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•Human and animals are exposed to mycotoxins on a daily basis.•The metabolic pathways and toxicokinetics of mycotoxins are complex.•Mycotoxins and their derivatives are related to ...different diseases.•HRMS is suitable for metabolomic studies of mycotoxins in biological samples.
Mycotoxins are toxic secondary metabolites produced by some filamentous fungi from Aspergillus, Fusarium, Penicillium, Alternaria and Claviceps genera. These metabolites are stable chemical compounds and persist during processing and heat treatment, so they can contaminate food and animal feed causing a broad spectrum of adverse effects both in humans and animals. In addition, mycotoxins can bioaccumulate in organs, and tissues, thereby affecting the nervous, endocrine, and immune systems; or can be excreted by biological fluids or faeces, being able to use as biomarkers of mycotoxin exposure. The most common are aflatoxins (B1, B2, G1, and G2), ochratoxin A, fumonisins, trichothecenes, zearalenone and patulin, although approximately 400 different mycotoxins have been described to date. Moreover, unaltered mycotoxins are not the only source of exposure since, as part of their defence against xenobiotics, plant and living organisms may alter their chemical structure.
Liquid chromatography (LC) coupled to tandem mass spectrometry (MS/MS) is commonly used for determining mycotoxins. However, not all mycotoxins or modified mycotoxins are commercially available as reference standards for use in monitoring, and, as a result, interest in high resolution mass spectrometry (HRMS) is increasing. More specifically, Orbitrap and time-of-flight (TOF) mass analysers have emerged as the most useful technique for mycotoxin determination. HRMS has important advantages over other methods, including the ability to record full scan spectra by measuring the accurate mass of analytes, the screening of untargeted compounds, a high degree of structural confirmation, and retrospective analysis data that offer the possibility of investigating analytes that were not considered at the time of spectral acquisition. This review discusses recent studies for the targeted and untargeted determination of mycotoxins in urine, blood and other relevant biological samples using strategies based on HRMS.
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•The first paper identifying and quantifying mycotoxins and metabolites in human breastmilk.•QuEChERS–UHPLC–HRMS allowed rapid and reliable quantitative analysis.•The exposure of ...mothers and infants to mycotoxins was evidenced using human milk.
Humans can be exposed to mycotoxins through the food chain. Mycotoxins are mainly found as contaminants in food and could be subsequently excreted via biological fluids such as urine or human breast milk in native or metabolised form. Since breast milk is usually supposed as the only food for new-borns, the occurrence of mycotoxins in thirty-five human milk samples was evaluated by a newly developed method based on QuEChERS extraction and UHPLC–HRMS detection. The method described here allows the detection of target mycotoxins in order to determine the quality of this initial feeding. The method has been fully validated, with recoveries ranging from 64% to 93% and relative standard deviations (RSD, %) being lower than 20%. Using the method described, non-metabolised mycotoxins such as ZEA, NEO, NIV, ENA, ENA1, ENB, ENB1 and metabolites, such as ZEA metabolites, HT-2, DOM and T-2 triol were detected in human milk samples. Results obtained help to estimate the exposure of mothers and infants to mycotoxins. Moreover, to the best of our knowledge, this is the first work describing the simultaneous detection, quantification and screening of mycotoxins and their metabolites in human mature milk.
•“Tranq-dope”, xylazine-adulterated opioids, has caused many overdose deaths in the US.•Xylazine and opioids act in synergy, increasing the lethality of one another.•We report the first fatal case of ...xylazine-adulterated heroin in the EU.•Xylazine and its main metabolite were detected in blood and urine by LC-HRMS/MS.•Xylazine should be strictly controlled by public health authorities and toxicologists.
The number of xylazine-involved overdose deaths tremendously increased from 2019 onwards in the US. This is due to the “tranq-dope” trend consisting in mixing opioids with the sedative to reduce drug manufacturing costs and enhance their effects. In this study, we report the first fatality involving xylazine-adulterated heroin in the EU.
The subject was a 33-year-old Caucasian male with a documented history of drug abuse who was found dead in a public area with puncture marks at the elbow. Peripheral blood and urine were collected at the autopsy and analyzed by liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS/MS) after protein precipitation.
6-Monoacetylmorphine, total/free morphine, and codeine blood concentrations of 20.3, 236/105, and 38.3 ng/mL, respectively, indicated recent heroin consumption. Methadone blood concentration was below 10 ng/mL. Alprazolam, nordiazepam, and flurazepam blood concentrations were 23.9, 61.4, and 55.0 ng/mL, respectively. Benzoylecgonine blood concentration was below 5 ng/mL. Xylazine blood and urine concentrations were 105 and 72.6 ng/mL, respectively.
The combination of central nervous system depressants, i.e., opioids, benzodiazepines, and xylazine, was the principal cause of death by cardiorespiratory failure. The case was promptly reported to the UE Early Warning System on drugs.
This review summarizes the advances in environmental analysis by liquid chromatography–high-resolution mass spectrometry (LC–HRMS) during the last decade and discusses different aspects of their ...application. LC–HRMS has become a powerful tool for simultaneous quantitative and qualitative analysis of organic pollutants, enabling their quantitation and the search for metabolites and transformation products or the detection of unknown compounds. LC–HRMS provides more information than low-resolution (LR) MS for each sample because it can accurately determine the mass of the molecular ion and its fragment ions if it can be used for MS–MS. Another advantage is that the data can be processed using either target analysis, suspect screening, retrospective analysis, or non-target screening. With the growing popularity and acceptance of HRMS analysis, current guidelines for compound confirmation need to be revised for quantitative and qualitative purposes. Furthermore, new commercial software and user-built libraries are required to mine data in an efficient and comprehensive way. The scope of this critical review is not to provide a comprehensive overview of the many studies performed with LC–HRMS in the field of environmental analysis, but to reveal its advantages and limitations using different workflows.
Dissolved organic nitrogen (DON) is actively involved in N cycling and transformation processes in the ocean, yet how this large N pool is formed remains elusive. Here we incubated 15N‐labeled ...individual amino acids (Ala, Val, and Phe) in seawater and monitored their fates over 21 days. About 25%–45% of Phe‐N and Val‐N were transformed to “uncharacterizable DON,” as compared to only about 6% for Ala‐N, indicating the formation of refractory DON is related to specific amino acids. Through a stable isotope probing approach, 5 Phe‐derived DON molecules from the incubations were found to be present in natural waters, and their possible structures were proposed. These results shed new lights on the formation mechanisms of refractory DON, including the roles of specific amino acids and particular chemical structures that may resist decomposition in millennial time scales.
Plain Language Summary
The formation of refractory dissolved organic nitrogen through microbial degradation was investigated through a series of lab incubations using amino acids as substrates. We found that a higher fraction of nitrogen (25%–45%) from phenylalanine and valine was transformed into refractory dissolved organic nitrogen, as compared to alanine (6%). Such contrasting results suggest that the formation of refractory dissolved organic nitrogen may be tightly connected with specific amino acids. We also constructed a database with possible structures of the amino acids‐derived dissolved organic nitrogen molecules based on stable isotope and high‐resolution mass spectrometry techniques. With the database, we further confirmed that at least five of amino acids‐derived dissolved organic nitrogen molecules were present in natural waters (including the deep ocean). Overall, our study offered new insights into the formation mechanisms of refractory dissolved organic nitrogen, demonstrating the roles of specific amino acids and particular chemical structures in the long‐term stability of dissolved organic nitrogen in the ocean.
Key Points
More nitrogen from phenylalanine or valine formed uncharacterizable dissolved organic nitrogen (DON) via microbial processing than that from alanine
Stable isotope probing coupled with advanced mass spectrometry was applied to build a database of amino acid‐derived DON molecules
Some DON molecules derived from phenylalanine are also present in natural waters
Gas chromatography coupled to high‐resolution mass spectrometry is a powerful analytical method that combines excellent separation power of gas chromatography with improved identification based on an ...accurate mass measurement. These features designate gas chromatography with high‐resolution mass spectrometry as the first choice for identification and structure elucidation of unknown volatile and semi‐volatile organic compounds. Gas chromatography with high‐resolution mass spectrometry quantitative analyses was previously focused on the determination of dioxins and related compounds using magnetic sector type analyzers, a standing requirement of many international standards. The introduction of a quadrupole high‐resolution time‐of‐flight mass analyzer broadened interest in this method and novel applications were developed, especially for multi‐target screening purposes. This review is focused on the development and the most interesting applications of gas chromatography coupled to high‐resolution mass spectrometry towards analysis of environmental matrices, biological fluids, and food safety since 2010. The main attention is paid to various approaches and applications of gas chromatography coupled to high‐resolution mass spectrometry for non‐target screening to identify contaminants and to characterize the chemical composition of environmental, food, and biological samples. The most interesting quantitative applications, where a significant contribution of gas chromatography with high‐resolution mass spectrometry over the currently used methods is expected, will be discussed as well.
Heterocyclic aromatic amines, as a group of mutagenic and carcinogenic compounds, have gained worldwide concern. In this study, an accurate, rapid, and sensitive confirmation and quantification ...method of four major heterocyclic aromatic amines in roasted pork was developed based on Q‐Orbitrap along with Quick, Easy, Cheap, Effective, Rugged, and Safe extraction. The limit of detections and limit of quantitations were found to be 0.2–1.2 μg/kg and 0.6–3.5 μg/kg, respectively, revealing the high sensitivity of this method. Obtained results showed recoveries ranging from 78.1 to 97.4%, depending on the different heterocyclic aromatic amines and spiked levels. Precision was in the range of 2.6–4.5% for four heterocyclic aromatic amines at different levels. In addition, the developed method had been applied to investigate the inhibitory effects of astaxanthin on the above‐mentioned heterocyclic aromatic amines in roasted pork. The amount of astaxanthin with the best inhibitory effects was 7.5 mg (0.0375%), which led to significant reduction in heterocyclic aromatic amines levels over 50%.
Database-driven suspect screening has proven to be a useful tool to detect new psychoactive substances (NPS) outside the scope of targeted screening; however, the lack of retention times specific to ...a liquid chromatography (LC) system can result in a large number of false positives. A singular stream-lined, quantitative structure-retention relationship (QSRR)-based retention time prediction model integrating multiple LC systems with different elution conditions is presented using retention time data (n = 1281) from the online crowd-sourced database, HighResNPS. Modelling was performed using an artificial neural network (ANN), specifically a multi-layer perceptron (MLP), using four molecular descriptors and one-hot encoding of categorical labels. Evaluation of test set predictions (n = 193) yielded coefficient of determination (R2) and mean absolute error (MAE) values of 0.942 and 0.583 min, respectively. The model successfully differentiated between LC systems, predicting 54%, 81% and 97% of the test set within ±0.5, ±1 and ±2 min, respectively. Additionally, retention times for an analyte not previously observed by the model were predicted within ±1 min for each LC system. The developed model can be used to predict retention times for all analytes on HighResNPS for each participating laboratory's LC system to further support suspect screening.
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•A retention time prediction model was developed incorporating multiple LC systems.•The model was trained using the retention times of new psychoactive substances.•Retention times were obtained from the crowd-sourced database, HighResNPS.•A singular model demonstrated improved performance over individual models.•The model can be used to predict retention times for unique entries on HighResNPS.
This study presents the validation of a sensitive method for the determination of 6‐nitrodopa, 6‐nitrodopamine, 6‐nitroadrenaline and 6‐cyanodopamine in Krebs–Henseleit solution by LC–MS/MS with ...ESI+. HRMS was used to precisely characterize the structures of the fragment ions. The method was applied to investigate the catecholamine basal release from rabbit isolated atria and ventricles. The atria and ventricles were suspended separately in a 5 ml organ bath containing Krebs–Henseleit solution with ascorbic acid (3 mM), gassed (95%O2/5%CO2) at 37°C for 30 min. Strata‐X 33 μm SPE cartridges were employed for the extraction of the catecholamines and the internal standard 6‐nitrodopamine‐d4. The catecholamines were separated employing a 150 × 3 mm Shim‐pack GIST C18‐AQ (3 mm particle size), placed in an oven at 40°C and perfused by 65% of mobile phase A (MeCN/H2O; 90/10, v/v) + 0.4% CH3COOH and 35% mobile phase B (deionized H2O) + 0.2% CH2O2 at 320 μl/min in isocratic mode. The method was linear at 0.1–20 ng/ml. The method was used to identify for the first‐time basal release of the three nitrocatecholamines mentioned above and a member of a novel class of catecholamines, the cyanocatecholamines.
Lipids are vital biological molecules and play multiple roles in cellular function of mammalian organisms such as cellular membrane anchoring, signal transduction, material trafficking and energy ...storage. Driven by the biological significance of lipids, lipidomics has become an emerging science in the field of omics. Lipidome in biological systems consists of hundreds of thousands of individual lipid molecules that possess complex structures, multiple categories, and diverse physicochemical properties assembled by different combinations of polar headgroups and hydrophobic fatty acyl chains. Such structural complexity poses a huge challenge for comprehensive lipidome analysis. Thanks to the great innovations in chromatographic separation techniques and the continuous advances in mass spectrometric detection tools, analytical strategies for lipidomics have been highly diversified so that the depth and breadth of lipidomics have been greatly enhanced. This review will present the current state of mass spectrometry-based analytical strategies including untargeted, targeted and pseudotargeted lipidomics. Recent typical applications of lipidomics in biomarker discovery, pathogenic mechanism and therapeutic strategy are summarized, and the challenges facing to the field of lipidomics are also discussed.
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•Recent advances in analytical techniques allow rapid, reliable and sensitive detection of hundreds to thousands of lipids•The diversified MS-based analytical strategies have greatly enhanced the development and application of lipidomics.•The integration of multi-omics has a bright prospect in studying the pathogenesis and potentially targetable therapy.•Comprehensive analysis of the lipidome still faces considerable challenges in analytical techniques.
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