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Structural characterization of novel chemotactic and mastoparan peptides from the venom of the social wasp Agelaia pallipes pallipes by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry

Mendes, Maria Anita; De Souza, Bibiana Monson; Dos Santos, Lucilene Delazari; Palma, Mario Sergio
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 636-642
ENG
Relevância na Pesquisa
96.25%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); High-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS) and high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) techniques were applied for the detection, purification, monitoring, and sequencing of two novel and biologically active peptides occurring at very low levels in the venom of the wasp Agelaia pallipes pallipes. These peptides were sequenced under LC/ESI-MS/MS conditions and designated as Agelaia-CP (I/L-L-G-T-I-L-G-L-L-K-G-I/L-NH2, MW 1207.8Da) and Agelaia-MP (I/L-N-W-L-K-L-G-K-A-I-I-D-A-I/L-NH2, MW 1565.0Da). The peptide Agelaia-CP showed no hemolytic activity, but it behaved as a mast cell degranulator and induced a potent chemotaxis in polymorphonucleated leukocyte (PMNL) cells, typical of a wasp chemotactic peptide. The peptide Agelaia-MP showed both powerful mast cell degranulation and hemolysis of washed rat red blood cells, and is thus assigned as a new member of the mastoparan family of peptides. Both peptides seem to be directly involved in the strong inflammatory reactions associated with wasp stings. © Copyright 2004 John Wiley & Sons, Ltd.

Characterization of proanthocyanidins from Parkia biglobosa (Jacq.) G. Don. (Fabaceae) by flow injection analysis - Electrospray ionization ion trap tandem mass spectrometry and liquid chromatography/electrospray ionization mass spectrometry

Tala, Viviane Raïssa Sipowo; Da Silva, Viviane Candida; Rodrigues, Clenilson Martins; Nkengfack, Augustin Ephrem; Dos Santos, Lourdes Campaner; Vilegas, Wagner
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 2803-2820
ENG
Relevância na Pesquisa
96.27%
The present study investigates the chemical composition of the African plant Parkia biglobosa (Fabaceae) roots and barks by Liquid Chromatography - Electrospray Ionization and Direct Injection Tandem Mass Spectrometry analysis. Mass spectral data indicated that B-type oligomers are present, namely procyanidins and prodelphinidins, with their gallate and glucuronide derivatives, some of them in different isomeric forms. The analysis evidenced the presence of up to 40 proanthocyanidins, some of which are reported for the first time. In this study, the antiradical activity of extracts of roots and barks from Parkia biglobosa was evaluated using DPPH method and they showed satisfactory activities.

Electrospray tandem mass spectrometry of 2H-chromenes

Campos, Ana M. F. Oliveira; Domingues, M. R. M.; Domingues, Pedro; Oliveira, M. Manuel; Carvalho, Luís H. Melo de; Correia, António J. Ferrer
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
Publicado em //2004 ENG
Relevância na Pesquisa
96.14%
Several 2H-chromenes, derived from carbazoles, were analyzed by electrospray tandem mass spectrometry. The 2H-chromenes constitute an important class of compounds that exhibit photochromic activity. The fragmentation pathways of the protonated molecular species [M+H]+ were studied and main fragmentation pathways of these compounds were identified. Fragmentation pathways of [M+D]+ ions were also studied in order to obtain information about the ionizing proton or deuteron. It was found that proton is not preferentially located on the nitrogen atom. The charge is preferentially located as a tertiary carbocation, resulting from the uptake of the proton (or deuteron) by the zwitterionic open structure of the chromenes. The major fragmentation occurred by cleavage of the gama-bond relative to the carbocation center, leading to a fragment at m/z 191 (C5H11+ or C14H9N+•), which are the most abundant fragment ions for almost all compounds. The presence of substituents in the chromene ring does not change this behavior. Other observed common fragmentation pathways included loss of CH3 (15 Da), loss of CO (28 Da), combined loss of CO and CH3 (43 Da), and loss of phenyl ring via combined loss of C6H4 and CH3 (-91Da) and combined loss of C6H6 and CO (-106 Da).

Risk assessment of representative and priority pesticides, in surface water of the Alqueva reservoir (South of Portugal) using on-line solid phase extraction-liquid chromatography-tandem mass spectrometry

Palma, P.; Kuster, M.; Alvarenga, P.; Palma, V. L.; Fernandes, R. M.; Soares, A. M. V. M.; de Aida, M. J. L.; Barcelo, D.; Barbosa, I. R.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
96.14%
Surface waters located in intensive agricultural areas are more vulnerable to the pesticides contamination, which is a major concern if the water is intended to be used for human consumption. The aim of this study was to evaluate the presence and the distribution of pesticides in the Alqueva reservoir, an important source of water supply (South of Portugal), considering their representativeness in the agricultural practice of the area. For the analysis of pesticides risk impact we used the environmental quality standards in the field of water policy proposed recently by the European Commission. The pesticides belonging to the classes of phenylureas, triazines, chloroacetanilides, organophosphorous and thiocarbamates were analysed by on-line solid phase extraction-liquid chromatography-tandem mass spectrometry. The pesticides more frequently detected were atrazine, simazine, diuron and terbuthylazine. The highest levels of these pesticides were registered in spring, after pesticides treatment, namely in olive-tree and vine crops. The priority pesticides atrazine and diuron reached values above the annual average proposed in the European Union Legislation. The herbicide atrazine reached values that surpassed the proposed maximum allowable concentration (2 000 ng L(-1)). The sampling stations most affected by these pesticides were Sra. Ajbda...

Plasma free and total carnitine measured in children by tandem mass spectrometry

Osorio,J.H.; Pourfarzam,M.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2002 EN
Relevância na Pesquisa
96.23%
Free and total carnitine quantification is important as a complementary test for the diagnosis of unusual metabolic diseases, including fatty acid degradation disorders. The present study reports a new method for the quantification of free and total carnitine in dried plasma specimens by isotope dilution electrospray tandem mass spectrometry with sample derivatization. Carnitine is determined by looking for the precursor of ions of m/z = 103 of N-butylester derivative, and the method is validated by comparison with radioenzymatic assay. We obtained an inter- and intra-day assay coefficient of variation of 4.3 and 2.3, respectively. Free and total carnitine was analyzed in 309 dried plasma spot samples from children ranging in age from newborn to 14 years using the new method, which was found to be suitable for calculating reference age-related values for free and total carnitine (less than one month: 19.3 ± 2.4 and 23.5 ± 2.9; one to twelve months: 28.8 ± 10.2 and 35.9 ± 11.4; one to seven years: 30.7 ± 10.3 and 38.1 ± 11.9; seven to 14 years: 33.7 ± 11.6, and 43.1 ± 13.8 µM, respectively). No difference was found between males and females. A significant difference was observed between neonates and the other age groups. We compare our data with reference values in the literature...

Electrospray ionization tandem mass spectrometry of the two main antimalarial drugs: artemether and lumefantrine

Santos,Vanessa G. dos; Alves,Ricardo J.; Eberlin,Marcos N.; Pianetti,Gerson A.; César,Isabela C.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
Relevância na Pesquisa
96.22%
Electrospray ionization in the positive ion mode and high resolution and high accuracy tandem mass spectrometry performed in a hybrid quadrupole time-of-flight mass spectrometer were used to investigate the dissociation chemistry of the intact molecules of two most widely used antimalarial drugs: artemether and lumefantrine. The dissociation pathways of their cationized and protonated forms were rationalized based on high accuracy mass measurements and isotopic distributions. The obtained results should benefit LC-MS/MS monitoring and quantitation by mass spectrometry of the artemether and lumefantrine molecules, as well as of new derivatives or other structurally related antimalarial drugs.

Method Development for the Analysis of Smokeless Powders and Organic Gunshot Residue by Ultra Performance Liquid Chromatography with Tandem Mass Spectrometry

Thomas, Jennifer L.
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Relevância na Pesquisa
96.14%
The goal of this project was to develop a rapid separation and detection method for analyzing organic compounds in smokeless powders and then test its applicability on gunshot residue (GSR) samples. In this project, a total of 20 common smokeless powder additives and their decomposition products were separated by ultra performance liquid chromatography (UPLC) and confirmed by tandem mass spectrometry (MS/MS) using multiple reaction monitoring mode (MRM). Some of the targeted compounds included diphenylamines, centralites, nitrotoluenes, nitroglycerin, and various phthalates. The compounds were ionized in the MS source using simultaneous positive and negative electrospray ionization (ESI) with negative atmospheric pressure chemical ionization (APCI) in order to detect all compounds in a single analysis. The developed UPLC/MS/MS method was applied to commercially available smokeless powders and gunshot residue samples recovered from the hands of shooters, spent cartridges, and smokeless powder retrieved from unfired cartridges. Distinct compositions were identified for smokeless powders from different manufacturers and from separate manufacturing lots. The procedure also produced specific chemical profiles when tested on gunshot residues from different manufacturers. Overall...

Screening for potential pigments derived from anthocyanins in red wine using nanoelectrospray tandem mass spectrometry

Hayasaka, Y.; Asenstorfer, R.
Fonte: Amer Chemical Soc Publicador: Amer Chemical Soc
Tipo: Artigo de Revista Científica
Publicado em //2002 EN
Relevância na Pesquisa
96.14%
Red wine extracts were screened for potential wine pigments derived from anthocyanins, using a combination of nanoelectrospray tandem mass spectrometry techniques. Fourteen aglycons were considered to be of anthocyanidin origin on the basis of their MS/MS spectra. The proposed structures of the aglycons were anthocyanidin C-4 substituted with vinyl linkage between C-4 and the hydroxy group at C-5. The anthocyanidin derivatives identified in the wine extracts were vinyl, vinylmethyl, vinylformic acid, 4-vinylphenol, 4-vinylguaiacol, and vinylcatechin adducts of malvidin as well as vinylformic acid and 4-vinylphenol adducts of peonidin and petunidin. The presence of vinyl alcohol, 4-vinylcatechol, and 4-vinylsyringol adducts of malvidin was also proposed.; © 2002 American Chemical Society

Assessment of androgen concentration in women: liquid chromatography-tandem mass spectrometry and extraction RIA show comparable results

Janse, F.; Eijkemans, M.; Goverde, A.; Lentjes, E.; Hoek, A.; Lambalk, C.; Hickey, T.; Fauser, B.; Norman, R.
Fonte: Bio Scientifica Ltd Publicador: Bio Scientifica Ltd
Tipo: Artigo de Revista Científica
Publicado em //2011 EN
Relevância na Pesquisa
96.14%
Objective: The measurement of serum testosterone in women is challenging due to lack of trueness, precision, and sensitivity of various available testosterone assays. Accurate assessment of testosterone in women is crucial especially in conditions associated with alleged over- or under-production of testosterone, such as in polycystic ovary syndrome (PCOS) or primary ovarian insufficiency (POI). The aim of this study was to measure and compare androgen concentrations in women with PCOS, POI, and female controls and to evaluate the performance of extraction RIA and liquid chromatography–tandem mass spectrometry (LC–MS/MS) in these women. Design Cross:-sectional study. Methods: Carefully phenotyped women with POI (n=208) or PCOS (n=200) and 45 healthy, regularly cyclic female controls were included. Method comparison analyses were performed for total testosterone, androstenedione (AD), and DHEA, as measured by LC–MS/MS and extraction RIA. Results: All androgen levels were significantly elevated in women with PCOS compared with POI patients (P<0.05) and controls (P<0.05). Women with POI presented with similar androgen concentrations as controls, except for AD. Compared with measurements by extraction RIA, testosterone, DHEA, and AD concentrations measured by LC–MS/MS were systematically lower. However...

Neue Methoden des Therapiemonitorings bei Patienten mit Propionazidämie und Methylmalonazidämie durch die Quantifizierung der Acylcarnitine im Trockenblut mittels Tandemmassenspektrometrie; Referenzwerte bei gesunden Erwachsenen; New methods for monitoring therapy of patients with propionic acidemia and methylmalonic acidemia by quantification of acylcarnitines in dried blood by tandem mass spectrometry; Reference values for healthy adults under different conditions

Klupsch, Birgit
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
Relevância na Pesquisa
96.25%
Neue Methoden des Therapiemonitorings bei Patienten mit Propionazidämie und Methylmalonazidämie durch die Quantifizierung der Acylcarnitine im Trockenblut mittels Tandemmassenspektrometrie Referenzwerte bei gesunden Erwachsenen unter verschiedenen Bedingungen Die diätetische Behandlung und die Gabe von Carnitin hat zu einer großen Verbesserung der Lebenserwartung von Patienten mit Propionazidämie (PPA) und Methylmalonazidämie (MMA) geführt, doch ist die psychomotorische Entwicklung weiterhin unbefriedigend. Bis-lang gibt es für diese Erkrankungen noch keine einfach durchführbare Stoffwechselüberwa-chung, die der Therapieoptimierung dient. In der vorliegenden Arbeit wurde bei fünf Patienten mit MMA und neun Patienten mit PPA überprüft, ob die Messung eines Quotienten aus Propionylcarnitin und Palmitoylcarnitin (C3/ C16) in auf Filterpapier aufgetropftem Blut mittels Tandemmassenspektrometrie ein geeigne-ter Parameter für die Überprüfung der diätetischen und medikamentösen Stoffwechsellage darstellt. Hierfür wurde in einem 14-tägigen Abstand eine Blutentnahme von den Eltern durchgeführt sowie der klinische Zustand mittels eines strukturierten Telefoninterviews durch einen klinischen Score evaluiert. Außerdem wurden das freie Carnitin und die Acylcarnitine bei gesunden Probanden unter verschiedenen Bedingungen gemessen und untersucht...

Bestimmung von Referenzwerten für krankheitsrelevante Aminosäurenkonzentrationen im Trockenblut mittels Tandem-Massenspektrometrie in einem Normalkollektiv gesunder Neugeborener; Reference values on screening relevant amino acids in healthy newborns measured by tandem mass spectrometry

Morgenthaler, Janine
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
Relevância na Pesquisa
96.28%
Durch den Einsatz der Tandem-Massenspektrometrie (TMS) im Neugeborenen-Screening ergibt sich die Möglichkeit, das Screening auf metabolische Erkrankungen unter anderem im Bereich des Aminosäurenstoffwechsels zu erweitern. Eine frühzeitige, präsymptomatische Diagnose und Therapie dieser Erkrankungen soll den Behandlungserfolg verbessern und vor allem irreversible Schäden der geistigen Entwicklung und lebensbedrohliche Entgleisungen des Stoffwechsels verhindern. Bislang gibt es noch keine Referenzwerte von quantitativ mittels TMS gemessenen Konzentrationen krankheitsrelevanter Aminosäuren in einem Normalkollektiv gesunder, reifer Neugeborener und deren Abhängigkeit von Alter, Gestationsalter, Geschlecht, Geburtsgewicht, Gewichtsverlust und Ernährung. Die vorliegende Arbeit hatte zum Ziel, die Einflüsse dieser Faktoren auf die Aminosäurenkonzentrationen gesunder Neugeborener zu untersuchen und Referenzwerte für ein gesundes Kollektiv zu erstellen. Weiterhin wurden die Konzentrationen von Phenylalanin (Phe) und Tyrosin (Tyr) und damit des Phe/Tyr-Quotienten in den ersten 48 Lebensstunden von 6 Patienten mit Risiko für Phenylketonurie (PKU) bestimmt, um Aufschluß über den frühest möglichen Zeitpunkt der Diagnosestellung PKU mittels TMS zu gewinnen. Es wurden prospektiv 2159 Neugeborene untersucht...

Der pathologische Phospholipid-Metabolismus der Leber bei Mukoviszidose: Stoffwechseluntersuchungen mittels [Methyl-D9]Cholinchlorid und Tandemmassenspektrometrie; The pathological phospholipid-metabolism of the liver in cystic fibrosis: analysis of metabolism using [methyl-D9]choline chloride and tandem mass spectrometry

Tschürtz, Sandra Miriam
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
Relevância na Pesquisa
96.19%
Hintergrund der vorliegenden Studie ist, dass bei Cystischer Fibrose (CF) die Leberfunktionsstörung nach der Lungen- und Pankreas-Problematik die bedeutendste Rolle spielt, ihre Pathophysiologie jedoch nur inkomplett verstanden ist: Die hohe biliäre Sekretion von Phosphatidylcholin (PC) und sein enterohepatischer Kreislauf bedingen in Kombination mit einer insuffizienten enteralen Spaltung und Rückresorption von PC eine erhöhte Ausscheidung cholinhaltiger Komponenten über die Fäzes. Der resultierende Cholinmangel und die Störung der hepatischen PC-Homöostase könnten dann eine verminderte Lipoproteinsekretion („very low densitiy lipoprotein“, VLDL) durch die Leber zur Folge haben, um den enterohepatischen Kreislauf des Galle-PCs aufrecht zu erhalten. Neben einer gestörten Versorgung der extrahepatischen Gewebe mit Cholin und essentiellen Fettsäuren aus dem PC der VLDL kommt es zu einer Akkumulation von Triglyceriden in der Leber (Lebersteatose). In schweren Fällen, bei denen die Leber nicht genug PC bildet, um die eigene Membranhomöostase aufrecht zu erhalten, kann dies die Ursache von Steatohepatitiden bis hin zum terminalen Leberversagen sein. In der durchgeführten Studie wurde die zuvor an gesunden Probanden etablierte Technik der [Methyl-D9]Cholin-Markierung zusammen mit Tandemmassenspektrometrie verwendet. Diese Markierungstechnik stellt einen „pulse-chase“-Versuch in vivo dar...

Determination of betaines in vegetable oils by capillary electrophoresis tandem mass spectrometry. Application to the detection of olive oil adulteration with seed oils.

Sánchez Hernández, Laura; Castro Puyana, María; Marina Alegre, María Luisa; Crego Navazo, Antonio Luis
Fonte: Wiley-VCH Publicador: Wiley-VCH
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/acceptedVersion Formato: application/pdf
ENG
Relevância na Pesquisa
96.14%
The final publication is available at Springer via http://dx.doi.org/10.1002/elps.201100005; A capillary electrophoresis-tandem mass spectrometry methodology enabling the simultaneous determination of betaines (glycine betaine, trigonelline, proline betaine and total content of carnitines) in vegetable oils was developed. Betaines were derivatized with butanol previous to their baseline separation in 10 min using a 0.1 M formic acid buffer at pH 2.0. Ion trap conditions were optimized in order to maximize selectivity and sensitivity. Analytical characteristics of the proposed method were established by evaluating its selectivity, linearity, precision (RSDs ranged from 4.8% to 10.7% for corrected peak areas), accuracy by means of recovery studies (from 80% to 99%) and LODs and LOQs at 0.1 ppb level. The method was applied to the determination of the selected betaines in seed oils and extra virgin olive oils. MS2 experiments provided the fingerprint fragmentation for all betaines studied in seed oils. In extra virgin olive oils, carnitines were not detected being possible to propose them as a feasible novel marker for the detection of adulterations of olive oils. Application of the developed method to the analysis of different mixtures of extra virgin olive oil with seed oil (between 2-10 %) enabled the detection and quantitation of the total content of carnitines. The results obtained show the high potential of the developed method for the authentication and quality control of olive oils.; Authors thank the Spanish Ministry of Science and Innovation (project CTQ2009- 09022) and the Comunidad Autónoma of Madrid (Spain) and european funding from FEDER programme (project S2009/AGR-1464...

Structural characterization of novel chemotactic and mastoparan peptides from the venom of the social wasp Agelaia pallipes pallipes by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry

Mendes, Maria Anita; Souza, Bibiana Monson de; Santos, Lucilene Delazari dos; Palma, Mario Sergio
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 636-642
ENG
Relevância na Pesquisa
96.25%
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); High-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS) and high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) techniques were applied for the detection, purification, monitoring, and sequencing of two novel and biologically active peptides occurring at very low levels in the venom of the wasp Agelaia pallipes pallipes. These peptides were sequenced under LC/ESI-MS/MS conditions and designated as Agelaia-CP (I/L-L-G-T-I-L-G-L-L-K-G-I/L-NH2, MW 1207.8Da) and Agelaia-MP (I/L-N-W-L-K-L-G-K-A-I-I-D-A-I/L-NH2, MW 1565.0Da). The peptide Agelaia-CP showed no hemolytic activity, but it behaved as a mast cell degranulator and induced a potent chemotaxis in polymorphonucleated leukocyte (PMNL) cells, typical of a wasp chemotactic peptide. The peptide Agelaia-MP showed both powerful mast cell degranulation and hemolysis of washed rat red blood cells, and is thus assigned as a new member of the mastoparan family of peptides. Both peptides seem to be directly involved in the strong inflammatory reactions associated with wasp stings. © Copyright 2004 John Wiley & Sons, Ltd.

Analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in vegetable oil samples by gas chromatography–ion trap tandem mass spectrometry

Malavia, Jessica; Ábalos, Manuela; Santos, F. Javier; Abad Holgado, Esteban; Rivera Aranda, Josep; Galcerán, M. Teresa
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 19968 bytes; application/msword
ENG
Relevância na Pesquisa
96.19%
12 pages, 5 figures.-- PMID: 17399728 [PubMed].-- Printed version published on May 18, 2007.; Gas chromatography coupled to ion trap tandem mass spectrometry (CG–MS–MS) has been evaluated for the analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in vegetable oil samples containing different concentration levels (0.2–6 pg WHO-TEQ g−1 for both PCDD/Fs and dl-PCBs) of the 29 toxic congeners of PCDD/F and dioxin-like PCBs. The effect of potential interfering compounds such as polychlorinated naphthalenes (PCNs), polychlorinated biphenyls (PCBs) and polychlorinated diphenylethers (PCDEs) on the quantification of mono-ortho PCBs has been investigated. In addition, the influence of the clean-up procedure on the final determination by CG–MS–MS was studied, showing that the quality of the results depends to a great extent on this analytical step. Quality parameters have been established and good precisions (CV: 3–19%) and low limits of detection for PCDD/Fs (0.04–0.20 pg g−1 oil) and dl-PCBs (0.08–0.64 pg g−1 oil) were obtained. The method was validated by a comparison of the CG–MS–MS results with those obtained by GC–HRMS.; The authors gratefully acknowledge the Ministerio de Ciencia y Tecnología and FEDER...

Ion-trap tandem mass spectrometry for the analysis of polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like polychlorinated biphenyls in food

Malavia, Jessica; Ábalos, Manuela; Santos, F. Javier; Abad Holgado, Esteban; Rivera Aranda, Josep; Galcerán, M. Teresa
Fonte: American Chemical Society Publicador: American Chemical Society
Tipo: Artículo Formato: 19968 bytes; application/msword
ENG
Relevância na Pesquisa
96.23%
9 pages, 4 tables, 3 figures.-- PMID: 18052095 [PubMed].-- Printed version published on Dec 26, 2007.; This paper reports on the applicability of gas chromatography coupled to ion-trap tandem mass spectrometry (GC/ITMS/MS) for the analysis of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dl-PCBs) in food. MS/MS parameters were selected to achieve the high sensitivity and selectivity required for food analysis. Good precision (RSD = 5–18% for PCDD/Fs and 6–14% for dl-PCBs) and low limits of detection for PCDD/Fs (0.1–0.93 pg/g of fat) and dl-PCBs (0.1–0.89 pg/g of fat) were obtained. A comparative study of the congener-specific determination using both GC/ITMS/MS and GC-high resolution mass spectrometry (GC/HRMS) was performed by analyzing several matrices such as milk, fish oil, chicken, pork, fish, eggs, and a chicken compound feed, at low pg/g levels. The results using GC/ITMS/MS were in good agreement with those obtained by GC/HRMS. Consequently, GC/ITMS/MS is proposed for the analysis of PCDD/Fs and dl-PCBs in food and feed samples.; We gratefully thank the Ministerio de Ciencia y Tecnología under Project CTM2006-00753/TECNO and EU Project DIFFERENCE (G6RD-CT-2001-00623) for financially supporting this study.; Peer reviewed

Liquid chromatography-tandem mass spectrometry for the analysis of pharmaceutical residues in environmental samples: a review

Petrovic, Mira; Hernando, María Dolores; Díaz-Cruz, M. Silvia; Barceló, Damià
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
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96.19%
14 pages, 5 figures.-- PMID: 15844508 [PubMed].-- Printed version published Mar 4, 2005.-- Issue title: "Mass Spectrometry: Innovation and Application. Part IV".; Pharmaceutical residues are environmental contaminants of recent concern and the requirements for analytical methods are mainly dictated by low concentrations found in aqueous and solid environmental samples. In the current article, a review of the liquid chromatography–tandem mass spectrometry (LC–MS/MS) based methods published so far for the determination of pharmaceuticals in the environment is presented. Pharmaceuticals included in this review are antibiotics, non-steroidal anti-inflammatory drugs, β-blockers, lipid regulating agents and psychiatric drugs. Advanced aspects of current LC–MS/MS methodology, including sample preparation and matrix effects, are discussed.; The work has been supported by the EU Project EMCO (INCO CT 2004-509188) and by the Spanish Ministerio de Ciencia y Tecnologia (PPQ2001-1805-CO3-01).; Peer reviewed

Comparative study of an estradiol enzyme-linked immunosorbent assay kit, liquid chromatography-tandem mass spectrometry, and ultra performance liquid chromatography-quadrupole time of flight mass spectrometry for part-per-trillion analysis of estrogens in water samples

Farré Urgell, Marinel.la; Kuster, Marina; Brix, Rikke; Rubio, Fernando; López de Alda, Miren; Barceló, Damià
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 19968 bytes; application/msword
ENG
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96.38%
10 pages, 5 tables.-- PMID: 17540393 [PubMed].-- Printed version published on Aug 10, 2207.-- Issue title: 23rd Montreux Symposium on Liquid Chromatography-Mass Spectrometry, Supercritical Fluid Chromatography-Mass Spectrometry, Capillary Electrophoresis-Mass Spectrometry and Tandem Mass Spectrometry (Montreaux, Switzerland, Nov 8-10, 2006).; Presented at the 2nd International Workshop on Liquid-Chromatography-Tandem Mass Spectrometry for Screening and Trace Level Quantitation in Environmental and Food Samples, Barcelona, Spain, September 18–19, 2006.; àáEstrogens have been often identified as the major contributors to the endocrine-disrupting activity observed in environmental waters. However, their analysis in these, sometimes very complex, matrices is still challenging due to the very low detection limits and the selectivity required for their reliable determination at the very low concentrations at which they are physiologically active. In this work, a polyclonal enzyme-linked immunosorbent assay (ELISA) kit for 17-prueba-estradiol analysis, high-performance liquid chromatography-tandem mass spectrometry (HPLC–MS/MS) based on triple-quadrupole analyzer (QqQ), and a newly developed method based on ultra performance liquid chromatography–quadrupole time of flight mass spectrometry (UPLC–Q-TOF-MS) have been evaluated in terms of performance for the rapid screening...

Application of liquid chromatography-electrospray-tandem mass spectrometry for the identification and characterisation of linear alkylbenzene sulfonates and sulfophenyl carboxylates in sludge-amended soils

Eichhorn, Peter; López Soler, Ángel; Barceló, Damià
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
Relevância na Pesquisa
96.19%
9 pages, 3 figures.-- PMID: 15844522 [PubMed].-- Printed version published Mar 4, 2005.-- Issue title: "Mass Spectrometry: Innovation and Application. Part IV".; A novel procedure was developed for the simultaneous determination of linear alkylbenzene sulfonates (LAS) and their major metabolites, sulfophenyl carboxylates (SPC), in sludge-amended soil. After pressurised liquid extraction with methanol/water (90:10) and a clean-up on C18 solid-phase extraction cartridges, final analysis was done by ion-pair liquid chromatography–electrospray–tandem mass spectrometry (LC–ESI–MS/MS). With this method, SPC with 5–13 carbon atoms in the aliphatic side chain were identified for the first time in agricultural soils treated with sewage sludge. Quantification of LAS and SPC in soil from 10 field sites, which differed in the history of sludge application, gave total concentrations of 120–2840 μg kg−1 for LAS and of 4–220 μg kg−1 for SPC. The data provided evidence for rapid biodegradation of LAS in the initial phase after sludge amendment with a transitory build-up of high concentrations of, mainly, short-chain SPC. Trace amounts of residual LAS and SPC were detected in soils having received the last sludge treatment 10 days to 4 years prior to sampling.; P. Eichhorn acknowledges a Marie Curie Individual Fellowship granted by the European Union (contract number: EVKI-CT-2001-50006).; Peer reviewed

Determination of pharmaceuticals of various therapeutic classes by solid-phase extraction and liquid chromatography–tandem mass spectrometry analysis in hospital effluent wastewaters

Gómez, M. José; Petrovic, Mira; Fernández Alba, Amadeo R.; Barceló, Damià
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 162 bytes; application/msword
ENG
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96.23%
10 pages, 3 figures, 3 tables.-- PMID: 16546199 [PubMed].-- Printed version published May 12, 2006.-- Issue title: ExTech 2005 - 7th International Symposium on Advances in Extraction Technologies (Campinas, Brazil, Nov 13-15, 2005).; Presented at the 1st International Workshop on Liquid Chromatography–Tandem Mass Spectrometry for Screening and Trace Level Quantitation in Environmental and Food Samples, Barcelona, Spain, 20–21 June 2005.; A multi-residue analytical method has been developed and validated for determining a selection of 16 pharmaceuticals: the anti-epileptic carbamazepine, seven analgesic/anti-inflammatory drugs (mefenamic acid, indomethacine, ibuprofen, naproxen, diclofenac, ketorolac and acetaminophen), the analgesic opiate codeine, two antidepressants (fluoxetine and paroxetine), β-blockers (atenolol and propranolol), antibiotic (trimethoprim, metronidazole, and erythromycin) and the anti-ulcer ranitidine in hospital effluent wastewaters. The method allows simultaneous extraction of the pharmaceuticals compounds by solid-phase extraction (SPE) using the Waters Oasis HLB at pH 7. The analytes were then identified and quantitatively determined by liquid chromatography–tandem mass spectrometry (LC–MS–MS) using multiple reaction monitoring (MRM). Recoveries of the pharmaceuticals were higher than 75%...