المؤلفون: Estévez-Danta, Andrea, Ayala-Cabrera, Juan F., López-Vázquez, Javier, Musatadi, Mikel, Montes, Rosa, Etxebarria, Nestor, Quintana, José Benito, Olivares, Maitane, Prieto, Ailette, Rodil, Rosario, Miró, Manuel, Zuloaga, Olatz

المساهمون: Basque Government, Government of Galicia, Government of Spain Ministry of Universities, Spain Ministry of Science Innovation and Universities

المصدر: TrAC Trends in Analytical Chemistry ; volume 173, page 117653 ; ISSN 0165-9936

مصطلحات موضوعية: Spectroscopy, Analytical Chemistry

الإتاحة: https://doi.org/10.1016/j.trac.2024.117653Test
https://api.elsevier.com/content/article/PII:S0165993624001353?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S0165993624001353?httpAccept=text/plainTest

المؤلفون: Ayala-Cabrera, Juan F., Montero, Lidia, Sahlabji, Taher, Schmitz, Oliver J.

المساهمون: Universität Duisburg-Essen

المصدر: Analytical and Bioanalytical Chemistry ; volume 415, issue 13, page 2561-2573 ; ISSN 1618-2642 1618-2650

مصطلحات موضوعية: Biochemistry, Analytical Chemistry

الوصف: The analysis of complex samples is a big analytical challenge due to the vast number of compounds present in these samples as well as the influence matrix components could cause in the methodology. In this way, comprehensive two-dimensional gas chromatography coupled to mass spectrometry (GC × GC–MS) is a very powerful tool to achieve the characterization of complex samples. Nevertheless, due to possible coelutions occurring in these matrices, mixed spectra are generally obtained with electron ionization (EI) which could extremely complicate the identification of the analytes. Thereby, new methodology setups are required to improve the confidence on the identification in non-targeted determinations. Here, we present a high-throughput methodology consisting of GC × GC with flow modulation coupled to high-resolution atmospheric pressure mass spectrometry (HRMS) via a novel tube plasma ion source (TPI). The flow modulator allows to easily automate the GC × GC method compared to traditional cryo-modulators, while the soft ionization provided by TPI helps to preserve the [M] +• or [M+H] + ions, thus increasing the confidence in the identification. Additionally, the combination of a flow modulation with an atmospheric pressure mass spectrometer significantly improves the sensitivity over flow modulated GC × GC-EI-MS methods because no split is required. This methodology was applied to the analysis of a complex sample such as vermouth where the volatile profile is usually considered by consumers as a product quality indicator since it raises the first sensations produced during its consumption. Using this approach, different classes of compounds were tentatively identified in the sample, including monoterpenes, terpenoids, sesquiterpenoids and carboxylic acid, and carboxylate esters among others, showing the great potential of a GC × GC-TPI-qTOF-MS platform for improving the confidence of the identifications in non-targeted applications.

الإتاحة: https://doi.org/10.1007/s00216-023-04688-6Test

المؤلفون: Ayala-Cabrera, Juan F., Montero, Lidia, Meckelmann, Sven W., Uteschil, Florian, Schmitz, Oliver J.

المصدر: Analytica Chimica Acta ; volume 1238, page 340353 ; ISSN 0003-2670

مصطلحات موضوعية: Spectroscopy, Environmental Chemistry, Biochemistry, Analytical Chemistry

الإتاحة: https://doi.org/10.1016/j.aca.2022.340353Test
https://api.elsevier.com/content/article/PII:S0003267022009242?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S0003267022009242?httpAccept=text/plainTest

المؤلفون: Ayala-Cabrera, Juan F., Montero, Lidia, Meckelmann, Sven W., Uteschil, Florian, Schmitz, Oliver J.

المصدر: Analytica Chimica Acta ; volume 1238, page 340379 ; ISSN 0003-2670

مصطلحات موضوعية: Spectroscopy, Environmental Chemistry, Biochemistry, Analytical Chemistry

الإتاحة: https://doi.org/10.1016/j.aca.2022.340379Test
https://api.elsevier.com/content/article/PII:S0003267022009503?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S0003267022009503?httpAccept=text/plainTest

المؤلفون: Görs, Paul E., Wittenhofer, Pia, Ayala-Cabrera, Juan F., Meckelmann, Sven W.

المساهمون: Volkswagen Foundation, Universität Duisburg-Essen

المصدر: Analytical and Bioanalytical Chemistry ; volume 414, issue 22, page 6621-6634 ; ISSN 1618-2642 1618-2650

مصطلحات موضوعية: Biochemistry, Analytical Chemistry

الوصف: Because of the central role of fatty acids in biological systems, their accurate quantification is still important. However, the impact of the complex matrix of biologically and clinically relevant samples such as plasma, serum, or cells makes the analysis still challenging, especially, when free non-esterified fatty acids have to be quantified. Here we developed and characterized a novel GC–MS method using pentafluorobenzyl bromide as a derivatization agent and compared different ionization techniques such as atmospheric pressure chemical ionization (APCI), atmospheric pressure chemical photoionization (APPI), and negative ion chemical ionization (NICI). The GC-APCI-MS showed the lowest limits of detection from 30 to 300 nM for a broad range of fatty acids and a similar response for various fatty acids from a chain length of 10 to 20 carbon atoms. This allows the number of internal standards necessary for accurate quantification to be reduced. Moreover, the use of pentafluorobenzyl bromide allows the direct derivatization of free fatty acids making them accessible for GC–MS analysis without labor-intense sample pretreatment.

الإتاحة: https://doi.org/10.1007/s00216-022-04223-zTest

المؤلفون: Montero, Lidia, Meckelmann, Sven W., Kim, Hyerin, Ayala-Cabrera, Juan F., Schmitz, Oliver J.

المساهمون: Universität Duisburg-Essen

المصدر: Analytical and Bioanalytical Chemistry ; volume 414, issue 18, page 5445-5459 ; ISSN 1618-2642 1618-2650

مصطلحات موضوعية: Biochemistry, Analytical Chemistry

الوصف: Cannabis is an ancient plant that has been used for therapeutic and recreational purposes. Nowadays, industrial hemp, a variety with low concentration of the psychoactive cannabinoid Δ 9 -tetrahydrocannabinol (THC) and high concentration of non-psychoactive cannabinoids, is getting more and more interest in the food, pharmaceutical, and cosmetic industry. However, cannabis not only contains cannabinoids as bioactive components but also other metabolites like terpenes and phenolic compounds, and the content of these interesting secondary metabolites greatly differs with the genetic variety of the plant. Due to the huge complexity of composition of the cannabis matrix, in this work, a comprehensive two-dimensional liquid chromatography (LC × LC) method has been developed as a very power separation technique coupling a pentafluorophenyl (PFP) and a C18 in the first and second dimensions. Two industrial hemp strains (cookie and gelato) were analyzed to determine the difference in their content of cannabinoids and phenolic compounds. To do this, a new demodulation process was applied for the first time to transform 2D raw data into 1D data which allowed carrying out the chemometric analysis needed to determine the statistical differences between the hemp strains. The cookie strain presented a total of 41 cannabinoid markers, while the gelato strain presented more representative phenolic compounds, in total 24 phenolic compounds were detected as potential markers of this sample. These differences in the chemical composition could determine the industrial destiny of the different hemp strains. Graphical abstract

الإتاحة: https://doi.org/10.1007/s00216-022-03925-8Test

المؤلفون: Görs, Paul E.¹ (AUTHOR), Ayala-Cabrera, Juan F.^1,2,3 (AUTHOR), Meckelmann, Sven W.¹ (AUTHOR) sven.meckelmann@uni-due.de

المصدر: Journal of the American Society for Mass Spectrometry. 11/1/2023, Vol. 34 Issue 11, p2538-2546. 9p.

مستخلص: The position of double bonds in unsaturated fatty acids is strongly connected to their biological effects, but their analytical characterization is still challenging. However, the ionization of unsaturated fatty acids by a GC-APCI leads to regiospecific in-source fragment ions, which can be used to identify the double bond position. The fragment ions are oxidized species that occur mostly at the double bond closest to the carboxylic acid group. This effect can be further promoted by using benzaldehyde as a gas-phase reactant. This allows the identification of the Δ-notation of the fatty acid, and based on additional information such as m/z and retention time, it is possible to annotate the corresponding fatty acid. The developed method also enables the quantification of fatty acids in one step with high selectivity and sensitivity. Moreover, rare fatty acids can be identified in suspected target approaches that are often not available as standards. This was demonstrated by analyzing fish oil samples that provide a complex mixture of highly unsaturated fatty acids and by identifying rare fatty acids such as hexadecatetraenoic acid (FA 16:4 Δ6). [ABSTRACT FROM AUTHOR]

المؤلفون: Ayala-Cabrera, Juan F, Lacorte Bruguera, Silvia, Moyano, Encarnación, Santos, Francisco Javier

المساهمون: Ministerio de Ciencia, Innovación y Universidades (España), orcid

مصطلحات موضوعية: Spanish Natural Parks, Atmospheric pressure photoionization, Dechlorane Plus, Gas chromatography-high-resolution mass spectrometry, Gull eggs

الوصف: Here, a new gas chromatography-atmospheric pressure photoionization-high-resolution mass spectrometry (GC-APPI-HRMS) method combined with selective pressurized liquid extraction (sPLE) has been developed for the selective determination of Dechlorane Plus (DP) and its related compounds in gull egg samples used as a bioindicator of contamination. To the best of our knowledge, this is the first time these compounds have been analyzed by GC-MS using atmospheric pressure photoionization (APPI). Negative ion dopant-assisted APPI using vapors of diethyl ether and a source temperature of 250 °C provided high ionization efficiencies and mass spectra characterized by intense in-source fragment ions as well as the presence of molecular ion and characteristic cluster ions containing oxygen atoms in their chemical structure. This made it possible to improve the selectivity in the determination of these compounds compared to that obtained with traditional GC-MS ion sources. Under optimized conditions, the sPLE GC-APPI-HRMS (Orbitrap) method provided high recoveries (> 91%), good precisions (RSD% < 12%), and low method limits of detection (0.1-3.5 pg g-1 wet weight). The developed methodology has been applied to the determination of DP and related compounds in eggs of two gull species (L. michahellis and L. audouinii) from several Spanish protected areas. The results obtained showed significant differences in the DP concentration profiles in eggs from different gull breeding locations and between gull species of the same protected area. These results demonstrated the good performance of the GC-APPI-HRMS system to achieve a selective and sensitive determination of DP and related compounds in complex environmental samples. ; This work received financial support from the Spanish Ministry of Science, Innovation and Universities under the project PGC2018-095013-B-I00 and PID2019-105732GB-C21, as well as the Generalitat of Catalonia under the project 2017-SGR-310 and the Spanish Autonomous Organism of National Parks under the ...

العلاقة: #PLACEHOLDER_PARENT_METADATA_VALUE#; info:eu-repo/grantAgreement/EC/MICIU/PID2019-105732GB-C21; info:eu-repo/grantAgreement/EC/MICIU/PGC2018-095013-B-I00; Analytical and bioanalytical chemistry; Postprint; Sí; Analytical and Bioanalytical Chemistry 413: 3421–3431 (2021); http://hdl.handle.net/10261/264479Test; 2-s2.0-85102904415; https://api.elsevier.com/content/abstract/scopus_id/85102904415Test

الإتاحة: https://doi.org/10.1007/s00216-021-03286-8Test
http://hdl.handle.net/10261/264479Test
https://api.elsevier.com/content/abstract/scopus_id/85102904415Test

المؤلفون: Ayala-Cabrera, Juan F., Santos, F. Javier, Moyano, Encarnación

المساهمون: AGAUR, Gobierno de Espana Ministerio de Educacion Cultura y Deporte, Gobierno de Espana Ministerio de Ciencia Innovacion y Universidades

المصدر: Trends in Environmental Analytical Chemistry ; volume 30, page e00122 ; ISSN 2214-1588

مصطلحات موضوعية: Environmental Chemistry, Analytical Chemistry

الإتاحة: https://doi.org/10.1016/j.teac.2021.e00122Test
https://api.elsevier.com/content/article/PII:S221415882100009X?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S221415882100009X?httpAccept=text/plainTest

المؤلفون: Montero, Lidia, Arrizabalaga-Larrañaga, Ane, Ayala-Cabrera, Juan F.

المصدر: Emerging Food Authentication Methodologies Using GC/MS ; page 215-251 ; ISBN 9783031302879 9783031302886

الإتاحة: https://doi.org/10.1007/978-3-031-30288-6_8Test