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Microplastics (MPs) in the air are one of the major concerns due to their possible health risks. In addition, airborne microplastics act as a carrier for several toxic air pollutants and cause carcinogenic, mutagenic and teratogenic effects. Nylon 66 is one of the most abundant MPs in the microenvironments. In this study, we report an optimized method for the quantification of nylon 66 MPs present in the fine particulate matter (PM2.5) using high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). The optimized method exhibited excellent linearity, recovery rates, intraday and interday precision and sensitivity. The optimized method was deployed to carry out a pilot study to measure the mass concentrations of nylon 66 microplastics present in the inhalable fraction of particulate matter collected in a shopping complex. The observed mass concentrations of nylon 66 MPs in this study are in the range from 0.30 ng m−3 to 4.37 ng m−3. This study demonstrates the presence of inhalable fraction of nylon 66 MPs in the indoor environment and their mass concentrations were determined using HPLC-MS/MS. [ABSTRACT FROM AUTHOR]

AbstractA method for the determination of eight benzenes (BTEXs) and twelve chlorobenzenes (CBs) in goat’s milk by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS/MS) was developed. The study investigated the impact of various factors such as extraction fiber type, salt amount, equilibrium conditions, and desorption conditions on the outcomes. Target analytes were separated on a DB-HeavyWAX column and quantified using the external standard method. The results showed that the target compounds had a good linear relationship in the range of 0.01 ∼ 50 μg/L (R2 > 0.997), the limit of detection (LOD) was 0.003 ∼ 0.150 μg/L, and the limit of quantification (LOQ) was 0.01 ∼ 0.50 μg/L. The average recoveries were 82%–116% and the relative standard deviation (RSD) was 0.8%–17.3% under the three addition levels of 1×, 2×, and 10 × LOQ. In a survey of twenty goat’s milk samples, only ethylbenzene, xylenes, cumene, chlorobenzene, and 1,4-dichlorobenzene were detected at levels exceeding their respective limits of quantification. The method was evaluated using two ecological scales (Eco-Scale), GAPI and AGREEN, to verify its environmental friendliness and applicability. This method is simple, green, and efficient, which provides a certain theoretical basis for the production and quality safety evaluation of dairy products. [ABSTRACT FROM AUTHOR]

Objective: NeoBase 2 Non-derivatized MSMS assay kit (NeoBase 2 kit) was used for newborn screening, the performance of the NeoBase 2 kit should be validated before its implementation in clinical diagnostic laboratories. Methods: Leftover dried blood spot samples, quality control materials in the NeoBase 2 kit, and proficiency testing materials received from the NSQAP were used. Precision, accuracy, LOD, LLOQ, recovery, and stability were carried out to verify the performance of the Waters ACQUITY TQD MS/MS system with the NeoBase 2 kit for newborn screening. Cutoffs were determined and analytes requiring different cutoffs in preterm neonates were investigated. Results: Within-run and between-run precisions ranged from 3.95% to 14.41%. The accuracy and stability were within 15%. All analytes demonstrated acceptable LOD, LLOQ, and recoveries. Cutoffs for term and preterm neonates were established. Conclusions: The performance of the NeoBase 2 kit is acceptable and can be implemented in clinical diagnostic laboratories. [ABSTRACT FROM AUTHOR]

Anthocyanins (ANCs), a kind of natural pigments, are widely present in food substrates. Evidence has shown that ANCs can promote health in terms of anti-oxidation, anti-tumor, and anti-inflammation. However, the oxidative stability of ANCs limits accurate quantitation and analysis. Therefore, faster, more accurate, and highly sensitive extraction and determination methods are necessary for understanding the role of ANCs in medicine and food. This review presents an updated overview of pretreatment and detection techniques for ANCs in various food substrates since 2015. Liquid-liquid extraction and various green solvent extraction methods, such as accelerated solvents extraction, deep eutectic solvents extraction, ionic liquids extraction, and supercritical fluid extraction, are commonly used pretreatment methods for extraction and purification of ANCs. Liquid chromatography coupled with different detectors (tandem mass spectrometry and UV detectors) and spectrophotometry methods are some of the determination methods for ANC. This study has updated, compared, and discussed different pretreatment and analysis methods. Moreover, the advanced methods and development prospects in this field are comprehensively summarized, which can provide references for further utilization of ANCs. [ABSTRACT FROM AUTHOR]

We established an efficient analytical approach for simultaneous determination of benthiavalicarb-isopropyl and its four metabolites (KIF-230-M1, KIF-230-M3, KIF-230-M4, and KIF-230-M5) in fruits and vegetables. Samples were extracted with acidified acetonitrile, with octadecylsilane and graphitised carbon black as sorbent for clean-up, and UHPLC-MS/MS for determination. The approach was determined at spikes of 5, 50, and 500 μg kg−1. The recoveries of the six matrices analyzed ranged from 74.5% to 115.6% with 0.5–12.6% for intra-day RSDr (n = 5), and 0.4–13.8% for inter-day RSDR (n = 15). The five analytes in all matrices achieved high linearity (R2 > 0.9917). The limit of quantification (LOQ) of benthiavalicarb-isopropyl as well as its four metabolites in all matrices was 5 μg kg−1. This analytical approach allows for monitoring residues of benthiavalicarb-isopropyl and its metabolites in vegetables and fruits. [ABSTRACT FROM AUTHOR]

This study established a simple, rapid, and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for the simultaneous quantification of contezolid and its major metabolite M2 in human plasma and cerebrospinal fluid (CSF). We used isotope-labeled internal standards (IS) along with protein precipitation to efficiently eliminate impurities. The ion transition was m/z 409.1 → 269.1 for contezolid, m/z 414.1 → 269.0 for contezolid-d5, m/z 445.1 → 385.1 for M2, and m/z 450.2 → 390.1 for M2-d5. The flow rate was 0.4 mL/min with a run time of 2.5 min. Validation results demonstrated that the calibration range was 10–5000 ng/mL for contezolid, and 5–2500 ng/mL for M2 in plasma and CSF. Both analytes exhibit excellent linear relationships (all R2 ≥ 0.99). Intra- and inter-batch accuracy and precision for all quality control (QC) levels were within ± 15%, including the lower limit of quantification (LLOQ). The recoveries of contezolid and M2 were 92.60–100.4% and 92.26–99.61% in plasma and 93.33–99.19% and 91.31–98.21% in CSF, respectively. The matrix effects for contezolid and M2 were 97.20–110.3% and 98.27–105.47% in plasma and 105.25–112.99% and 103.35–109.84% in CSF, respectively. The coefficients of variation (CV%) were ≤ 12.58%. Conteozolid and M2 remained stable in plasma and CSF. This study has established a simple and accurate method for determining contezolid and M2 in human plasma and CSF, making it a valuable tool for monitoring the efficacy of central nervous system (CNS) drugs. [ABSTRACT FROM AUTHOR]

Coumarin and furocoumarins characterization in cosmetics plays an important role in protecting consumer health. The analytical technique mostly employed for the analysis of these molecules is certainly liquid chromatography coupled to photodiode array or mass spectrometer detectors. The aim of this article was to investigate on the oxygen heterocyclic compounds content in fifty hydro alcoholic fragrances using a fast, sensitive and eco-friendly liquid chromatography coupled to a triple quadrupole mass spectrometer detector analytical method without any sample pre-treatment. To the best of the author’s knowledge, this is the first research article on the quantification of thirty-six oxygen heterocyclic compounds in hydro alcoholic fragrances in less than 4 min and with the use of water/ethanol as mobile phase. Thanks to the good performance of the analytical method used, this can be proposed among the routine methods for the quality control of cosmetics and finished products. [ABSTRACT FROM AUTHOR]

A method for determining human epidermal growth factor (hEGF) in cosmetics was developed using solid-phase extraction with high-performance liquid chromatography – tandem mass spectrometry. The sample was extracted and purified by a mixed anionic solid-phase extraction column (MAX), and the eluent was passed through a nylon filter membrane into a polypropylene vial. The matrix-matched external standard method was used to quantify the analyte in multi-reaction monitoring mode. The analyte had an excellent peak shape within 11 min with a linear range from 5 to 80 ng/mL and a linear correlation coefficient (r) of 0.9995. The limit of detection and limit of quantification were 0.75 and 2.5 μg/kg, respectively. The recovery of the target was from 81.5% to 88.8%, and the relative standard deviation was between 1.16% and 5.07%. The results met the International Organization for Standardization 12787 standard. The established method was successfully applied to 30 cosmetic samples. The proposed method is sensitive, accurate, reliable, and suitable for the quantitative confirmation of hEGF and monitoring its illegal addition to cosmetics. [ABSTRACT FROM AUTHOR]

Polygonum Amplexicaule Radix is a traditional Chinese medicine for promoting blood circulation and removing blood stasis, which is often used to treat thrombotic diseases. However, its potential anticoagulant active ingredients have been unexplored. In this study, a method for rapid screening of anticoagulant active ingredients from P. amplexicaule by affinity-ultrafiltration (AUF) and high-performance – tandem mass spectrometry (HPLC-MS/MS) was established, which using thrombin as an affinity receptor target. 5 potential anti-thrombin active components were screened: gallic acid, procyanidin B2-3''O-gallate, 11-O-galloylbergenin, (-)-epicatechin gallate and di-galloyl-O-bergenin by AUF and HPLC-MS/MS. The inhibitory ability of these active ingredients to thrombin was confirmed by in vitro activity experiments and molecular docking, hence justifying that P. amplexicaule is a traditional Chinese medicine with excellent anticoagulation effects. Meanwhile, it has been shown that AUF-MS could be a way rapid screening for active substances. [ABSTRACT FROM AUTHOR]

A simple method for the determination of 19 types of phthalate acid ester plasticizers in raw textile solid waste has been developed by employing ultrasonic extraction coupled with gas chromatography – tandem mass spectrometry (GC-MS/MS). The evaluation of the plasticizers in several textile solid wastes showed that the levels were high, especially dimethylglycol phthalate. The extraction solvent, ultrasonic time, and ultrasonic temperature were optimized. Hexane was adopted as the extraction solvent, and ultrasonic extraction was performed at 20 °C for 30 min. A linear relationship from 0.02 to 1000 ng/mL was obtained with correlation coefficients(r) greater than 0.996. The limits of quantitation were from 0.08 to 30.70 µg/L based upon a signal-to-noise ratio (S/N) of 10. The recoveries were from 90.1% to 108.9% and the relative standard deviation between 0.78% and 9.43%. The method can be used for rapid screening and quantitative analysis of textile solid waste due to the simple, sensitive, and accurate assay. [ABSTRACT FROM AUTHOR]

Accurate measurement of endogenous steroid hormones in serum is a powerful tool for understanding the status of human adrenal diseases. Isotope dilution–liquid chromatography–tandem mass spectrometry is the most commonly used method for determination of steroids in serum. In this study, we used a laboratory-constructed quadrupole-linear ion trap (Q-LIT) tandem mass spectrometer to develop a new method for the quantification of five steroid hormones in serum. A simple and efficient pretreatment was improved, wherein the serum was extracted once by a mixed solvent of 1.0 mL of ethyl acetate and n-hexane. Using the optimized method, the regression coefficients of the calibration curves were all higher than 0.99, the limits of detection were from 0.31 to 1.25 ng mL−1, and the limits of quantification were between 1.00 and 2.50 ng mL−1. The intra-day (n = 3) relative standard deviations ranged from 4.24% to 13.79%, and the inter-day (n = 3) relative standard deviations from 3.99% to 11.43%. After internal standard correction, the relative recoveries of all steroids were from 86.08% to 106.60%. Twenty-two serum samples were analyzed by Q-LIT, which was compared with commercial triple quadrupole mass spectrometer. The results of the instruments had high consistency. Therefore, Q-LIT accurately quantified steroid hormones in human samples and may be used for clinical diagnosis and monitoring of hormone-dependent diseases. [ABSTRACT FROM AUTHOR]

Herbicide residue levels were analyzed in agricultural soils of Batak plain and health risk assessments were made for relevant pesticides. Herbicide contamination levels were analyzed with the use of Quick-Easy-Cheap-Efficient-Rugged-Safe (QuEChERS)-liquid chromatography/tandem mass spectrometry (LC–MS/MS) procedure. Herbicide-free soil samples were spiked at two different levels. Overall recovery of the method was 87.32%. Present findings were parallel to SANTE recovery limits. About 50% of collected samples from the study sites contained herbicides at different concentrations. Totally, eight herbicides were detected, and herbicide concentrations ranged between 1.085 and 1724.23 μg kg−1. Metolachlor had the highest concentration (1724.23 μg kg−1) in a sample taken close to the pesticide waste disposal area. Six herbicides were detected at different concentrations in the same sample. Persistent herbicides (terbuthylazine and pendimethalin) were detected in 35 samples. Risk assessments revealed that hazard index (HI) and hazard quotient (HQ) were less than 1. The greatest HQ values were identified for terbuthylazine as 2772.48 × 10−7 and 20793.61 × 10−7 for adults and children, respectively. The HI for all herbicides were 3916.05 × 10−7 for adult and 29370.39 × 10−7 for children. [ABSTRACT FROM AUTHOR]

Proteomics has been used extensively in the field of mycology, mainly in trying to understand the complex network of protein-protein interactions that has been implicated in the molecular functions of fungi. It is also a useful tool to compare metabolic differences within a genus. Species of Pseudogymnoascus, a genus under the phyla Ascomycota, have been shown to play an important role in the soil environment. They have been found in both polar and temperate regions and are a known producer of many extracellular hydrolases that contribute to soil decomposition. Despite the apparent importance of Pseudogymnoascus spp. in the soil ecosystem, investigations into their molecular functions are still very limited. In the present study, proteomic characterization of six Pseudogymnoascus spp. isolated from three biogeographic regions (the Arctic, Antarctic, and temperate regions) was carried out using tandem mass spectrometry. Prior to proteomic analysis, the optimization for protein extraction was carried out. Trichloroacetic acid‑acetone‑phenol was found to be the best extraction method to be used for proteomic profiling of Pseudogymnoascus spp. The proteomic analysis identified 2003 proteins that were successfully mapped to the UniProtKB database. The identified proteins were clustered according to their biological processes and molecular functions. The shared proteins found in all Pseudogymnoascus spp. (1201 proteins) showed a significantly close relationship in their basic cellular functions, despite differences in morphological structures. Analysis of Pseudogymnoascus spp. proteome also identified proteins that were unique to each region. However, a high number of these proteins belonged to protein families of similar molecular functions, namely, transferases and hydrolases. Our proteomic data can be used as a reference for Pseudogymnoascus spp. across different global regions and a foundation for future soil ecosystem function research. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) analysis has become crucial due to their presence in the environment, their persistence and potential health risks. These compounds are commonly used in food contact materials (FCM) as a coating to provide water and grease-repellent properties. One of the pathways for PFAS to enter the human body is either through direct consumption of contaminated food or indirectly through migration from FCM into food. The purpose of this study was to investigate where the initial contamination of paper FCM occurs. We analysed paper material consisting of fresh fibre and secondary materials, intended to produce food packaging for the presence of PFAS. The samples were extracted and analysed for 23 different PFAS substances using the targeted approach with LC tandem mass spectrometry (LC-MS/MS). This analytical technique detects specific, easily ionisable PFAS with high sensitivity. However, one drawback of this approach is that it allows the identification of less than 1% of the PFAS known today. For this reason, we used combustion ion chromatography (CIC) to determine the content of extractable organic fluorine compounds (EOF) and compare it to the total fluorine content. The targeted analysis using LC-MS/MS measured an average sum concentration of PFAS of 0.17 ng g−1 sample. Our research shows that the primary PFAS contamination happens during the recycling process since all of the samples in which the targeted PFAS were measured belonged to the secondary material. The most frequently detected analytes were PFOA and PFOS, detected in 90% and 62% of the samples, respectively, followed by PFBS (in 29% of the samples). CIC showed that measured PFAS via LC-MS/MS amount to an average of 2.7 × 10−4% of total fluorine content, whereas the EOF was under the LOD in all of the measured samples. This result highlights the complexity of the accurate determination of PFAS compounds, displaying what kind of information the chosen methods provide. [ABSTRACT FROM AUTHOR]

To investigate cannabinoid content and profiles, 16 cannabinoids were quantified in 30 commercial hemp seed edible oils. In addition, one hemp seed oil was subjected to thermal processing up to 200 °C for up to 60 min. UHPLC-MS/MS was used for analysis. The content of cannabinoids in the samples ranged from 9 to 279 mg kg−1 (sum) and for Δ9-tetrahydrocannabinol (Δ9-THC) from 0.2 to 6.7 mg kg−1. Three samples exceeded the EU Δ9-THC equivalent maximum levels of 7.5 mg kg−1 for hemp seed oils. Cannabinoid profiles can provide indications of different product characteristics (e.g. degree of processing, variety of plant material). Furthermore, intense thermal processing (200 °C, 60 min) led to 38% decrease in sum cannabinoid content (sum of all analysed cannabinoids in this study), 99% decrease in cannabinoid acids, and 22% increase in Δ9-THC. [ABSTRACT FROM AUTHOR]

A novel post-synthetic modification of magnetite@MIL-53(Fe)-NH2 core-shell nanocomposite was performed to extract ultra-trace amounts of Pd(II) ions from the real samples. To explore and optimise the effect of parameters on the preconcentration design of the experiment was employed. The highest removal efficiency in the adsorption step was obtained using the following condition: pH of sample, 6.5; adsorption time, 3.8 min; magnetite@MIL-53(Fe)-NH-PITC NPs amount, 20 mg. The highest extraction recovery (%) was achieved using 0.8 mL of 0.85 mol L−1 HCl as the desorbing solution; and by applying an elution time of 3.5 min. Afterwards, to study the equilibrium data, various adsorption isotherm models were explored. The data showed that the Langmuir model describes the adsorption process better than the other models. Eventually, the maximum adsorption capacity and model constant equal to 100 mg g−1 and 0.11 L mg−1, were obtained, respectively. Besides, the kinetic data were well fitted to the pseudo-second-order based on the highest correlation coefficient that was achieved. The limit of detection, the limit of quantification, and the linear range of the proposed method were 0.05 μg L−1, 0.2 μg L−1, and 0.2–100 μg L−1 (r2 = 0.9936), respectively. The precision was explored as relative standard deviation value at three concentration of 0.5, 10, 75 ng mL−1 (n = 3) that was 12.5%, 9.3% and 6.6%, respectively. Ultimately, the new magnetic adsorbent could be employed for extraction/quantification of ultra-trace amounts of Pd(II) ions in real samples and the relative recovery values were obtained in the range of 88–102%. [ABSTRACT FROM AUTHOR]

A simple, rapid and sensitive method for the determination of aflatoxins in peanut oil was developed using MIL-101(Cr) material filled syringe filter for one-step solid-phase extraction (SPE) with high-performance liquid chromatography—tandem mass spectrometry (HPLC-MS/MS) detection. The MIL-101(Cr) sorbent was characterized and its mass, the loading solution, and the eluent were optimized; under these conditions, a matrix matching internal standard method was developed. The linear range was from 0.1 to 20 ng/mL with correlation coefficient (r) exceeding 0.9998. The recoveries were between 94.7% and 105.9% with relative standard deviations from 2.02% 6.88%. The recoveries of inter-day and intra-day measurements were from 93.0% to 98.5% and 97.6% to 100.7%. The precision values for inter-day and intra-day analyses were from 6.09% to 7.68% and 2.56% to 4.30%, respectively. The pretreatment efficiency of the developed method was superior to literature procedures and used to determine aflatoxins in 126 peanut oil samples from local markets. 38 samples had positive results and 1 sample exceeded the allowable limit. Hence, the developed protocol was suitable for the determination of aflatoxins in peanut oil. [ABSTRACT FROM AUTHOR]

This document titled "(Self) Assembled news: recent highlights from the supramolecular chemistry literature (quarter 3, 2024)" provides a summary of recent advancements in the field of supramolecular chemistry. The first highlight discusses the development of a supramolecular system that functions as a molecular ion pump, converting light energy into work and pumping KCl across a hydrophobic barrier against the concentration gradient. The second highlight focuses on the development of a supramolecular gel that can trap, protect, and release sensitive proteins without the need for additional excipients and cold-chain management. The third highlight explores the use of classical supramolecular binding events to improve the reliability of decoding synthetic digital polymers. The document also briefly mentions other advancements in the field, such as the development of multiply-switchable foldamers and the use of supramolecular guest binding in electrocatalytic reactions. [Extracted from the article]

A 30 year old man was found with no signs of life in front of the house. The cyanide concentration in blood and urine was determined five years after the man's death. What is more, a stability study was conducted for 730 days in an authentic casework blood sample. Sample preparation procedure included precipitation with methanol:water mixture, solid phase extraction (SPE) and derivatization with the use of PFB-Br (pentafluorobenzyl bromide). The sample was analyzed using GC-QqQ-MS/MS (gas chromatopraphy coupled with tandem mass spectrometry) isotope dilution method. Separation was done using a SH-RXI-5MS column (30 m x 0.25 mm, 0.25 µm). Detection of PFB-CN and PFB-13CN was achieved using a triple-quadrupole mass spectrometer with an electron ionization (EI) ion source in multiple reaction monitoring (MRM) mode. After 5 years from the man's death, cyanide concentration was: 1900 ng/mL in blood and 500 ng/mL in urine. Stability study performed in an authentic blood sample 6 and 7 years after the man's death revealed cyanide concentrations of 1898.2 ng/mL and 1618.7 ng/mL, respectively. While spectrophotometric and colorimetric methods recorded both decrease and increase in cyanide concentration over time, newer chromatographic methods mainly indicate a decrease. The studies presented in this paper seem to confirm this trend. However, in order to interpretate the results of cyanide concentration in biological material reliably, more research is still necessary. [ABSTRACT FROM AUTHOR]

A simple and convenient synthesis of 9-hydroxy[13C6]phenanthrene has been developed from one-ring labeled [13C6]phenanthrene in three steps, involving a copper-ethyl acetate catalyzed "Ullmann-type" reaction. The mild conditions of this nucleophilic aromatic substitution are particularly advantageous in the case of expensive labeled material. Stable-labeled 9-hydroxy[13C6]phenanthrene has proven to be an ideal [M + 6]isotopomer for use as an internal standard for quantification of OH-polycyclic aromatic hydrocarbons by gas chromatography with tandem mass spectrometry (GC-MS/MS) in human urines. [ABSTRACT FROM AUTHOR]

Polycystic ovarian syndrome (PCOS) is a commonly occurring reproductive disorder among the reproductive-aged women. Its global occurrence varies based on diagnostic guidelines, ethnicities, and locations of concern. Insulin resistance (IR) is commonly observed around 65–70% of women diagnosed with PCOS, representing a prevalent association. Consequently, the study was designed with an objective of illustrating the effect of insulin on mural and cumulus granulosa cells (GCs) of PCOS patients in comparison to normal ovulating women. This study is a case–control design, wherein a total of 80 participants were recruited meeting criterion of inclusion and exclusion, divided into 8 groups with each group consisting of 10 samples. The process involves the isolation and culturing of mural granulosa cells (MGC) and cumulus granulosa cells (CGC) with and without exposure to insulin. The proteins released by untreated GCs and insulin-treated GCs were extracted, and complex protein mixtures were digested with trypsin, followed by tandem mass spectrometry analysis and data processing using bioinformatics. We found 595 proteins in both control and PCOS samples, of which 310 were contributed by MGCs and 285 by CGCs. The PCOS MGCs expressed 20%, both the normal MGCs and CGCs have equal representation of 16% by each, whereas the PCOS CGCs proteins contributed 15% of the total of the proteomic expression. However, the poor expression observed with the Insulin exposure, the Insulin treated PCOS CGCs contributes 13%, PCOS MGCs contributes 8%. The normal MGCs upon the Insulin treatment give 8% then and there only 4% of proteins expressed by normal CGCs after Insulin treatment. The Venn analysis widened on their precise expression topographies. The examination of strings exhibited important protein–protein interaction pathways. This is a pioneering investigation aimed to establish the link between hyperinsulinemia in localized follicular GCs and PCOS mechanisms by comparing them to control group. The examination of various attributes, mechanisms, and traits shown by genes and proteins in individuals with PCOS compared to control populations, alongside the investigation of the dynamics of these genes and proteins following exposure to insulin, holds promise for the formulation of novel hypotheses and strategies in the identification of new biomarkers. [ABSTRACT FROM AUTHOR]

In humans, AMPylation of cellular proteins is carried out by Huntingtin yeast-interacting protein E (HYPE), activated under conditions of endoplasmic reticulum stress, such as in cancer cells. Extracts of the human chronic lymphocytic leukemia cell line, OSU-CLL, were fractionated using immuno-precipitation with antibodies against adenosine-phosphate and then AMP-Tyr. The proteins isolated were modified with AMP, the 'AMPylome.' AMP-labelled peptides isolated from HYPE wild-type (WT) and HYPE knock-out (KO) cells were identified using tandem mass spectrometry. A total of 213 proteins were identified from WT cell extracts, while only 23 of these were pulled down from KO cells, consistent with the presence of another AMPylator, besides HYPE. The KO cells were more sensitive to fludarabine nucleoside (2-FaraA) than WT cells. Ingenuity Pathway Analysis of the AMPylated proteins identified in WT cells clustered actin binding proteins of the cytoskeleton, and proteins of the RHO GTPase pathway that would jointly stimulate cell proliferation. [ABSTRACT FROM AUTHOR]

A rapid and simple magnetic solid phase extraction-liquid chromatography-tandem mass spectrometry method is reported to determine vancomycin in human plasma. The Fe3O4@SiO2 nanocomposite was prepared using silica nanoparticles obtained from rice husk waste and its modification using ammonia solution to obtain a Fe3O4@SiO2-NH2 nanohybrid as a new sorbent. The structure and morphology of the sorbent were characterized by X-ray diffraction, field emission scanning electron microscopy, and Fourier transform infrared spectroscopy. The nanosorbent was successfully used in magnetic solid phase extraction without hazardous solvents in 9 min with analysis by high-performance liquid chromatography – tandem mass spectrometry. Under the optimized conditions, the method provided a linear range from 10 to 1000 ng mL−1. The intra-day (n = 3) and inter-day precision (n = 3 working days) were below 10% relative standard deviation. The developed procedure was employed for determining vancomycin in human plasma with recoveries from 84.0 to 109.5% for spiked samples. [ABSTRACT FROM AUTHOR]

LN005 is a peptide–drug conjugate (PDC) targeting glucose-regulated protein 78 (GRP78) to treat several types of cancer, such as breast, colon, and prostate cancer. As a new drug modality, understanding its metabolism and elimination pathways will help us to have a whole picture of it. Currently, there are no metabolic studies on LN005; therefore, this study aimed to investigate the metabolism of LN005, clarify its metabolic profile in the liver S9s of different species, and identify the major metabolic pathways and differences between species. The incubation samples were measured by ultra-high performance liquid chromatography combined with orbitrap tandem mass spectrometry (UHPLC-Orbitrap-HRMS). The results showed that LN005 was metabolised by liver S9s, and four metabolites were identified. The main metabolic pathway of LN005 in liver S9s was oxidative deamination to ketone or hydrolysis. Similar metabolic profiles were observed in mouse, rat, dog, monkey, and human liver S9s, indicating no differences between these four animal species and humans. This study provides information for the structural modification and optimisation of LN005 and affords a reference for subsequent animal experiments and human metabolism of other PDCs. [ABSTRACT FROM AUTHOR]

Diamondoids form a molecular class of cage-like structures and serve as a link between small, cyclic hydrocarbons and bulk nanodiamonds. Comparisons have been made between the infrared spectra of diamondoids and unidentified infrared emission bands seen in the spectra of certain stars with circumstellar disks. It is also suggested that their radical cations may contribute to features in the largely unassigned diffuse interstellar bands due to their low ionisation energy and absorption in the visible range. However, the optical spectra of these cations have only recently begun to be measured experimentally, which is required for astronomical identification. Herein, we present the first optical spectrum of the 1-cyanoadamantane radical cation (C11H15N, AdaCN+) between 275 and 1200 nm. The spectrum is obtained by electronic photodissociation (EPD) of mass-selected ions generated by electron ionisation in a tandem mass spectrometer coupled to a cryogenic trap held at 5 K. Experimental results are interpreted by (time-dependent) density functional theory calculations. The dominant fragmentation channels are HCN loss at low energies and C4H6N loss at energies above 2.9 eV. The EPD spectrum reveals broad bands that are rationalised by lifetime broadening and Franck-Condon congestion arising from geometric changes upon excitation. The astrophysical implications are discussed. [ABSTRACT FROM AUTHOR]

Intramolecular radical and proton migration in the gas phase are important processes driving the dissociation reactions underlying common tandem mass spectrometry processes, such as collision-induced and electron-induced dissociation reactions (CID and ExD). Mechanistic insights in these processes requires experiments that probe the molecular structures of ions along the reaction pathways, usually combined with quantum-chemical calculations. The combination of ion trap mass spectrometry with IR laser spectroscopy, pioneered among others by Dieter Gerlich, provides a particularly effective method to explore details of the ion structures. In this work, we employ infrared multiple-photon dissociation (IRMPD) spectroscopy and density functional theory (DFT) calculations to probe the reactant and product ion structures of a homolytic bond cleavage reaction. First, we employ IRMPD spectroscopy to establish that protonation of the 4-bromoaniline precursor occurs on the amine moiety and then that C-Br homolytic cleavage produces the π-radical cation of aniline. Transition-state calculations are performed to compare the various pathways that connect reactant and product ions, including both proton and radical transfer mechanisms. [ABSTRACT FROM AUTHOR]

Three chromatographic procedures were investigated regarding their potential for the quantification of aniline and 19 of its methylated and chlorinated derivatives in groundwater. These methods were based on liquid-liquid-extraction in combination with gas chromatography and single quadrupole mass spectrometry (GC/MS) according to German standard DIN 38407–16:1999 and its extension using tandem mass spectrometry (GC/MS-MS), both following liquid–liquid extraction, and as third alternative the direct injection of the water sample into a liquid chromatograph coupled to tandem mass spectrometry (LC/MS-MS). Results were compared using fortified water and real-world contaminated groundwater used in an interlaboratory comparison. It could be shown that GC/MS and GC/MS-MS yielded results deviating less than 10% from each other, while all three procedures displayed quantification results deviating less than 15% from the intercomparison reference values in case of each analyte in the concentration range between 1 and 45 µg L−1. Though GC/MS-MS displays a ten-fold higher sensitivity than single quadrupole GC/MS, the precision of both methods in the concentration range was similar. LC/MS-MS has the advantage of no further sample preparation due to direct injection and leads for methylanilines and meta-, para-substituted chloroanilines to results sufficiently equivalent to the standardised GC/MS method. However, LC/MS-MS is not suitable for ortho-chloroaniline derivatives due to significantly lower ion yields than meta- and para-substituted chloroanilines. [ABSTRACT FROM AUTHOR]

An analytical method based on headspace solid-phase microextraction gas chromatography- ion trap tandem mass spectrometry (HS-SPME-GC-ITMS/MS) was optimised and developed for estimating 20 predominant polychlorinated biphenyl (PCB) concentrations in sediment samples. The effect of experimental parameters involving fibre materials, amount of water added, temperature effect, sorption time, stirring effect, and the addition of solvents were examined with gas chromatography-electron capture detector (GC-ECD). The analytical performance of association of HS-SPME-GC-ITMS/MS proposed methodology was examined by spiked sediment with the selected PCB congeners. The repeatability and reproducibility of measurements (n = 6), expressed with relative standard deviation (RSD), was below 13% and 16%, respectively. Good linearity was observed within the concentration range studied and the LODs were between 0.02 and 0.82 ng g−1. Accuracy was assessed by analysing a reference sediment sample with certified concentrations of several PCBs. Standard addition calibrations were done and concentrations of PCBs with the proposed method were in good agreement with the certified PCB concentrations. The method was also efficiently applied to real sample sediment from Bizerte Harbour, revealing the existence of several congeners at level less than 1.1 ng g−1. These obtained results were also on concordance with analysis of this real sample using a conventional soxhlet extraction method. The developed procedure is highly effective and selective, free of organic solvents, relatively simple and fast, and become a suitable alternative for routine monitoring of residues of PCB from sediments at ultra-trace levels. [ABSTRACT FROM AUTHOR]

Orange oil is considered the largest produced essential oils worldwide due to its unique properties. Pesticide residues in orange oil are expected to be much higher than the original fruit due to orange peel's cold-pressing during orange oil production. These residuesmaycause various health problems if consumed. The purpose of our study was to optimize and compare four multi-residues extraction methods (dilution, QuEChERS, ethyl acetate, and mini-Luke) for analysis of 387 pesticides in orange oil using LC-MS/MS and GC-MS/MS. To our knowledge, this is the first report on the use of ethyl acetate and the mini-Luke method for the analysis of orange oil. The comparison was based on recoveries, matrix effect, and the amount of co-extract matrix. The optimum mean recoveries were obtained by the ethyl acetate method, which successfully analyzes 371 out of 387 pesticides with acceptable recovery (70–120%). It also showed a narrow recovery distribution in the range of 90–110% for 69% of all studied pesticides. Regarding the matrix effect, the QuEChERS method gave the highest number of pesticides with an in significant matrix effect (80–120%) for both LC and GC amenable pesticides. The least amount of co-extract matrix components according to GC-MS/MS scan and gravimetric analysis has been achieved by the QuEChERS method. In conclusion, the Ethyl acetate method gives acceptable recovery for a wide range of pesticides with a narrow recovery distribution and a moderate amount of co-extract matrix. While the QuEChERS method provides better selectivity and cleaner extract but with a narrow scope and less precision. [ABSTRACT FROM AUTHOR]

The occurrence of pesticide residues, their metabolites and degradation products in 49 edible mushrooms (fresh, dried, canned and frozen) was investigated. Using QuEChERS extraction, followed by liquid and gas chromatography coupled with tandem mass spectrometry, the samples collected from Czech markets were tested for 427 analytes. A total of 21 pesticide residues, their metabolites and pesticide synergists were found in quantifiable concentrations. The most frequently detected pesticide residues included prochloraz and its metabolites, metrafenone and carbendazim. Two mushroom samples were found to be in violation of the maximum residue level. In addition, the fate of 13 pesticides during the processing of fresh mushrooms was investigated. The processing factors calculated from the data ranged from 6.0 to 12.3 for drying and from 0.3 to 1.3 for deep-freezing. The results showed that most of the pesticide residues tested were stable under the conditions of mushroom processing. [ABSTRACT FROM AUTHOR]

Illegal drugs are becoming a public health problem in African cities. In 2021, Bombé, a new drug of unknown composition, caused an outbreak of neuro-psychiatric symptoms in Kinshasa. Bombé was rumored to be based on ground catalytic exhausts stolen from cars. The chemical composition of six samples of Bombé obtained from different neighborhoods in Kinshasa was determined by triple quad liquid chromatography-mass spectrometry/mass spectrometry with confirmation by quadrupole time-of-flight mass spectrometry. Metals were determined by inductively coupled plasma-mass spectrometry, and polycyclic aromatic hydrocarbons were measured by gas chromatography-mass spectrometry. Analysis of the Bombé samples revealed that it contained heroin (2–12% of the total area under the curve of the samples) and opioid derivatives, plus paracetamol (33–72%), caffeine (17–26%), and also benzodiazepines (5/6 samples) and cyproheptadine (2/6 samples). The concentrations of neurotoxic metals were unremarkable. The median (range) concentrations of manganese and lead were 9.4 µg/g (range 3–334 μg/g) and 0.36 µg/g (range 0.1–3.12 μg/g), respectively. All polycyclic aromatic hydrocarbons were below the level of detection (<0.10 µg/g). Thanks to international collaboration, Bombé was documented to be a heroin-based drug and its alleged origin from catalytic exhausts was not substantiated. The local human expertise and technical capacity for undertaking toxicological analyses should be increased in Africa. [ABSTRACT FROM AUTHOR]

Metaldehyde consumption by pets and other mammals constitute medical emergencies ideally requiring rapid poison removal. The purpose of this study was three-fold: 1) development of a sensitive method for metaldehyde quantitation in patient serum samples by gas chromatography combined with tandem quadrupole mass spectrometry (GC/MS/MS); 2) development of a sensitive method for quantitation of the volatile metaldehyde metabolite acetaldehyde by headspace analysis combined with GC/MS/MS; and 3) an initial assessment of the efficacy of combined dialysis and hemoperfusion treatments in diminishing toxin loads in canine victims of metaldehyde poisoning. Both mass spectrometric approaches relied on Multiple Reaction Monitoring (MRM) methodologies. Metaldehyde extracted via liquid-liquid partitioning from serum was detected with a limit of quantitation (LOQ) of 7.3 ± 1.4 ng/mL with linearity in the range 1–250 ng/mL with accuracy improved by inclusion of a deuterated metaldehyde internal standard. Acetaldehyde was determined to have an LOQ of 0.39 μg/mL with linearity in the range 1–1000 μg/mL. The developed methodologies were applied to canine samples taken over various time points during dialysis treatment. Two of three canine patients showed significant abatement of metaldehyde levels by over 50-fold from initial concentrations while a third was shown to be negative with no measureable metaldehyde. The toxic metabolite acetaldehyde was found in one of the metaldehyde-poisoned patients and the detected acetaldehyde was also reduced by roughly 200-fold during the course of treatment. The designed mass spectrometric techniques were thus successful in demonstrating the efficacy of the applied dialysis-hemoperfusion methods which may find wider applicability against other potentially lethal toxins in poisoned patients in future studies. [ABSTRACT FROM AUTHOR]

Since antiquity, Centaurea species have been used in folk medicine to treat several diseases owing to their potential biological activities that distinguish this genus such as antioxidant, anticancer, and anti-inflammatory effect. The current study aimed to investigate the possible neuroprotective effects of the n-butanol extract of Centaurea maroccana (BECM) against cisplatin (CP) induced neurotoxicity in mice. BECM's potential neuroprotective properties were studied in vitro and in vivo models. Male Swiss albino mice were orally received BECM (200 mg/kg) for 10 days before a single intraperitoneal injection of cisplatin (8 mg/kg). Vitamin E (100 mg/kg) was given daily by gavage as a positive control. In vitro results revealed that BECM inhibited lipid peroxidation (LPO) levels and acetylcholinesterase (AChE) activity. In vivo findings showed that BECM pretreatment was able to regulate lactate dehydrogenase (LDH) levels and to improve CP-induced cholinergic dysfunction by inhibiting AChE activity in mice brains. Moreover, BECM attenuated CP-provoked oxidative stress by suppressing LPO levels, increasing total antioxidant capacity (TAC) and enhancing the activities of antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx) and glutathione S-transferase (GST)) in both brain cytosolic and mitochondrial fractions. The histological analysis exhibited neurotoprotective effect of BECM by protecting the cerebral cortex and reducing the histomorphological alterations resulted by cisplatin. Interestingly, our extract achieved neuroprotection comparable to vitamin E in most evaluated parameters. It appears that protective potency of BECM against CP-induced neurotoxicity could be related to its richness in polyphenols confirmed by liquid-chromatography tandem mass spectrometry analysis (LC-MS/MS). [ABSTRACT FROM AUTHOR]

Research on Polycyclic Aromatic Compounds (PACs) in the atmospheric environment has been mainly focused on the 16 EPA's PAHs. Due to toxicological relevance and particular emission sources, there is a research need in broadening the scope of PACs analysis to include polar and semi-polar PACs in new analytical methods. Here, we describe a single GC-MS/MS method to simultaneously determine 79 polar, semi-polar and non-polar PACs. Temperature gradient and injection conditions were optimized. Optimal Multiple Reaction Monitoring (MRM) and pseudo-MRM mass transitions were searched to enhance the detection. PACs were extracted from particulate samples by Pressurized Liquid Extraction (PLE). The choice of the optimal extraction solvent was carefully evaluated. Instrumental LOQ were from 1 to 2 ng. The method was validated against linearity of the calibration, intra-day and inter-day variability, LOQ and recoveries. The analysis of a Diesel Particulate Matter Certified Reference Material enabled a firm method validation. The method was applied to PM10 samples from a residential parking lot. PACs total amount varied from 2.3 to 14 ng/m3. The most abundant PACs were phthalic anhydride, 1,8-naphthalic anhydride and benzo(b)fluoranthene. PAHs diagnostic ratios enabled the identification of fuel combustion and vehicular traffic as the main source of PACs. [ABSTRACT FROM AUTHOR]

Background: Changes in cortisol binding globulin (CBG) impact the total serum cortisol concentration and affect the accurate assessment of adrenal function. Free biologically cortisol can be calculated using different equations or directly measured after complicated procedures. Methods: The free cortisol index (FCI) obtained using the Bonte formula as well as the free cortisol concentration calculated (Coolens equation) were first estimated for 45 healthy workers. The CBG level was determined by a competitive radioimmunoassay and the total cortisol concentration, was measured with an electrochemiluminescent assay. The correlations between FCI, the free cortisol concentrations calculated and the free cortisol levels measured with liquid chromatography-tandem mass spectrometry after equilibrium dialysis were studied for those 45 samples. Reference limits were established on 158 healthy hospital workers and patients with serum samples collected between 7:30 am and 10 am. Results: The FCI as well as the free cortisol concentrations calculated obtained for the 45 samples correlated significantly with the free cortisol levels measured. Although the cortisol and CBG levels were statistically higher in women using contraceptives compared with women not taking them as well as men, the calculated FCI and free cortisol concentrations did not differ between these groups. The medians (P2.5-P97.5) obtained for the 158 healthy workers were respectively 26.4% (12.3-51.6%) and 10.6 nmol/L (4.3-26.7 nmol/L). Conclusions: This study highlighted a significant correlation between the FCI, the free cortisol concentrations calculated and the free cortisol levels measured with LC-MS/MS, it has also allowed the establishment of reference intervals for calculated FCI and free cortisol. [ABSTRACT FROM AUTHOR]

The g-C3N4 (GCN) adsorbent with two different morphologies, coral (CGCN) and nano fiber (GCNNF), was synthesized and recruited for extraction and preconcentration of lead and copper metal ions by effervescent salt-assisted dispersive micro solid phase extraction procedure. The structures of the two adsorbents were affirmed by Fourier-transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy and Brunauer–Emmett–Teller analyses. The factors affecting the extraction efficiency were carefully studied and the optimum values of the parameters for both adsorbents were pH 6.5, adsorbent dosage 8 mg, desorption time 3 min, and the elution solvent 300 μL of 2 mol L−1 of HNO3. The detection limits of Pb(II (and Cu(II) ions for CGCN were 0.9 and 0.3 μgL−1 and for GCNNF were 1.56 and 0.7 μgL−1, respectively. The percent relative standard deviations were obtained to be 1.32% and 2.23% for CGCN (n = 3) and 1.24% and 2.29% for GCNNF (n = 3), respectively for the lead and copper metal ions. In addition, the adsorbents could be used up to 7 times without an imperative reduction in the percentages of analytes recovery. Finally, the performance of CGCN and GCNNF were used for preconcentrate of lead and copper ions in honey, canned fish, and human hair samples. [ABSTRACT FROM AUTHOR]

Tea (Camellia sinensis L.) is a high valued beverage worldwide since ancient times; more than three billion cups of tea are consumed each day. Leaf extracts of the plant are used for food preservation, cosmetics, and medicinal purposes. Nevertheless, tea contaminated with mycotoxins poses a serious health threat to humans. Mycotoxin production by tea fungi is induced by a variety of factors, including poor processing methods and environmental factors such as high temperature and humidity. This review summarizes the studies published to date on mycotoxin prevalence, toxicity, the effects of climate change on mycotoxin production, and the methods used to detect and decontaminate tea mycotoxins. While many investigations in this domain have been carried out on the prevalence of aflatoxins and ochratoxins in black, green, pu-erh, and herbal teas, much less information is available on zearalenone, fumonisins, and Alternaria toxins. Mycotoxins in teas were detected using several methods; the most commonly used being the High-Performance Liquid Chromatography (HPLC) with fluorescence detection, followed by HPLC with tandem mass spectrometry, gas chromatography and enzyme-linked immunosorbent assay. Further, mycotoxins decontamination methods for teas included physical, chemical, and biological methods, with physical methods being most prevalent. Finally, research gaps and future directions have also been discussed. [ABSTRACT FROM AUTHOR]

Interest in plant-based diets and vegetarianism is increasing worldwide, however, a concern for total vegetarians is vitamin B12 (B12) deficiency. We conducted a systematic review to investigate non-animal food sources of B12. Databases were PubMed, LILACS, Cochrane, Embase and Google Scholar, up to September 9, 2020. Quality of the eligible studies were assessed. We identified 25 studies which assessed B12 content in seaweeds, mushrooms, plants and fermented foods. Initial studies were microbiological bioassay, ELISA and HPLC. In the last decade, more sensitive method for real B12 determination was used, the liquid chromatography-electrospray ionization tandem mass spectrometry chromatograms. Real B12 content varied from mean (SD) mcg/portion size of seaweed hijiki 3 × 10−3/7 g to nori 1.03 − 2.68/sheet; mushroom white button cap 2 × 10−3(7 × 10−4)/20 g dry weight (dw) to shiitake 0.79(0.67)−1.12 (0.78)/20 g dw; and fermented foods from soy yogurt 20/cup. It is possible that daily recommendations for B12 can be met by a varied diet containing non-animal B12 food sources. Future research should consider different methods of storage, preparation, fermented foods and standardization of the production of certain foods. Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2022.2053057 [ABSTRACT FROM AUTHOR]

Bamboo and wood are widely used as food contact materials (FCMs). Fungicides are often applied during the manufacture of these products to prevent mildew; thus, monitoring for fungicide residues is essential because of the possible risks to food safety. However, it is not clear whether residual fungicides in treated bamboo and wood products migrate into food to cause harm to humans, and there is an absence of procedures for these analyses. In this study, the simultaneous determination of fungicides was validated in bamboo and wood FCMs by high-performance liquid chromatography–triple quadrupole tandem mass spectrometry (HPLC–MS/MS). The analytes were extracted with methanol or 1:1 methanol/acetonitrile and purified using 25 mg primary secondary amine adsorbent with 2.5 mg graphitized carbon black or 25 mg PSA with 25 mg octadecylsilane (C18). The recoveries for wood and bamboo FCMs were from 60.0% to 100.7% and 70.0% to 97.5%, respectively. The intra-day precision of wood and bamboo FCMs were from 0.1% to 5.3% and 0.1 to 3.0%, and the inter-day precision from 0.3% to 8.5% and 1.2% to 7.8%, respectively. The limits of detection ranged from 0.11 to 15.38 for wood and 0.25–6.19 μg kg−1 for bamboo. This method provides a reference for the determination of fungicides in bamboo and wood FCMs. [ABSTRACT FROM AUTHOR]

Although restricting environmental quality values for organotin compounds (OTs) are set by Directive 2013/39/EU of the European Parliament, marine environment remains being affected due to maritime circulation at global scale. Fish and seafood accumulate OTs, making fish and seafood consumption the main source of OTs in humans. Because of the fish and seafood matrices complexity and the required low limits of detection, a robust and fast procedure for the quantification of OTs in fish and seafood, using ultrasound-assisted extraction and gas chromatography–tandem mass spectrometry, was validated and applied. Detection (2.7 µg Sn kg−1) and quantification (8.0 µg Sn kg−1) limits, repeatability and intermediate precision (<10%), accuracy by analysing ERM®-CE477 Mussel Tissue and analytical recoveries (65–122%) were assessed. Multivariate analysis shown that the matrix effect for some OTs displayed good negative correlation with the fat and protein content. Health risk assessment of OTs intake revealed no serious risk for human consumption. [ABSTRACT FROM AUTHOR]

Gas chromatography – tandem mass spectrometry (GC-MS/MS) using formic acid as a protective agent is reported for the determination of acrylic resin monomers in food contact packaging paper. The analytes were extracted by ethanol mixed with formic acid with 2-phenylethyl propionate as the internal standard. The extract was separated by a 6% cyanopropylbenzene-94% dimethylsiloxane ultra-inert chromatographic column and analyzed by GC-MS/MS in multiple reaction monitoring (MRM) mode. 13 acrylic resin monomers including acrylic acid, styrene, and acrylic ester were separated. The procedure was successfully applied for the analysis of real samples. The procedure provided a linear calibration range with detection limits from 0.16 to 0.46 mg kg−1. The mean recoveries were from 88.1% to 100.9% with relative standard deviations less than 5.4%. The residual acrylic resin monomers in packaging paper were primarily from printing base paper and varnish. Of the acrylic resin monomers, the monomers except for butyl acrylate and 2-ethylhexyl acrylate showed low migration rates. The method provides high sensitivity and good reproducibility with simple pretreatment, demonstrating application for monitoring acrylic resin monomers in food contact packaging paper. [ABSTRACT FROM AUTHOR]

A paper spray tandem mass spectrometric (PS-MS/MS) method without column separation was developed for the rapid screening of clonidine in dietary supplements. PS-MS/MS provided acceptable performance compared to high-performance liquid chromatography – tandem mass spectrometry (HPLC-MS/MS) in terms of limits of detection and quantification, accuracy, and precision. To overcome ionization suppression of complicated plant-based pharmaceutical products, nizatidine, tizanidine, and apraclonidine were investigated as internal standards. A more similar structured internal standard is most suitable for matrix effect compensation. The developed method has advantages of simplicity and speed for the screening of clonidine in dietary supplements. [ABSTRACT FROM AUTHOR]

In this study, 135 samples of cocoa beans collected in the Amazon and Atlantic Forest regions of Brazil were analysed to evaluate the possible co-occurrence of 34 mycotoxins. The results indicate that 42% of the cocoa samples exhibited quantifiable levels for 11 mycotoxins: aflatoxins (AFs) B1, B2 and G1; ochratoxin A; citrinin; cyclopiazonic acid; tenuazonic acid; paxilline; sterigmatocystin; zearalenone and fumonisin B2. Of the samples, 18% exhibited the co-occurrence of up to six mycotoxins. No toxins belonging to the groups of trichothecenes or ergot alkaloids were detected. Contingency analysis of the incidence of mycotoxins did not show significant differences between the two regions evaluated. Seven samples were contaminated with AFs, while only one contained ochratoxin A above 10 μg kg−1. The accuracy of the method was evaluated by proficiency testing for ochratoxin A, where satisfactory Z-scores were obtained. [ABSTRACT FROM AUTHOR]

Flavonoids have been attracting increasing research interest because of their multiple health promoting effects. However, many flavonoids with similar structures are present in foods, often at low concentrations, which increases the difficulty of their separation and identification. Liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (LC-Q-TOF-MS/MS) has become one of the most widely used techniques for flavonoid detection. LC-Q-TOF-MS/MS can achieve highly efficient separation by LC; it also provides structural information regarding flavonoids by Q-TOF-MS/MS. This review presents a comprehensive summary of the scientific principles and detailed methodologies (e.g., qualitative determination, quantitative determination, and data processing) of LC-Q-TOF-MS/MS specifically for food flavonoids. it also discusses the recent applications of LC-Q-TOF-MS/MS in determination of flavonoid types and contents in agricultural products, changes in their structures and contents during food processing, and metabolism in vivo after consumption. Moreover, it proposes necessary technological improvements and potential applications. This review would facilitate the scientific understanding of theory and technique of LC-Q-TOF-MS/MS for flavonoid detection, and promote its applications in food and health industry. [ABSTRACT FROM AUTHOR]

The safety of medicinal herbs is critical to human health, and the monitoring of pesticide residues in medicinal herbs is necessary. In the present study, a direct competitive enzyme-linked immunosorbent assay (dc-ELISA) was developed for the determination of imidacloprid in medicinal herbs. Using the optimal conditions, the 50% inhibiting concentration and detection range (20–80% inhibiting concentration) of the established dc-ELISA were 0.08 and 0.03–0.29 ng/mL, respectively. Except for clothianidin (4.64%) and acetamiprid (2.52%), the cross-reactivity with analyte analogs was negligible. In purple perilla, cordate houttuynia, water lily, bitter melon, and mung bean, the average imidacloprid recoveries were from 62.97 to 134.09%, with relative standard deviations between 0.21 and 14.58%. Furthermore, the immunoassay results correlated well with spiked samples analyzed by high-performance liquid chromatography – tandem mass spectrometry (HPLC-MS/MS). The established immunoassay is rapid, sensitive, and specific and suitable to monitor imidacloprid residues in medicinal herbs. [ABSTRACT FROM AUTHOR]

Plastics- and rubber-derived chemicals are given increasing focus due to their migration into the environment and potential for causing detrimental effects. The current study demonstrates the use of a novel biomonitoring platform using caged fertilized eggs of lumpfish (Cyclopterus lumpus) in combination with gas chromatography tandem mass spectrometry analysis of a selection of target chemicals extracted from the lumpfish eggs after deployment. A monitoring campaign in the Trondheim harbor and off the coast of Trøndelag in Norway was executed using the described system. Here we found accumulation of UV stabilizers (benzophenone and benzothiazoles), plasticizers (n-butylbenzenesulfonamide), reagents, and polymer synthesis precursors (bisphenol A, acetophenone, phthalide, and phthalimide) in deployed eggs. Several of the compounds were detected in concentrations above previously quantified legacy contaminants in the same study areas. [ABSTRACT FROM AUTHOR]

A sensitive extraction and instrumental method was established to detect topramezone and its metabolite (M670H05) in maize and animal-origin foods. Two years of field experiments were carried out to study the dissipation dynamics of topramezone in maize straw, and their residue levels of actual samples collected from the supermarket were determined. They were extracted using liquid–liquid extraction (LLE), and ultra-high-performance liquid chromatography–tandem mass spectrometry was used for detection. The limit of quantification was 0.005 mg kg−1. Recoveries ranged between 73.8% and 109.9% at 3 spiking levels with intraday relative standard deviation (RSD) ≤17.7% and the inter-day ≤18.1%, which meets the requirements of SANTE/12682/2019. Dissipation dynamics experiment showed that, the deposition of topramezone in maize straw in Jilin were <0.005–0.62 mg kg−1with 28 days after application. And the residue level of market samples were all less than 0.005 mg kg−1, much lower than the MRLs (range from 0.01 to 0.8 mg kg−1) set by European Union, United States Food and Drug Administration, China, and Canada. This method was effective to analyse the residues of topramezone and M670H05. [ABSTRACT FROM AUTHOR]

The use of Moringa oleifera leaves as a poultry feed has been recognized worldwide, thanks to its multi-beneficial properties for broiler quality and production. However, research on the absorption and bioaccessibility of antioxidant compounds in this material is still limited. This study aims to investigate the effect of simulated poultry digestion on the bioaccessibility of quercetin 3-D-galactoside (Q3G) from Moringa leaf extracts and its antioxidant capacity via an in vitro model. Initially, a bio-guided fractionation procedure was employed to isolate Q3G and co-occurring antioxidants from Moringa leaves using column chromatography. The identification of Q3G and major phytocompounds within the potent active samples was carried out using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/ MS). The findings revealed that Q3G is predominantly present in the ethyl acetate extract of Moringa leaves, with the highest concentration recorded as 1.3 mg/g of dry weight. Via a simulated poultry digestion model, the bioaccessibility of Q3G in the small intestinal stage was calculated to have the highest proportion of 67.1%. Significantly, the change in Q3G content was in accordance with the tendency for antioxidant activity of the Q3G-included fractions throughout the digestion. The correlation analysis suggested that Q3G has an important role in the antioxidant capacity of Moringa leaf extracts. To the best of our knowledge, this study represents a pioneering attempt to investigate the bioaccessibility and antioxidant activity of Q3G and Q3G-included extracts from Moringa leaves, utilizing an in vitro poultry digestion model. The findings establish a crucial foundation for future research and development endeavors that aim to produce antioxidant supplements enriched with Q3G from natural sources for applications in poultry production. [ABSTRACT FROM AUTHOR]

Curry leaf is an evergreen herb with culinary, pharmaceutical, and nutraceutical applications. As pesticide residue in curry leaf has garnered significant regulatory attention in recent years, here we report a reliable method, which was validated for the determination of 265 and 225 pesticides using LC-MS/MS and GC-MS/MS, respectively. At first, the sample was comminuted after adding water (1:2). The sample preparation workflow included extraction of 10 g homogenized sample with 10 mL ethyl acetate (+1% acetic acid), cleanup by dispersive solid phase extraction (d-SPE, 50 mg PSA + 50 mg C18 + 10 mg GCB + 150 mg Na2SO4) and the final analysis by tandem mass spectrometry. The cleanup step adeptly removed co-extractives. The method effectively reduced matrix effects and offered an LOQ of 0.01 mg kg−1 for most compounds. The method's accuracy and precision results fulfilled the requirements of SANTE/11312/2021 guidelines at 0.01 mg kg−1 and higher levels of fortification. The accuracy and precision results were comparable for all pesticides. The successful screening of market samples indicates its high extraction efficiency and precision for incurred residue analysis. Due to its robustness and conformity with regulatory criteria, food testing laboratories worldwide can use the method to monitor pesticide levels in curry leaves. [ABSTRACT FROM AUTHOR]

This study was conducted to assess pesticide residues in 34 water and sediment samples taken from Kumkale Plain of Çanakkale-Turkey. Residue analyses were performed with the use of Quick-Easy-Cheap-Efficient-Rugged-Safe (QuEChERS)-liquid chromatography/tandem mass spectrometry (LC-MS/MS) procedure. For method verification, blank sediment and water samples were spiked at two limits of quantification (LOQ) levels of the pesticides. Overall recovery was 81.66% for sediment and 91.50% for water samples. In sediment samples, chlorpyrifos-M had the highest concentration, pyridaben was encountered in the majority of the samples (15 samples) and the highest number of pesticides (35) was seen in sample no. s13. In water samples, methoxyfenozide had the greatest concentration, metalaxyl was encountered in the highest number of samples (three samples) and the highest number of pesticide (8) was seen in sample no.w13. Sample no. s13 and w13 were taken from around the fountain basin. Pyraclostrobin and chlorantraniliprole residues exceeded the national limits set for water. In terms of hazard quotient (HQ), pesticides in sediment and waters were found to be safe. Despite the safe nature of pesticide on samples, greater attention has been paid on toxicity of the residues. It was concluded that authorities should put strict regulations on agrochemicals to reduce health risks of these chemicals. [ABSTRACT FROM AUTHOR]