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In our modern society, the drugs consumption is constantly increasing and is involving younger consumers. The Belgian lax is considering, among the drugs, compounds such as amphetamine derivatives, morphine, cocaine and cannabinoids. Many method of quantification in blood and urine are published in the scientific literature, but as the window for detection of narcotics in these biological fluids is relatively short, it is not easy to assess whether their use is chronic or occasional. Based in this observation, we developed the simultaneous determination of these drugs, with the exception of cannabinoids, in hair by LC-MSMS. Hairs are a biological matrix of interest, given the very good stability of the compounds in the hair structure. They also can allow assessing the history of consumption through growth of about 1 cm per month.
The drugs are extracted with methanol in the presence of their deuterated analogues. Then, a step clean-up is conducted through a column Solid Phase Extraction (SPE) MCX© from Waters®.
Our analytical validation reported extraction yields ranging from 59 to 157%, ions suppression or enhancement effects (matrix effect) between 1 and 55% accuracy between 70 and 115%, precision with CV≤15%, absence of carry-over, linearities with R²>0.98, and limits of detection and quantification, respectively, from 0.02273 to 0.5762 and 0.075 to 2.05 ng/mg of hair, for the different drugs tested.
The potential impact of hair treated with staining on the matrix effects and yields has been further assessed, without significant effect. Dans notre société moderne, la consommation de drogues est en perpétuelle augmentation et doit faire face à des consommateurs de plus en plus jeunes. La loi belge classe, parmi les stupéfiants, les composés tels que les dérivés amphétaminiques, morphiniques, la cocaïne ainsi que les cannabinoïdes. De nombreuses méthodes de quantification dans le sang et les urines sont publiées dans la littérature scientifique mais comme la fenêtre de détection des stupéfiants dans ces milieux est relativement courte, il n’est pas aisé d’évaluer si leur usage est chronique ou ponctuel. Partant de ce constat, nous avons mis au point le dosage simultané de ces drogues, à l’exception des cannabinoïdes, dans les cheveux par LC-MSMS. Les cheveux constituent une matrice biologique d’intérêt, vu la très bonne stabilité des substances dans la structure du cheveu. Ils permettent également d’établir un historique de consommation grâce à leur croissance d’environ 1cm par mois.
Les stupéfiants sont extraits avec du méthanol en présence de leurs homologues deutérés. Ensuite, une étape de clean-up est réalisée au moyen d’une colonne Solid Phase Extraction (SPE) MCX© de chez Waters®.
Notre validation analytique a évalué les rendements d’extraction allant de 59 à 157%, les effets de suppression ou d’augmentation d’ions (effet matrice) compris entre 1 et 55%, l’exactitude entre 70 et 115%, la précision avec des CV≤15%, une absence de carry-over, des linéarités avec des R²> à 0,98 et enfin les limites de détection et de quantification allant respectivement de 0,02273 à 0,5762 et 0,075 à 2,05 ng/mg de cheveux, pour les différentes drogues testées.
Pour compléter, nous avons aussi voulu évaluer l’impact potentiel des cheveux ayant subi un traitement par coloration sur les effets de matrice et les rendements

Narcotics --- Drug Users --- Chromatography, Liquid --- Tandem Mass Spectrometry --- Hair --- Hair --- Narcotics

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With the development of new quantitative strategies and powerful bioinformatics tools to cope with the analysis of the large amounts of data generated in proteomics experiments, liquid chromatography with tandem mass spectrometry (LC-MS/MS) is making possible the analysis of proteins on a global scale, meaning that proteomics can now start competing with cDNA microarrays for the analysis of whole genomes. In LC-MS/MS in Proteomics: Methods and Applications, experts in the field provide protocols and up-to-date reviews of the applications of LC-MS/MS, with a particular focus on MS-based methods of protein and peptide quantification and the analysis of post-translational modifications. Beginning with overviews of the use of LC-M/MS in protein analysis, the book continues with topics such as protocols for the analysis of post-translational modifications, with particular focus on phosphorylation and glycosylation, popular techniques for quantitative proteomics, such as multiple reaction monitoring, metabolic labelling, and chemical tagging, biomarker discovery in biological fluids, as well as novel applications of LC-MS/MS. Written in the highly successful Methods in Molecular Biology™ series format, chapters include introductions to their respective subjects, lists of necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and notes on troubleshooting and avoiding known pitfalls. Comprehensive and cutting-edge, LC-MS/MS in Proteomics: Methods and Applications presents the techniques and concepts necessary in order to aid proteomic practitioners in the application of LC-MS/MS to essentially any biological problem.

Biochemistry. --- Proteomics. --- Chromatography. --- Biochemistry, general. --- Protein Science. --- Molecular biology --- Proteins --- Biological chemistry --- Chemical composition of organisms --- Organisms --- Physiological chemistry --- Biology --- Chemistry --- Medical sciences --- Analysis, Chromatographic --- Chromatography --- Chemistry, Analytic --- Phase partition --- Composition --- Analytical chemistry --- Proteomics --- Liquid chromatography --- Tandem mass spectrometry

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In recent years, the interest in magnesium and in microelements in older people has exponentially increased. The deficiency of either magnesium and microelements, in fact, is associated with several negative outcomes in older people. Therefore, in this book, we decided to report the most novel and important research findings regarding these important topics. In particular, authoritative authors in the field of nutritional research in older people reported their experience in magnesium research, including articles on metabolic and cardiovascular aspects of magnesium deficiency. Moreover, we speculated the importance of magnesium in infectious diseases, including COVID-19. In this book, we also report some important findings regarding other microelements, such as iron and sodium or potassium, extremely important in older people.

magnesium --- proteomics --- randomized trial --- vitamin D --- liquid chromatography—tandem mass spectrometry --- post-menopause --- aging --- Alzheimer’s disease --- iron metabolism --- multiple sclerosis --- Parkinson’s disease --- sex differences --- stroke --- dementia --- cognitive decline --- cardiovascular disease --- hypertension --- older people --- sodium --- potassium --- malnutrition --- SarcoPhAge --- macronutrients --- micronutrients --- muscle strength --- physical performance --- gait speed --- ions --- insulin resistance --- diet --- supplement --- oxidative stress --- inflammation --- infectious diseases --- COVID-19 --- n/a --- liquid chromatography-tandem mass spectrometry --- Alzheimer's disease --- Parkinson's disease

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Glyphosate (N-(phosphonomethyl)glycine) is the most used herbicide worldwide. It exhibits all the advantages of the perfect herbicide : it is universal in the way it targets an enzyme present in all plants as well as algae and numerous microorganisms; but not animals, making its acute toxicity very low for human and fauna, its mobility in soil has long been regarded as negligible, it is degraded by UV light (including sunlight) and bacteria commonly found in soils, it allows to limit ploughing and thus to promote soil conservation by reducing erosion; and, above all, it also has the tremendous advantage to spare genetically modified resistant crops, providing a huge financial benefits and allowing to reduce the use of other more toxic herbicides as well as the carbon footprint through reduced use of agricultural machinery.
However, the decades-long debate on its carcinogenicity has been reignited in 2015 when the International Agency for Research on Cancer classified glyphosate as “possibly carcinogenic to humans” (category 2A). The chronic effects of glyphosate and its main metabolite, aminomethylphosphonic acid (AMPA), (i.e. carcinogenicity, mutagenicity, endocrine disruptor potency...) are a real concern knowing that glyphosate is so widely used that the two contaminants , and mostly the more mobile AMPA, has been shown to reach water tables and to become ubiquitous in soils, water streams and sewage. Indeed, the molecule has been shown to be quite persistent in water and soils in a certain number of conditions of composition, weather and bacterial communities. Glyphosate metabolization in plants is vastly recognized as low or negligible, which suggest that genetically modified resistant crops might thus accumulate the herbicide until consumption. Finally, a few studies and even instances of the World Health Organization have been starting to suggest that the negative effects of glyphosate on health -through the studies of bees exposed to the herbicide- could be due to its supposed harmful effect on beneficial intestinal microbiota. All of these considerations make the accurate monitoring of glyphosate and AMPA in the environment, drinking water and food commodities a public health and environmental priority.
The routine analysis of highly polar pesticide has always been challenging in liquid chromatography since these compounds are not compatible with the QuEChERS solid phase extraction associated with reversed phase liquid chromatography, commonly used in multiresidue analysis, nor normal phase liquid chromatography. Yet many popular pesticides fall into this category, including glyphosate and its metabolite, AMPA.
So far, the methods used for quantification of glyphosate and AMPA involved a derivatization step and day-long manipulations that may be regarded as tedious. In this work was a quick, cheap and effective direct determination method for glyphosate and AMPA in sugar beet root using an Hydrophilic Interaction Liquid Chromatography (HILIC) column with a diethylamine stationary phase fit for retention and separation of highly polar anionic compounds; based on the QuPPe-PO extraction method from the European Reference Laboratories for Single Residue Methods (EURL-SRM) and validated in accordance to the requirements in force at the BEAGx and the SANTE/12682/2019 guidelines.
The chosen matrix was sugar beet root. In the E.U., as resistant GM sugar beet are not approved for cultivation, glyphosate is only used for clearing weeds before sowing. However, in the U.S., almost all cultivated sugar beets are GM glyphosate-resistant crops, treated with the herbicide up to three times during cultivation. They are allowed for importation, food and feed use in the E.U., as well as their derived products and by-products. And as European public opinion on glyphosate is deteriorating, countries are progressively removing the active substance from the shelves for domestic users while countries are debating national bans, stakeholder of the sugar industry across Europe are increasingly willing to be able to monitor glyphosate residues in their raw material, products and by-products to prevent any public health crisis or scandal that could be detrimental to their sector. Le glyphosate (N-(phosphonométhyl)glycine) est l’herbicide le plus utilisé au monde. Il présente tous les avantages de l’herbicide parfait : il est universel dans sa manière de cibler une enzyme présente dans tous les végétaux, les algues et de nombreux microorganismes ; mais pas les animaux, rendant sa toxicité aiguë très faible pour la faune et l’humain, sa mobilité dans les sols a longtemps été considérée négligeable, il est dégradé par la lumière ultraviolette (incluant la lumière solaire) et des bactéries communes dans les sols, il permet de limiter le labour et ainsi de favoriser la conservation des sols en réduisant l’érosion; et, par-dessus tout, il a aussi l’énorme avantage d’épargner les cultures résistantes génétiquement modifiées, fournissant un énorme avantage financier et permettant de réduire l’utilisation d’autres herbicides plus toxiques ainsi que l’empreinte carbone par la réduction de l’utilisation de machines agricoles.
Cependant, le long débat sur sa cancérogénicité a été relancé en 2015 lorsque le Centre international de recherche sur le cancer a classé le glyphosate comme "potentiellement cancérigène pour l'homme" (catégorie 2A). Les effets chroniques du glyphosate et de son principal métabolite, l'acide aminométhylphosphonique (AMPA), (c'est-à-dire sa cancérogénicité, sa mutagénicité, son potentiel en tant que perturbateur endocrinien...) sont une réelle préoccupation sachant que le glyphosate est si largement utilisé qu'il a été démontré que les deux contaminants, et surtout l’AMPA qui est plus mobile, atteignent les nappes phréatiques et deviennent omniprésents dans les sols, les cours d'eau et les eaux usées. En effet, il a été démontré que la molécule est assez persistante dans l'eau et les sols dans un certain nombre de conditions de composition, de temps et de communautés bactériennes. La métabolisation du glyphosate dans les plantes est largement reconnue comme faible ou négligeable, ce qui suggère que les cultures génétiquement modifiées résistantes pourraient ainsi accumuler l'herbicide jusqu'à leur consommation. Enfin, quelques études et même des instances de l'Organisation mondiale de la santé ont commencé à suggérer que les effets négatifs du glyphosate sur la santé - notamment à travers les études sur les abeilles exposées à l'herbicide - pourraient être dus à son effet nocif supposé sur le microbiote intestinal bénéfique. Toutes ces considérations font de la surveillance précise du glyphosate et de l'AMPA dans l'environnement, l'eau potable et les produits alimentaires une priorité de santé publique et environnementale.
L’analyse de routine de pesticides hautement polaires a toujours été difficile en chromatographie liquide compte tenu que ces composés ne sont pas compatibles avec l’extraction en phase solide QuEChERS associée à la chromatographie liquide en phase inverse, couramment utilisée en analyse multi-résidus, ni avec la chromatographie liquide en phase normale. Pourtant, de nombreux pesticides populaires font partie de cette catégorie, y compris le glyphosate et son métabolite, l’AMPA.
Jusqu’à présent, les méthodes utilisées pour la quantification du glyphosate et de l’AMPA, impliquaient une étape de dérivatisation et des manipulations durant une journée entière pouvant être considérée comme fastidieuses. L’objectif de ce travail a été de développer une méthode rapide, peu coûteuse et efficace de détermination directe du glyphosate et de l’AMPA dans la betterave sucrière en utilisant une colonne de Chromatographie Liquide d’Interaction Hydrophile (HILIC) avec une phase stationnaire diéthylamine adaptée à la rétention et à la séparation de composés anioniques hautement polaires; sur la base de la méthode d’extraction QuPPe-PO des Laboratoires Européens de Référence pour les Méthodes monorésidus (EURL-SRM) et validée au regard des exigences en vigueur au BEAGx et dans les directives SANTE/12682/2019.
La matrice choisie a été la betterave sucrière. Dans l'Union européenne, la culture de betteraves sucrières résistantes génétiquement modifiées n’est pas autorisée, le glyphosate est uniquement utilisé pour éliminer les mauvaises herbes avant les semis. Toutefois, aux États-Unis, presque toutes les betteraves sucrières cultivées sont des cultures OGM résistantes au glyphosate, traitées avec cet herbicide jusqu'à trois fois durant leur culture. L’importation, l’utilisation pour l'alimentation humaine et animale de celles-ci est autorisée dans l’U.E., ainsi que leurs produits dérivés et sous-produits. À mesure que l'opinion publique européenne sur le glyphosate se détériore, que les pays retirent progressivement la substances actives des rayons pour l’usage domestique et tandis que les pays débattent des interdictions nationales, les parties prenantes de l'industrie sucrière en Europe sont de plus en plus désireuses de pouvoir surveiller les résidus de glyphosate dans leurs matières premières et leurs produits et sous-produits afin d'éviter toute crise de santé publique ou tout scandale pouvant nuire à leur secteur.

Glyphosate --- AMPA --- Sugar beet --- HILIC --- Underivatized --- Liquid Chromatography --- MS/MS --- Tandem Mass Spectrometry --- Direct --- Direct analysis --- Underivatised --- LC --- LC-MS/MS --- QuPPe-PO --- Glyphosate --- AMPA --- Betterave sucrière --- HILIC --- Directe --- Sans Dérivatisation --- Chromatographie Liquide --- LC --- LC-MS/MS --- Spectrométrie de masse en tandem --- Analyse Directe --- QuPPe-PO --- Physique, chimie, mathématiques & sciences de la terre > Chimie --- Sciences du vivant > Sciences des denrées alimentaires

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Since its early introduction by the Russian botanist Mikhail Semyonovich Tsvet, chromatography has been undoubtedly the most powerful analytical tool in analytical chemistry. Separation, qualitative analysis, and quantitative analysis can be achieved by choosing the right conditions. Thus, numerous gas chromatographic, liquid chromatographic, and supercritical fluid chromatographic methods have been developed and applied for most types of samples and most kinds of analytes. Additionally, older varieties such as paper chromatography and thin-layer chromatography were pioneer analytical techniques in many laboratories. Especially when hyphenated to spectrometric techniques, chromatography also allows the identification of separated analytes in a single run. Highly sophisticated equipment can answer all analytical problems very quickly. Chromatographers cooperate with many scientific fields and give their lights to medical doctors, veterinarians, food scientists, biologists, dentists, archaeologists, etc. In this Special Issue, analytical chemists were invited to prove that chromatography-based separation techniques are the ultimate analytical tool and their significant contribution is reflected in ten interesting articles.

polyamine --- steroid --- breast cancer --- liquid chromatography–tandem mass spectrometry --- serum --- photoaging --- proteomics --- genomics --- Swietenia macrophylla --- UV irradiation --- keratinocytes --- epidermal layer --- cosmetics --- natural product --- LC-MS/MS --- metabolomics --- targeted analysis --- nontargeted analysis --- sample preparation --- derivatization --- validation --- biomarkers --- mycophenolate mofetil --- mycophenolic acid --- pediatric patients --- limited sampling strategy --- multiple linear regression --- therapeutic drug monitoring --- almonds --- HPLC --- authenticity --- PCA --- tocopherols --- phenolics --- method validation --- Miang --- catechins --- caffeine --- gallic acid --- walnut septum --- UAE --- SPE --- flavonoids --- functional --- HPLC-DAD --- biotin acceptor peptide (BAP) --- biotin ligase BirA --- liquid chromatography tandem mass spectrometry (LC-MS/MS) --- multiple reaction monitoring (MRM) --- protein–protein interactions (PPIs) --- proximity utilizing biotinylation (PUB) --- greener HPTLC --- paracetamol --- simultaneous determination --- microflow LC-MS --- mLC-MS/MS --- liver fibrosis --- hemopexin --- biomarker