High-sensitivity nanoflow liquid chromatography (nLC) is seldom employed in untargeted metabolomics because current sample preparation techniques are inefficient at preventing nanocapillary column performance degradation. Here, we describe an nLC-based tandem mass spectrometry workflow that enables seamless joint analysis and integration of metabolomics (including lipidomics) and proteomics from the same samples without instrument duplication. This workflow is based on a robust solid-phase micro-extraction step for routine sample cleanup and bioactive molecule enrichment. Our method, termed proteomic and nanoflow metabolomic analysis (PANAMA), improves compound resolution and detection sensitivity without compromising the depth of coverage as compared with existing widely used analytical procedures. Notably, PANAMA can be applied to a broad array of specimens, including biofluids, cell lines, and tissue samples. It generates high-quality, information-rich metabolite-protein datasets while bypassing the need for specialized instrumentation.

The chemical industry explosion in the 20th century has led to increased environmental pollution, affecting fauna, flora, and waterways. These substances alter water\'s taste, color, and smell, making it unfit for consumption or toxic. Agricultural water networks face threats from pollution before and after treatment. Some chemical contaminants, like pesticides, are embedded in natural biogeochemical cycles. In this study, we developed a simple and low-cost procedure for the fabrication of needles coated with polydimethylsiloxane (PDMS) as an efficient sorbent for the microextraction of organic pollutant traces from water. The prepared needles were used as an alternative for commercial solid-phase micro-extraction (SPME) devices in analytical chemistry. The PDMS polymeric phase was characterized by Fourier-transform infrared spectroscopy (FT-IR), thermogravimetry (TGA), and scanning electron microscopy (SEM). The PDMS-coated needles were used for extraction of thirteen pesticides by direct-immersion solid-phase microextraction (DI-SPME) from contaminated waters, followed by determination with gas chromatography-mass spectrometry (GC-MS). The developed analytical method showed limits of detection (LODs) between 0.3 and 2.5 ng mL-1 and RSDs in the range of 0.8-12.2%. The homemade needles were applied for the extraction of pesticides in surface and ground aqueous samples collected from an agricultural area. Several target pesticides were identified and quantified in the investigated water samples.

Headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME-GC-MS) offers an alternative analysis method for isoeugenol (an active ingredient in fish sedatives) that avoids the use of organic solvents, simplifies sample preparation, and can be fully automated. This work focuses on developing and evaluating an HS-SPME-GC-MS method for isoeugenol in aquaculture samples and testing the stability of isoeugenol itself. Because of isoeugenol\'s relatively low volatility, more polar SPME fiber coatings (polyacrylate and polydimethylsiloxane/divinylbenzene) had better performance and the headspace extractions took over 30 min to reach equilibrium. Additionally, it was found that isoeugenol was relatively unstable compared to a deuterated standard (d3-eugenol) in the presence of water. To address this, after the fish samples were homogenized with water, they were heated at 50 °C for 1 h prior to analysis for equilibration. By using the method developed in this work, isoeugenol\'s detection limits in multiple aquaculture matrices (shrimp, tilapia, and salmon) were in the low ng/g range (<15 ng/g), well below the target testing level (200 ng/g). Additionally, by adding d3-eugenol as an internal standard, excellent linearity (R2 > 0.98), accuracy (97-99% recoveries), and precision (5-13% RSDs) were all achieved.

BACKGROUND: The selection of the sample treatment strategy is a crucial step in the metabolomics workflow. Solid phase microextraction (SPME) is a sample processing methodology with great potential for use in untargeted metabolomics of tissue samples. However, its utilization is not as widespread as other standard protocols involving steps of tissue collection, metabolism quenching, homogenization, and extraction of metabolites by solvents. Since SPME allows us to perform all these steps in one action in tissue samples, in addition to other advantages, it is necessary to know whether this methodology produces similar or comparable metabolome and lipidome coverage and performance to classical methods.
RESULTS: SPME and homogenization with solid-liquid extraction (Homo-SLE) sample treatment methods were applied to healthy murine kidney tissue, followed by comprehensive metabolomics and lipidomics analyses. In addition, it has been tested whether freezing and storage of the tissue causes alterations in the renal metabolome and lipidome, so the analyses were performed on fresh and frozen tissue samples Lipidomics analysis revealed the exclusive presence of different structural membrane and intracellular lipids in the Homo-SLE group. Conversely, all annotated metabolites were detected in both groups. Notably, the freezing of the sample mainly causes a decrease in the levels of most lipid species and an increase in metabolites such as amino acids, purines, and pyrimidines. These alterations are principally detected in a statistically significant way by SPME methodology. Finally, the samples of both methodologies show a positive correlation in all the analyses.
CONCLUSIONS: These results demonstrate that in SPME processing, as long as the fundamentals of non-exhaustive extraction in a pre-equilibrium kinetic regime, extraction in a tissue localized area, the chemistry of the fiber coating and non-homogenization of the tissue are taken into account, is an excellent method to use in kidney tissue metabolomics; since this methodology presents an easy-to-use, efficient, and less invasive approach that simplifies the different sample processing steps.

UNASSIGNED: Normothermic ex vivo kidney perfusion (NEVKP) is designed to replicate physiological conditions to improve graft outcomes. A comparison of the impact of hypothermic and normothermic preservation techniques on graft quality was performed by lipidomic profiling using solid-phase microextraction (SPME) chemical biopsy as a minimally invasive sampling approach.
UNASSIGNED: Direct kidney sampling was conducted using SPME probes coated with a mixed-mode extraction phase in a porcine autotransplantation model of the renal donor after cardiac death, comparing three preservation methods: static cold storage (SCS), NEVKP, and hypothermic machine perfusion (HMP). The lipidomic analysis was done using ultra-high-performance liquid chromatography coupled with a Q-Exactive Focus Orbitrap mass spectrometer.
UNASSIGNED: Chemometric analysis showed that the NEVLP group was separated from SCS and HMP groups. Further in-depth analyses indicated significantly (p < 0.05, VIP > 1) higher levels of acylcarnitines, phosphocholines, ether-linked and longer-chain phosphoethanolamines, triacylglycerols and most lysophosphocholines and lysophosphoethanolamines in the hypothermic preservation group. The results showed that the preservation temperature has a more significant impact on the lipidomic profile of the kidney than the preservation method\'s mechanical characteristics.
UNASSIGNED: Higher levels of lipids detected in the hypothermic preservation group may be related to ischemia-reperfusion injury, mitochondrial dysfunction, pro-inflammatory effect, and oxidative stress. Obtained results suggest the NEVKP method\'s beneficial effect on graft function and confirm that SPME chemical biopsy enables low-invasive and repeated sampling of the same tissue, allowing tracking alterations in the graft throughout the entire transplantation procedure.

The major and possibly only component of the sex attractant pheromone of the moth Hemileuca nevadensis (Lepidoptera: Saturniidae) from southern California was determined to be (E10,Z12)-hexadecadienal (E10,Z12-16:Ald). Detectable quantities of the analogs (E10,Z12)-hexadecadien-1-yl acetate (E10,Z12-16:Ac) and (E10,Z12)-hexadecadien-1-ol (E10,Z12-16:OH) were also present in solvent extracts of sex pheromone glands, and stimulated male antennae in coupled gas chromatography-electroantennogram detector (GC-EAD) assays. GC-EAD traces from solid phase microextraction (SPME) wipe samples of sex pheromone glands of calling females confirmed the presence of E10,Z12-16:Ald and traces of E10,Z12-16:OH on the gland surface, but E10,Z12-16:Ac was not detected. Despite evidence for the presence of all three compounds in extracts, behavioral responses to synthetic compounds in the field suggested that only E10,Z12-16:Ald is required for optimal attraction.

The increasing interest in hemp and cannabis poses new questions about the influence of drying and storage conditions on the overall aroma and cannabinoids profile of these products. Cannabis inflorescences are subjected to drying shortly after harvest and then to storage in different containers. These steps may cause a process of rapid deterioration with consequent changes in precious secondary metabolite content, negatively impacting on the product quality and potency. In this context, in this work, the investigation of the effects of freeze vs tray drying and three storage conditions on the preservation of cannabis compounds has been performed. A multi-trait approach, combining both solid-phase microextraction (SPME) two-dimensional gas chromatography coupled to mass spectrometry (SPME-GC × GC-MS) and high-performance liquid chromatography (HPLC), is presented for the first time. This approach has permitted to obtain the detailed characterisation of the whole cannabis matrix in terms of volatile compounds and cannabinoids. Moreover, multivariate statistical analyses were performed on the obtained data, helping to show that freeze drying conditions is useful to preserve cannabinoid content, preventing decarboxylation of acid cannabinoids, but leads to a loss of volatile compounds which are responsible for the cannabis aroma. Furthermore, among storage conditions, storage in glass bottle seems more beneficial for the retention of the initial VOC profile compared to open to air dry tray and closed high-density polyethylene box. However, the glass bottle storage condition causes formation of neutral cannabinoids at the expenses of the highly priced acid forms. This work will contribute to help define optimal storage conditions useful to produce highly valuable and high-quality products.

A robust biocompatible solid-phase microextraction (SPME) fiber, so-called Ti/APTS/GA/CS, was prepared by chemical bonding of cross-linked glutaraldehyde-chitosan to the surface of a titanium wire using APTS. The fiber was applied for sampling of phytohormones in plant tissues, followed by HPLC-UV analysis. The structure and morphology of the fiber coating was investigated by FT-IR, SEM, EDX, XRD, and TGA techniques. A Box-Behnken design was implemented to optimize the experimental variables. The calibration graphs were linear over a wide linear range (0.5-200 μg L-1) with LODs over the range of 0.01-0.06 μg L-1. The intra-day and inter-day precisions were found to be 1.3-6.3% and 4.3-7.3%, respectively. The matrix effect values ranged from 86.5% to 111.7%, indicating that the complex sample matrices had an insignificant effect on the determination of phytohormones. The fiber was successfully employed for the direct-immersion SPME (DI-SPME-HPLC) analysis of the phytohormones in cucumber, tomato, date palm, and calendula samples.

Raisins, derived from dried grapes, represent a valuable commodity rich in secondary metabolites, particularly volatile organic compounds (VOCs). The primary objective of this review is to identify the VOCs that are influencing the aromatic profile of raisins to improve consumer preferences. However, extensive research has been done to optimize grape drying methods for different raisin attributes. In the context of this review, an in-depth investigation of published literature revealed the extraction of over 120 VOCs from raisins using SPME. Furthermore, we explored factors shaping raisin aroma and the sources of VOC generation. This review aims to pinpoint research gaps and provide an opportunity for future developments in studying raisins\' aroma. This involves integrating advanced analytical techniques, examining processing method impacts, and considering consumer perception to enhance the overall understanding of raisin aromas. The outcomes are anticipated to provide valuable insights for the industry and the scientific community.

Bee bread is one of the least studied bee products. In this study, ten bee bread samples were characterized using palynology and HS-SPME-GC-MS (headspace solid-phase microextraction gas chromatography-mass spectrometry). In total, over one hundred different volatile components were identified, belonging to different chemical groups. Only ten common components were detected in all the samples. These volatiles were ethanol, ethylene chloride, ethyl acetate, acetic acid, α-pinene, furfural, nonane, nonanal, n-hexane and isovaleric acid. Several other components were commonly shared among various bee bread samples. Over sixty detected compounds have not been previously reported in bee bread. The analysis required a mild extraction temperature of 40 °C, as higher temperatures resulted in the Maillard reaction, leading to the production of furfural. The profile of volatile compounds of the tested bee pollen samples was complex and varied. Some relationships have been shown between botanical origin and volatile organic compound profile.