the microextraction of VOCs, the SPME fibers were exposed to the air in two different zones of the manufacturing factory, i.e., in the mixing painting chamber and the engine painting area. Moreover, the sampling was carried out with the painting system active and running (system on) and with the painting system switched off (system off). Overall, 212 compounds were identified, but only 17 were always present in both zones (mixing painting chamber and engine painting area), regardless of system conditions (on or off). Finally, a semi-quantitative evaluation was performed considering the peak area value of the potentially most toxic compounds by multivariate data analyses.

Flavoromic analysis of wines using gas chromatography, mass spectrometry and sensory techniques.

Various sensory perceptions drive the quality and typicality of wines, with the volatile profile playing a fundamental role in the characteristics of odor, aroma and consequently flavor, which combines the smell (odor and aroma), taste, and trigeminal sensations. Efforts have been made in both the field of instrumental and sensory analysis to understand the relationship of volatile compounds with sensory attributes in omics approaches. Gas chromatography (monodimensional and two-dimensional (heartcutting and comprehensive)) associated with mass spectrometry (GC/MS, GC-GC/MS and GCxGC/MS) and chemometric tools have contributed to foodomics analyses, specifically those linked to metabolomics/volatilomics. These tools, along with the elucidation of sensory properties (sensomics), lead to advanced results in the field of flavoromics. They also help to define the best practices in both vineyard management and winemaking that enable the production of high-quality wines. The objective of this review is to report the challenges of determining the volatile profile of wines, pointing out the ways that can be followed in successful identification and quantification of volatile compounds. The state of the art of sensory evaluation methods is also addressed, providing information that helps in choosing the most appropriate sensory method to be conducted with chromatographic analysis to achieve more in-depth results in the field of flavoromics.

[Analysis of phthalate esters from vegetable oils by gas chromatography-mass spectrometry coupled with headspace solid-phase microextraction using cyclodextrin-based hypercrosslinked polymer coated fiber].

Phthalate esters (PAEs) are used as additives to enhance the pliability and malleability of plastics. These substances frequently migrate from packaging materials to vegetable oils because of the absence of covalent bonds. Over time, this migration could result in the accumulation of PAEs in the human body through ingestion, contributing to various diseases. Therefore, accurate qualitative and quantitative analyses of PAEs in vegetable oils are imperative to assess the origins of contamination and investigate their toxicity, degradation, migration, and transformation patterns. However, the concentration of PAEs in most samples is low, and the composition of vegetable oils is complex. Thus, PAEs must be enriched and purified using appropriate sample pretreatment procedures before analysis. Common methods for pretreating PAEs in oil include solid-phase extraction (SPE), dispersive SPE, and magnetic SPE. These techniques require time-consuming and labor-intensive procedures such as oil dissolution, solvent extraction, and degreasing. These approaches also require numerous solvents and containers, increasing the risk of sample cross-contamination. Solid-phase microextraction (SPME) integrates sampling, extraction, purification, concentration, and injection into a single process, significantly accelerating analytical testing and reducing the potential for sample cross-contamination. In headspace (HS) mode, the analytes achieve equilibrium on the coating and are extracted in the gas phase. The fibers are shielded from nonvolatile and high-relative molecular mass substances in the sample matrix. Thus, SPME is an ideal method for extracting volatile compounds in vegetable oils. When HS-SPME coupled with gas chromatography-mass spectrometry (GC-MS), it can achieve the rapid screening of PAEs in vegetable oil. In this study, an SPME with cyclodextrin-based hypercrosslinked polymers (BnCD-HCP) coated on stainless steel fibers was employed to extract PAEs from vegetable oil. The structure and morphology of the polymers were characterized using Fourier-transform infrared spectroscopy, nuclear magnetic spectroscopy, and scanning electron microscopy. BnCD-HCP exhibited high stability and diverse interactions, including π-π, hydrophobic, and host-guest interactions. The oil samples were incubated with methanol, and the PAEs were extracted from the headspace using the probe. The optimal extraction parameters included an extraction time of 20 min, extraction temperature of 50 ℃, desorption time of 4 min, and desorption temperature of 275 ℃. The BnCD-HCP/HS-SPME method was evaluated under optimized experimental conditions. The limits of detection (LODs) and quantification (LOQs) were determined by applying signal-to-noise ratios (S/N) of 3 and 10, respectively. Method accuracy was evaluated using relative standard deviations (RSDs). Single-needle precision was evaluated by conducting three consecutive analyses at 3 h intervals within a day. Inter-needle precision was assessed by conducting the same analyses (three replicates) with differently coated fibers. The 12 PAE compounds exhibited good linearity with correlation coefficients (R2) of at least 0.99. The LODs and LOQs ranged from 0.21 to 3.74 µg/kg and from 0.69 to 12.34 µg/kg, respectively. The RSDs were in the range of 1.8%-11.4% and 5.1%-13.9% for the single-needle and needle-to-needle methods, respectively. The proposed method was applied to soybean, peanut, and sunflower oils, and two PAEs were found in all three oils. Moreover, the method demonstrated good precision (RSD=1.17%-11.73%) and recoveries (72.49%-124.43%). Compared with other methods, the developed method was able to extract many target analytes and had a low or comparable LOD and high recovery. More importantly, this method does not require tedious operations such as solvent extraction and purification. Consequently, the developed method can be used to extract not only PAEs in oils but also other substances with a high lipid content.

Innovative disposable in-tip cellulose paper (DICP) device for facile determination of pesticides in postmortem blood samples: A proof-of-concept study.

Accurately identifying and quantifying toxicants is crucial for medico-legal investigations in forensic toxicology; however, low analyte concentrations and the complex samples matrix make this work difficult. Therefore, a simplified sample preparation procedure is crucial to streamline the analysis to minimize sample handling errors, reduce cost and improve the overall efficiency of analysis of toxicants. To address these challenges, an innovative disposable in-tip cellulose paper (DICP) device has been developed for the extraction of three pesticides viz. Chlorpyrifos, Quinalphos and Carbofuran from postmortem blood samples. The DICP device leverages cellulose paper strips housed within a pipette tip to streamline the extraction process, significantly reducing solvent usage, time, and labor while maintaining high analytical accuracy. The extraction of pesticides from postmortem blood using the DICP device involves a streamlined process characterized by adsorption and desorption. The diluted blood samples were processed through the DICP device via repeated aspirating and dispensing calyces to adsorb the pesticides onto the cellulose paper. The adsorbed pesticides are then eluted using acetone, which is collected for GC-MS analysis. The method was meticulously optimized, achieving a limit of quantification in the range of 0.009-0.01 µg mL-1. The intra-day and inter-day precisions were consistently less than 5 % and 10 %, respectively, with accuracy ranging from 94-106 %. Relative recoveries for the analytes were observed to be between 60 % and 93.3 %, and matrix effects were determined to be less than 10 %. The method's sustainability was validated with a whiteness score of 98.8, an AGREE score of 0.64, a BAGI score of 70 and ComplexMoGAPI score of 77. Applicability was demonstrated through successful analysis of real postmortem blood samples and proficiency testing samples, highlighting its potential utility in forensic toxicology.

Mass spectrometry (MS)-based metabolomics of plasma and urine in dry eye disease (DED)-induced rat model.

Dry eye disease (DED) is an ophthalmic disease associated with poor quality and quantity of tears, and the number of patients is steadily increasing. The aim of this study was to determine plasma and urine metabolites obtained from DED scopolamine animal model where dry eye conditions (DRY) are induced. It was also of interest to examine whether DED (scopolamine) rat model was exacerbated by treatment with benzalkonium chloride (BAC). Subsequently, plasma and urine metabolites were analyzed using liquid chromatography (LC) and gas chromatography (GC)-mass spectrometry (MS), respectively. Data demonstrated that DED indicators such as tear volume, tear breakup time (TBUT), and corneal damage in the DED groups (DRY and BAC group) differed from those of control (CON). Similar results were noted in inflammatory factors such as interleukin (IL-1ß), IL-6, and tumor necrosis factor (TNF)-α. In the partial least squares-discriminant analysis (PLS-DA) score plots, the three groups were distinctly separated from each other. In addition, the related metabolites were also associated with these distinct separations as evidenced by 9 and 14 in plasma and urine, respectively. Almost all of the selected metabolites were decreased in the DRY group compared to CON, and the BAC group was lower than the DRY. In plasma and urine, lysophosphatidylcholine/lysophosphatidylethanolamine, organic acids, amino acids, and sugars varied between three groups, and these metabolites were related to inflammation and oxidative stress. Data suggest that treatment with scopolamine with/without BAC-induced DED and affected the level of systemic metabolites involved in inflammation and oxidative stress.

Discrepancies between the stated contents and analytical findings for electronic cigarette liquid products: Identification of the new cannabinoid, Δ9-tetrahydrocannabihexol acetate.

A number of synthetic cannabinoids have been appearing in the recreational drug market for more than a decade. Recent additions are so-called semi-synthetic cannabinoids, and they structurally closely resemble the main psychoactive component of cannabis, Δ9-tetrahydrocannabinol. Knowledge of new (semi-)synthetic cannabinoids is essential to help identify them in authentic forensic case samples. Therefore, the aim of the study was to examine two commercially available electronic cigarette liquid products claiming to contain cannabinoids and characterize the structures of the main compounds. The liquid products were analyzed by gas chromatography-mass spectrometry (GC-MS), GC-quadrupole time-of-flight mass spectrometry (GC-QTOF-MS), and liquid chromatography-high-resolution mass spectrometry (LC-HRMS). In product A, typical cannabinoids (cannabidiol, cannabigerol, and cannabinol) and terpenes (α-caryophyllene and ß-caryophyllene) were identified by comparison with reference materials. An unknown peak was isolated by semi-preparative high-performance LC, analyzed by nuclear magnetic resonance (NMR) spectroscopy, and identified to be Δ9-tetrahydrocannabihexol acetate (Δ9-THCH-O). To the authors' knowledge, this is the first report of the identification of Δ9-THCH-O in commercially available products. Another compound estimated as cannabihexol acetate was also detected. In product B, cannabidiol, cannabinol, α-caryophyllene, and ß-caryophyllene were identified, while two unknown peaks were estimated as tetrahydrocannabidiol isomers. Despite products A and B being labeled to contain "60% HHCPM" and "80% 10-OH-HHC," respectively, no such compounds were detected. The findings of this study could help detect Δ9-THCH-O in case samples and highlight the need to keep monitoring commercial products to identify new drugs, while warning that the package labels cannot be trusted.

Assessing residual fragrances on skin after body washing: Optimization of an analytical method using solid-phase microextraction coupled with gas chromatography-mass spectrometry.

OBJECTIVE: The aim of this study is to develop and optimize a method for evaluating the persistence of residual fragrance after body washing, addressing a significant requirement in the development of personal care products. The main objective is to establish a reliable, sensitive and reproducible analytical technique to assess fragrance longevity on skin post-use of body wash products. METHODS: Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) is used to analyse residual fragrances. We investigate the extraction efficiencies of various SPME fibres and compare different methods for sampling skin-emitted fragrances, including tape stripping and sealed glass funnels. A controlled body-washing procedure is implemented to standardize the cleansing process. RESULTS: Our findings indicate that the relative standard deviation for measuring five distinct fragrances is within the range of 3%-14%, highlighting the precision of the method. A notable variance exists in the extraction efficiency of fragrances using different types of SPME fibres, with some exhibiting over a threefold difference. Furthermore, the glass funnel method for fragrance collection demonstrates an 11.7 times greater sensitivity to galaxolide than that of the tape-stripping method. Residual fragrances with base notes as the main components can be detected on the skin up to 24 h after body washing. CONCLUSION: The optimized method for residual fragrance evaluation developed in this study offers a robust tool for analysing fragrance components persisting on the skin for up to 24 h post-wash. This advancement facilitates a deeper understanding of fragrance longevity in personal care products, enabling comparative analyses between different products.

OBJECTIF: l'objectif de cette étude est de développer et d'optimiser une méthode d'évaluation de la persistance du parfum résiduel après la toilette du corps, répondant à une exigence significative dans le développement de produits de soins personnels. L'objectif principal est d'établir une technique analytique fiable, sensible et reproductible pour évaluer la longévité des parfums sur la peau après utilisation de produits de toilette pour le corps. METHODES: la microextraction en phase solide de l'espace de tête (HS­SPME) couplée à la chromatographie en phase gazeuse­spectrométrie de masse (GC­MS) est utilisée pour analyser les parfums résiduels. Nous étudions l'efficacité de l'extraction de diverses fibres SPME et nous comparons différentes méthodes d'échantillonnage des senteurs émises par la peau, y compris le stripping sur ruban adhésif et les entonnoirs en verre scellés. Une procédure contrôlée de lavage du corps est mise en place pour standardiser le processus de nettoyage. RÉSULTATS: nos résultats indiquent que l'écart­type relatif pour mesurer cinq parfums distincts se situe dans la plage de 3% à 14%, ce qui souligne la précision de la méthode. Une variance notable existe dans l'efficacité d'extraction des parfums utilisant différents types de fibres de SPME, certaines présentant plus d'un triplement de différence. En outre, la méthode de l'entonnoir en verre pour la collecte des parfums démontre une sensibilité au galaxolide 11,7 fois supérieure à celle de la méthode de stripping sur ruban adhésif. Les parfums résiduels avec des notes de fond comme principaux composants peuvent être détectés sur la peau jusqu'à 24 h après le lavage du corps. CONCLUSION: la méthode optimisée pour l'évaluation du parfum résiduel développée dans cette étude offre un outil fiable pour analyser les composants du parfum persistant sur la peau jusqu'à 24 heures après le lavage. Cette avancée offre une meilleure compréhension de la longévité des parfums dans les produits de soins personnels, permettant des analyses comparatives entre les différents produits.

Analysis of chlordecone and its transformation products in environmental waters by a new SPME-GC-MS method and comparison with LLE-GC-MS/MS and LLE-LC-MS/MS: A case study in the French West Indies.

Among the numerous organochlorines (OCs) applied in the French West Indies (FWI), chlordecone (hydrated form C10Cl10O2H2; CLD) still causes major environmental pollution nowadays. A recent report revealed the unexpected presence in FWI environment of transformation products (TPs) of CLD not routinely monitored due to a lack of commercial standards. Here, we present a method for surface waters and groundwaters to analyze CLD, its main TPs (hydroCLDs, chlordecol (CLDOH), 10-monohydroCLDOH and polychloroindenes) and other OCs. We developed an SPME-GC-SIM/MS method with a PDMS-DVB fiber. Since CLDOH-d commonly used as internal standard (IS) proved unsuitable, we synthesized several IS candidates, and finally identified 10-monohydro-5-methyl-chlordecol as a satisfactory IS for CLDOH and 10-monohydroCLDOH avoiding the use of 13C-labelled analogue. LODs for CLD and its TPs varied from 0.3 to 10 ng/L, equal to or below LODs of the two laboratories, BRGM (the French geological survey) and LDA26 (one of the French Departmental Analytical Laboratories), requested in FWI pollution monitoring that used liquid-liquid extractions and advanced facilities (LLE-GC-MS/MS and LLE-LC-MS/MS methods, respectively). Then, we extended the multi-residue method to 30 OCs (CLD and its TPs, mirex, ß-HCH, lindane, dieldrin, aldrin, HCB, hexachlorobutadiene, TCE, PCE) and applied it to 30 surface and ground waters from FWI. While CLD, 8- and 10-monohydroCLD, CLDOH, 10-monohydroCLDOH, dieldrin, and ß-HCH were detected and quantified, pentachloroindene, another CLD TP, was sporadically found in trace levels. A comparison with BRGM and LDA26 confirmed the interest of the SPME method. Results suggested an underestimation of CLDOH and an overestimation of high CLD concentrations with one of the currently used routine protocol. In light of these findings, previous temporal monitoring of environmental waters in FWI were re-examined and revealed some atypical values, which may indeed be due to analytical bias. These discrepancies call for intensified efforts to reliably quantify CLD and its TPs.

Stable isotope dilution assay and HS-SPME-GCMS quantification of key aroma volatiles of Australian pineapple (Ananas comosus) cultivars.

Pineapple aroma is one of the most important sensory quality traits that influences consumer purchasing patterns. Reported in this paper is a high throughput method to quantify in a single analysis the key volatile organic compounds that contribute to the aroma of pineapple cultivars grown in Australia. The method constituted stable isotope dilution analysis in conjunction with headspace solid-phase microextraction coupled with gas-chromatography mass spectrometry. Deuterium labelled analogues of the target analytes purchased commercially were used as internal standards. Twenty-six volatile organic compounds were targeted for quantification and the resulting calibration functions of the matrix -matched validated method had determination coefficients (R2) ranging from 0.9772 to 0.9999. The method was applied to identify the key aroma volatile compounds produced by popular pineapple cultivars such as 'Aus Carnival', 'Aus Festival', 'Aus Jubilee', 'Aus Smooth (Smooth Cayenne)' and 'Aussie Gold (73-50)', grown in Queensland, Australia. Pineapple cultivars varied in its content and composition of free volatile components, which were predominantly comprised of esters, followed by terpenes, alcohols, aldehydes, and ketones.