Bibliographies thématiques / GC-HRMS Orbitrap

Littérature scientifique sur le sujet « GC-HRMS Orbitrap »

Auteur : Grafiati

Publié le 4 mai 2024

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Articles de revues sur le sujet "GC-HRMS Orbitrap"

Dahibhate, Nilesh Lakshman, et Kundan Kumar. « Metabolite profiling of Bruguiera cylindrica reveals presence of potential bioactive compounds ». PeerJ Analytical Chemistry 4 (4 mai 2022) : e16. http://dx.doi.org/10.7717/peerj-achem.16.

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Bruguiera cylindrica parts are commonly used in Chinese and Indian traditional medicine to treat diarrhea, fever, and many ailments. The present study aims non targeted analysis of key secondary metabolites of B. cylindrica by gas chromatography mass spectrometry (GC-MS) and ultra-high performance liquid chromatography hybrid quadrupole-Exactive-Orbitrap high resolution mass spectrometry (UHPLC-Q-Exactive Orbitrap HRMS). GC-MS and UHPLC-Q-Exactive Orbitrap HRMS were utilized for metabolic profiling of ethyl acetate extract of B. cylindrica leaves. Key metabolites in the extract were identified and predicted based on chemical similarity using online databases such as ChemSpider and mzCloud. Thirty-six compounds belonging to different classes of secondary metabolites viz. flavonoids, fatty acids, fatty acid amides, carboxylic acids, and alkaloids were identified in the extract. Pentacyclic triterpenes like betulin, ursolic acid and a tropine, an alkaloid with potential pharmacological and therapeutic activities such as anticancer properties, neuromuscular blockers and antioxidants, were also identified. This study combined GC-MS and UHPLC-Q-Exactive Orbitrap HRMS with available online database for effective and rapid identification of bioactive metabolites in the ethyl acetate extract of mangrove without individual standard application. This is the first report on the HRMS based secondary metabolic profiling of B. cylindrica, with comprehensive map of its biologically important metabolites.

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Omelchun, Y., et A. Kobish. « Modern methods for the determination of pesticide residues in beekeeping products and for the diagnostics of bee poisoning ». Naukovij vìsnik veterinarnoï medicini, n^o 2(176) (27 décembre 2022) : 101–10. http://dx.doi.org/10.33245/2310-4902-2022-176-2-101-110.

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Intensification of agricultural production is associated with the use of a significant amount of pesticides, which negatively affects the environment and human health, and food products, including beekeeping products, accordingly require mandatory control of residual amounts of pesticides. This article provides a comparative analysis of the available chromatographic methods for pesticide residue research. The necessity of using modern chromatographic methods to determine residual amounts of pesticides in samples of dead bees and beekeeping products is well-founded. Chromatographic methods of studying these indicators in different types of matrices are a priority. They are effective methods of analysis, widely used due to their versatility - they allow the analysis of complex inorganic and organic compounds in various aggregate states. But one of the most common modern methods for pesticide determination is gas and liquid three-quadrupole tandem chromatography-mass spectrometry (GC and/or LC-MS/MS). The GC-MS/MS method provides quantitative determination of analytes at a level that is an order of magnitude higher than, for example, the gas single quadrupole mass spectrometry method. Modern methods of gas and liquid chromatography in combination with quadrupoletime-of-flight mass spectrometric detection (LC/Q-TOF/MS or GC/ Q-TOF/MS) also allow qualitative and quantitative multicomponent analysis of pesticides in beekeeping products. GC and LC systems combined with high-resolution Orbitrap MS (GC-HRMS(Q-Orbitrap)/LC-HRMS (Q-Orbitrap)) have higher sensitivity, enabling ultra-trace detection, and are the most sensitive screening method for multicomponent determination of pesticide residues. Thus, the latest chromatographic methods are able to meet the needs of analytical testing and research laboratories in the field of food safety, including beekeeping products. Key words: chromatographic methods, thin-layer chromatography, gas chromatography, liquid chromatography, mass spectrometry, multi-component analysis, pesticides, honey, dead bees.

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Miralles, Pablo, Vicent Yusà, Yovana Sanchís et Clara Coscollà. « Determination of 60 Migrant Substances in Plastic Food Contact Materials by Vortex-Assisted Liquid-Liquid Extraction and GC-Q-Orbitrap HRMS ». Molecules 26, n^o 24 (16 décembre 2021) : 7640. http://dx.doi.org/10.3390/molecules26247640.

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A GC-HRMS analytical method for the determination of 60 migrant substances, including aldehydes, ketones, phthalates and other plasticizers, phenol derivatives, acrylates, and methacrylates, in plastic food contact materials (FCM) has been developed and validated. The proposed method includes migration tests, according to Commission Regulation (EU) 10/2011, using four food simulants (A, B, C, and D1), followed by vortex-assisted liquid–liquid extraction (VA-LLE) and GC-Q-Orbitrap HRMS analysis in selected ion monitoring (SIM) mode, with a resolving power of 30,000 FWHM and a mass accuracy ≤5 ppm. The method was validated, showing satisfactory linearity (R2 ≥ 0.98 from 40 to 400 µg L−1), limits of quantification (40 µg L−1), precision (RSD, 0.6–12.6%), and relative recovery (81–120%). The proposed method was applied to the analysis of field samples, including an epoxy-coated tin food can, a drinking bottle made of Tritan copolyester, a disposable glass made of polycarbonate, and a baby feeding bottle made of polypropylene, showing that they were in compliance with the current European regulation regarding the studied substances.

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Miralles, Pablo, Vicent Yusà, Adriana Pineda et Clara Coscollà. « A Fast and Automated Strategy for the Identification and Risk Assessment of Unknown Substances (IAS/NIAS) in Plastic Food Contact Materials by GC-Q-Orbitrap HRMS : Recycled LDPE as a Proof-of-Concept ». Toxics 9, n^o 11 (1 novembre 2021) : 283. http://dx.doi.org/10.3390/toxics9110283.

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A fast and automated approach has been developed for the tentative identification and risk assessment of unknown substances in plastic food contact materials (FCM) by GC-Q-Orbitrap HRMS. The proposed approach combines GC-HRMS full scan data acquisition coupled to Compound Discoverer™ 3.2 software for automated data processing and compound identification. To perform the tentative identification of the detected features, a restrictive set of identification criteria was used, including matching with the NIST Mass Spectral Library, exact mass of annotated fragments, and retention index calculation. After the tentative identification, a risk assessment of the identified substances was performed by using the threshold of toxicological concern (TTC) approach. This strategy has been applied to recycled low-density polyethylene (LDPE), which could be used as FCM, as a proof-of-concept demonstration. In the analyzed sample, 374 features were detected, of which 83 were tentatively identified after examination of the identification criteria. Most of these were additives, such as plasticizers, used in a wide variety of plastic applications, oligomers of LDPE, and substances with chemical, industrial, or cosmetic applications. The risk assessment was performed and, according to the TTC approach, the obtained results showed that there was no risk associated with the release of the identified substances. However, complementary studies related to the toxicity of the unidentified substances and the potential mixture toxicity (cocktail effects) should be conducted in parallel using bioassays.

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TANIYASU, Sachi, Eriko YAMAZAKI, Nobuyasu HANARI, Itsuki YAMAMOTO et Nobuyoshi YAMASHITA. « Development of GC-Orbitrap-HRMS Method for Volatile Per- and Polyfluoroalkyl Substances in Ambient Air in Japan and China ». BUNSEKI KAGAKU 72, n^o 7.8 (5 juillet 2023) : 307–16. http://dx.doi.org/10.2116/bunsekikagaku.72.307.

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Stashenko, Elena, Andrés Fernando González, Jairo René Martínez, Diego Camilo Durán, Cristhian Andrés Oliveros, Leydé Katerine Gualteros, William Salgar-Rangel, Juan Camilo Henríquez et Juan Diego Rojas. « Hallazgo de diclofenaco en un producto fitoterapéutico a base de caléndula comercializado en Colombia ». Revista de la Universidad Industrial de Santander. Salud 52, n^o 3 (31 août 2020) : 261–84. http://dx.doi.org/10.18273/revsal.v52n3-2020008.

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Introducción: la consulta de un particular que trajo un producto fitoterapéutico a base de caléndula cuyo consumo le causó fuertes reacciones adversas, originó esta investigación sobre la composición de este producto. Objetivo: caracterizar la composición química de muestras de lotes diferentes de un producto comercial denominado fitoterapéutico a base de caléndula (Calendula officinalis) (PFC) comercializado en Colombia. Metodología: se analizaron tabletas de ocho cajas del PFC de cuatro lotes diferentes de producción (2017 y 2018). Se llevó a cabo el análisis de espacio de cabeza (HS) de tabletas por microextracción en fase sólida (SPME), con una fibra PDMS/DVB (65 μm), expuesta al HS de la muestra durante 30 min a 50 °C. Las fracciones volátiles se analizaron por cromatografía de gases acoplada a espectrometría de masas (GC/MS). Los extractos de tabletas obtenidos con mezcla de metanol:agua (1:1, v/v) se analizaron por cromatografía líquida (LC) de alta (HPLC) y ultra-alta eficiencia (UHPLC), con detectores de arreglo de diodos (DAD) y espectrometría de masas de alta resolución (HRMS), respectivamente; la cuantificación de diclofenaco se hizo por calibración con patrón externo y poradición de estándar. Los espectros de masas de baja y alta resolución y patrones de fragmentación de las sustancias detectadas se estudiaron, usando GC/HRMS y LC/HRMS-Orbitrap. Resultados: en tabletas analizadas por HS-SPME, se encontraron monoterpenoides y sesquiterpenoides de origen vegetal, ftalatos, residuos de solventes (2-cloroetanol, etilenglicol) y sustancias químicas intermediarias en la síntesis de diclofenaco (2,6-dicloroanilina y 2,6-cloro-N-fenil-bencenamina). En los cromatogramas, obtenidos por GC/MS de los extractos de tabletas obtenidos con diclorometano, se detectaron diclofenaco, sus impurezas A, B y C, los ésteres de diclofenaco y algunas otras impurezas. Diclofenaco en cantidad ca. 40 mg (7-8%) se cuantificó por HPLC en tabletas (> 70 analizadas) escogidas al azar de ocho cajas del PFC, adquirido en el mercado local de Bucaramanga (Colombia). Conclusión: en cada tableta analizada se determinaron alrededor de 40 mg del compuesto sintético diclofenaco (sustancia no declarada en la etiqueta del producto) y en ninguna se detectaron ésteres de los triterpenoides oleanano o faradiol, constituyentes del extracto de caléndula que poseen actividad antiinflamatoria; se encontraron algunos flavonoides comunes a muchas plantas, en cantidades mil veces menores que la de diclofenaco.

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Belarbi, Saida, Martin Vivier, Wafa Zaghouani, Aude De Sloovere, Valérie Agasse-Peulon et Pascal Cardinael. « Comparison of new approach of GC-HRMS (Q-Orbitrap) to GC–MS/MS (triple-quadrupole) in analyzing the pesticide residues and contaminants in complex food matrices ». Food Chemistry 359 (octobre 2021) : 129932. http://dx.doi.org/10.1016/j.foodchem.2021.129932.

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Nunes, Vanessa O., Raquel V. S. Silva, Gilberto A. Romeiro et Débora A. Azevedo. « The speciation of the organic compounds of slow pyrolysis bio-oils from Brazilian tropical seed cake fruits using high-resolution techniques : GC × GC-TOFMS and ESI(±)-Orbitrap HRMS ». Microchemical Journal 153 (mars 2020) : 104514. http://dx.doi.org/10.1016/j.microc.2019.104514.

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Faleva, Anna V., Ilya I. Pikovskoi, Sergey A. Pokryshkin, Dmitry G. Chukhchin et Dmitry S. Kosyakov. « Features of the Chemical Composition and Structure of Birch Phloem Dioxane Lignin : A Comprehensive Study ». Polymers 14, n^o 5 (28 février 2022) : 964. http://dx.doi.org/10.3390/polym14050964.

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Understanding the chemical structure of lignin in the plant phloem contributes to the systematics of lignins of various biological origins, as well as the development of plant biomass valorization. In this study, the structure of the lignin from birch phloem has been characterized using the combination of three analytical techniques, including 2D NMR, Py-GC/MS, and APPI-Orbitrap-HRMS. Due to the specifics of the phloem chemical composition, two lignin preparations were analyzed: a sample obtained as dioxane lignin (DL) by the Pepper’s method and DL obtained after preliminary alkaline hydrolysis of the phloem. The obtained results demonstrated that birch phloem lignin possesses a guaiacyl–syringyl (G-S) nature with a unit ratio of (S/G) 0.7–0.9 and a higher degree of condensation compared to xylem lignin. It was indicated that its macromolecules are constructed from β-aryl ethers followed by phenylcoumaran and resinol structures as well as terminal groups in the form of cinnamic aldehyde and dihydroconiferyl alcohol. The presence of fatty acids and flavonoids removed during alkaline treatment was established. Tandem mass spectrometry made it possible to demonstrate that the polyphenolic components are impurities and are not incorporated into the structure of lignin macromolecules. An important component of phloem lignin is lignin–carbohydrate complexes incorporating xylopyranose moieties.

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Yfanti, Paraskevi, Polyxeni Lazaridou, Vasiliki Boti, Dimitra Douma et Marilena E. Lekka. « Enrichment of Olive Oils with Natural Bioactive Compounds from Aromatic and Medicinal Herbs : Phytochemical Analysis and Antioxidant Potential ». Molecules 29, n^o 5 (4 mars 2024) : 1141. http://dx.doi.org/10.3390/molecules29051141.

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Olive oil and herbs, two key components of the Mediterranean diet, are known for their beneficial effects on humans. In our study, we incorporated aromatic and medicinal herbs into local monovarietal olive oils via maceration procedures for enrichment. We identified the herbal-derived ingredients that migrate to olive oils and contribute positively to their total phenolic content and functional properties, such as radical scavenging activity. Thus, we characterized the essential oil composition of the aromatic herbs (GC-MS), and we determined the phenolic content and antioxidant capacity of the additives and the virgin olive oils before and after enrichment. The herbal phenolic compounds were analyzed by LC-LTQ/Orbitrap HRMS. We found that olive oils infused with Origanum vulgare ssp. hirtum, Rosmarinus officinalis and Salvia triloba obtained an increased phenolic content, by approximately 1.3 to 3.4 times, in comparison with the untreated ones. Infusion with S. triloba led to a significantly higher antioxidant capacity. Rosmarinic acid, as well as phenolic glucosides, identified in the aromatic herbs, were not incorporated into olive oils due to their high polarity. In contrast, phenolic aglycones and diterpenes from R. officinalis and S. triloba migrated to the enriched olive oils, leading to a significant increase in their phenolic content and to an improvement in their free radical scavenging capacity.

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Thèses sur le sujet "GC-HRMS Orbitrap"

Meziani, Amel. « Développement de méthodes d'extraction et de quantification de résidus de polluants et substances émergentes substances dans les eaux naturelles résiduaires par GCxμGC et GCxGC/HRMS ». Electronic Thesis or Diss., Normandie, 2023. http://www.theses.fr/2023NORMR036.

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La pollution des eaux est une problématique majeure qui affecte tant les écosystèmes aquatiques que sur la santé humaine. Par conséquent, la prévention et la surveillance des pollutions constituent donc un enjeu prioritaire afin d’éviter la dissémination de ces polluants. Dans ce contexte, il est essentiel de recourir à la miniaturisation des systèmes et à des méthodes analytiques afin de surveiller en temps réel l'évolution de la pollution sur le terrain. Dans le cadre de ces travaux de thèse, tout d’abord, la préparation et l’évaluation de µ-colonnes de types multicanaux en GC a été réalisée. Des dépôts avec différentes phases stationnaires ont été effectués et des tests en GC unidimensionnel puis un système bidimensionnel « GC×µGC » avec un modulateur microfluidique ont été réalisés avec succès. Par la suite, une méthode d’extraction par sorption sur barreau magnétique (SBSE) suivi d’une thermo-désorption (TD) et d’une analyse non ciblée par spectrométrie de masse à haute résolution (HRMS) a été développée. Afin de pallier les contraintes de la SBSE classique, de nouvelles phases ont été déposées sur les barreaux magnétiques visant ainsi à améliorer les rendements d’extraction des composés les plus polaires. Enfin, des extractions SBSE des polluants ont été effectuées sur des eaux naturelles provenant d’Algérie et de France suivies d’analyses non ciblées par TD-GC-HRMS OrbitrapTM. Des informations sur la qualité des eaux de surfaces en Algérie mais aussi en France quant au niveau de leur contamination ont pu être données et les différents polluants identifiés ont été ensuite classés selon des niveaux confiances basés sur une échelle d’identification récentes
Water pollution is a major problem that affects both aquatic ecosystems and human health. Therefore, the prevention and the control of the dissemination of contaminants in the environment has become a priority. To achieve that, the use of miniaturized analytical systems to control pollution in real-time on-site appears necessary. The evaluation of µ-columns with radially elongated pillars was performed using different stationary phases. Then the performances of the prepared µ-columns were evaluated on conventional GC and in a comprehensive two-dimensional system « GC×µGC » with a microfluidic modulator as a second columns. Afterwards, a stir bar sportive extraction (SBSE) method and a non-targeted analysis one using GC coupled to a high-resolution mass spectrometry (HRMS) were developed. In order to overcome the limitations of SBSE and improve the extraction yields, new SBSE phases were used for the coating of the stir bar. Finally, SBSE extractions of contaminants were performed on naturel waters collected from Algeria and France followed by a non-target analysis using TD-GC-HRMS OrbitrapTM. Information on the quality of surface waters and the level of pollution were collected for both countries and the annotation of the identified compounds were then classified according to levels of confidence

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Chapitres de livres sur le sujet "GC-HRMS Orbitrap"

Schächtele, Alexander, Björn Hardebusch, Kerstin Krätschmer, Karin Tschiggfrei, Theresa Zwickel et Rainer Malisch. « Analysis and Quality Control of WHO- and UNEP-Coordinated Human Milk Studies 2000–2019 : Polybrominated Diphenyl Ethers, Hexabromocyclododecanes, Chlorinated Paraffins and Polychlorinated Naphthalenes ». Dans Persistent Organic Pollutants in Human Milk, 145–83. Cham : Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-34087-1_6.

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AbstractFour different analytical methods were used for the determination of (1) polybrominated diphenyl ethers (PBDE), (2) hexabromocyclododecanes (HBCDD), (3) chlorinated paraffins (CP) and (4) polychlorinated naphthalenes (PCN) in human milk samples of the WHO/UNEP-coordinated exposure studies. As a laboratory accredited according to EN ISO/IEC 17025, a comprehensive quality control program was applied to assure the reliability of results. This included procedural blanks, the use of numerous quality control samples as in-house reference materials and the participation in proficiency tests (PTs). Trueness was estimated from the PT samples using the assigned values.The mean absolute deviation of the sum parameters ∑PBDE6 and ∑PBDE7 from the assigned values of 53 PT samples analysed between 2006 and 2021 was 12% and 14%, respectively.For α-HBCDD as the most abundant diastereomer and the sum of α-, β- and γ-HBCDD, deviations of the reported value from the assigned value of the proficiency tests (31 samples, analysed between 2007 and 2021) were in most cases below 40% over a large concentration range, e.g., for α-HBCDD, between 0.0084 and 19 ng/g fw. For concentrations above 0.5 ng/g lipid, the deviation was in the range of approximately 0–30%.For short-chain and medium-chain CP (SCCP and MCCP) all z-scores achieved in interlaboratory comparisons during 2017–2020 were within ±2 z and therefore satisfactory (13 PT samples were analysed for ΣCP, ΣSCCP and ΣMCCP using the GC-ECNI-Orbitrap-HRMS method, eight results achieved for ΣCP using the GC-EI-MS/MS method).Due to the lack of available proficiency tests for PCN at the time of measuring the human milk samples of the 2016–2019 period, an external validation for control of the trueness was performed through an interlaboratory comparison with an independent laboratory. The deviation of the ΣPCN13 in five test samples between the external laboratory and CVUA Freiburg was in the range from 3 to 20%. At a later stage (in 2021), the laboratory participated successfully in the first interlaboratory comparison study on PCN congeners in cod liver oil. The z-scores for seven congeners and two sum parameters were within ±2 z and therefore satisfactory. Also, the results for other of the altogether 26 PCN congeners were in accordance with the median values reported by all participants.As a result, the determination of PBDE, HBCDD, CP and PCN in human milk samples of the WHO/UNEP-coordinated exposure studies followed the strict rules of the accreditation system and the general criteria for the operation of testing laboratories as laid down in EN ISO/IEC 17025.

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