999 resultados para CE-MS


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CE-MS has been increasingly used for analysis of a vast array of compounds. This article reviews the different electrophoretic modes, interfaces and mass analyzers that are commonly used in the CE-MS coupling, as well as the technique advantages and performance characteristics. A large compilation of CE-MS applications is also presented. Therefore, this review is both a guide for beginners and a collection of key references for people who are familiar to the technique. Furthermore, this is the first CE-MS review published in a Brazilian journal and marks the installation of the first two commercial CE-MS units in Sao Paulo State.

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CE-MS has been increasingly used for analysis of a vast array of compounds. This article reviews the different electrophoretic modes, interfaces and mass analyzers that are commonly used in the CE-MS coupling, as well as the technique advantages and performance characteristics. A large compilation of CE-MS applications is also presented. Therefore, this review is both a guide for beginners and a collection of key references for people who are familiar to the technique. Furthermore, this is the first CE-MS review published in a Brazilian journal and marks the installation of the first two commercial CE-MS units in Sao Paulo State.

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There is a need of scientific evidence of claimed nutraceutical effects, but also there is a social movement towards the use of natural products and among them algae are seen as rich resources. Within this scenario, the development of methodology for rapid and reliable assessment of markers of efficiency and security of these extracts is necessary. The rat treated with streptozotocin has been proposed as the most appropriate model of systemic oxidative stress for studying antioxidant therapies. Cystoseira is a brown alga containing fucoxanthin and other carothenes whose pressure-assisted extracts were assayed to discover a possible beneficial effect on complications related to diabetes evolution in an acute but short-term model. Urine was selected as the sample and CE-TOF-MS as the analytical technique to obtain the fingerprints in a non-target metabolomic approach. Multivariate data analysis revealed a good clustering of the groups and permitted the putative assignment of compounds statistically significant in the classification. Interestingly a group of compounds associated to lysine glycation and cleavage from proteins was found to be increased in diabetic animals receiving vehicle as compared to control animals receiving vehicle (N6, N6, N6-trimethyl-L-lysine, N-methylnicotinamide, galactosylhydroxylysine, L-carnitine, N6-acetyl-N6-hydroxylysine, fructose-lysine, pipecolic acid, urocanic acid, amino-isobutanoate, formylisoglutamine. Fructoselysine significantly decreased after the treatment changing from a 24% increase to a 19% decrease. CE-MS fingerprinting of urine has provided a group of compounds different to those detected with other techniques and therefore proves the necessity of a cross-platform analysis to obtain a broad view of biological samples.

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Protein hydrolysates have been used as active principles in cosmetic products conferring different properties to the final formulations, which are mostly controlled by the peptide size and its amino acid sequence. In this work, capillary electrophoresis coupled to mass spectrometry analyses were carried out in order to investigate such characteristics of protein hydrolysates. Samples of different origins (milk, soy and rice) were obtained from a local company, and were analyzed without a previous preparation step. The background electrolyte (BGE) and sheath liquid compositions were optimized for each sample. The best BGE composition (860 mmol/L formic acid - pH 1.8 - in 70: 30 v/v water/methanol hydro-organic solvent) was chosen based on the overall peak resolution whereas the best sheath liquid was selected based on increased sensitivity and presented different compositions to each sample (10.9-217 mmol/L formic acid in 75: 25-25: 75 v/v water/methanol hydro-organic solvent). Most of the putative peptides in the hydrolysate samples under investigation presented molecular masses of 1000 Da or less. De novo sequencing was carried out for some of the analytes, revealing the hydrophobicity/polarity of the peptides. Hence, the technique has proved to be an advantageous tool for the quality control of industrial protein hydrolysates.

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Metabolite identification and metabolite profiling are of major importance in the pharmaceutical and clinical context. However, highly polar and ionic substances are rarely included as analytical tools are missing. In this study, we present a new method for the determination of urinary sulfates, sulfonates, phosphates and other anions of strong acids. The method comprises a CE separation using an acidic BGE (pHCE-MS can be used for determination of this alcohol consumption marker. An SPE method was developed for the extraction of ethyl sulfate and other organic anions. Several additional compounds can be identified based on the accurate mass determined by the TOF MS in conjunction with databases. However, numerous detected compounds have not been reported in urinary metabolite databases so far. Thus, it is demonstrated that the presented method is complementary to the existing methods for metabolite characterization in urine.

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in this work, a simple method for the simultaneous determination of cocaine (COC) and five COC metabolites (benzoylecgonine, cocaethylene (CET), anhydroecgonine, anhydroecgonine methyl ester and ecgonine methyl ester) in human urine using CE coupled to MS via electrospray ionization (CE-ESI-MS) was developed and validated. Formic acid at 1 mol/L concentration was used as electrolyte whereas formic acid at 0.05 mol/L concentration in 1:1 methanol:water composed the coaxial sheath liquid at the ESI nozzle. The developed method presented good linearity in the dynamic range from 250 ng/mL to 5000 ng/mL (coefficient of determination greater than 0.98 for all compounds). LODs (signal-to-noise ratio of 3) were 100 ng/mL for COC and CET and 250 ng/mL for the other studied metabolites whereas LOQ`s (signal-to-noise ratio of 10) were 250 ng/mL for COC and CET and 500 ng/mL for all other compounds. Intra-day precision and recovery tests estimated at three different concentration levels (500, 1500 and 5000 ng/mL) provided RSD lower than 10% (except anhydroecgonine, 18% RSD) and recoveries from 83-109% for all analytes. The method was successfully applied to real cases. For the positive urine samples, the presence of COC and its` metabolites was further confirmed by MS/MS experiments.

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Même ornementation, mêmes armoiries que dans le ms. français 5094. Le texte de ce ms., qui offre en plusieurs endroits des lacunes que nous indiquerons dans un instant, donne au feuillet 5 v° une strophe de 8 vers qui n'existe pas dans les exemplaires précédents : « Ensemble furent si bien d'accord Qu'ilz engendrèrent un fils de grant noblesse, Nommé Jehan, dit conte de Monfort, Après la mort de la noble duchesse, Et quatre filles qui en grant leesse Furent toutes colloquées haultement, Car de France, la royalle haultesse, Fut descendue la noble Yollant » . Quant aux lacunes, en voici l'énumération : Fol. 31. Ce feuillet est mutilé de la marge droite, de sorte qu'il ne donne pas les deux écussons coloriés qui accompagnent dans les autres mss. la notice relative à Étampes et à Hue Le Maire, sieur de Chaillou. — Entre les feuillets 33 et 34 est une lacune qui correspond aux 4 vers relatifs à N.-D. des Champs, au départ du corps de la reine de l'église N.-D. des Champs, le 14 février 1514, jusqu'aux premières lignes du sermon prononcé à St-Denis par M. Parvy, confesseur de la reine, le 16 février 1514, là où l'orateur donne l'origine de l'hermine qui figure dans les armes de Bretagne, soit en tout une lacune de 18 pages. — Au revers du feuillet 42 devrait être une miniature représentant la « chapelle royalle ardant » en l'église des Carmes, à Nantes, où fut déposé le coeur d'Anne de Bretagne. Cette miniature n'a pas été exécutée, et la place est restée en blanc. Après cette miniature existent dans les autres mss. 20 vers qui ne figurent pas dans le présent ms. — Entre les feuillets 44 et 45 manquent 31 lignes, soit la valeur d'une page et 6 lignes, qui commencent par l'épitaphe de François II, duc de Bretagne : « Si dedans gist le corps du duc Françoys, deuxe de ce nom, lequel regna trente deux... », et finissent par la description du coeur d'or contenant le coeur d'Anne de Bretagne, dont la portraiture, qui existe dans les mss. précédents, manque dans celui-ci. — Les 38 lignes qui forment la fin de notre relation dans les mss. précédents, manquent dans celui-ci, qui s'arrête avec la phrase : « Ainsy finirent iceulx services, mais les pleurs, criz et lamentacions auront longue durée. Prions Dieu pour elle, celluy qui son ame a créé ».

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Aromatic amines are widely used industrial chemicals as their major sources in the environment include several chemical industry sectors such as oil refining, synthetic polymers, dyes, adhesives, rubbers, perfume, pharmaceuticals, pesticides and explosives. They result also from diesel exhaust, combustion of wood chips and rubber and tobacco smoke. Some types of aromatic amines are generated during cooking, special grilled meat and fish, as well. The intensive use and production of these compounds explains its occurrence in the environment such as in air, water and soil, thereby creating a potential for human exposure. Since aromatic amines are potential carcinogenic and toxic agents, they constitute an important class of environmental pollutants of enormous concern, which efficient removal is a crucial task for researchers, so several methods have been investigated and applied. In this chapter the types and general properties of aromatic amine compounds are reviewed. As aromatic amines are continuously entering the environment from various sources and have been designated as high priority pollutants, their presence in the environment must be monitored at concentration levels lower than 30 mg L1, compatible with the limits allowed by the regulations. Consequently, most relevant analytical methods to detect the aromatic amines composition in environmental matrices, and for monitoring their degradation, are essential and will be presented. Those include Spectroscopy, namely UV/visible and Fourier Transform Infrared Spectroscopy (FTIR); Chromatography, in particular Thin Layer (TLC), High Performance Liquid (HPLC) and Gas chromatography (GC); Capillary electrophoresis (CE); Mass spectrometry (MS) and combination of different methods including GC-MS, HPLC-MS and CE-MS. Choosing the best methods depend on their availability, costs, detection limit and sample concentration, which sometimes need to be concentrate or pretreated. However, combined methods may give more complete results based on the complementary information. The environmental impact, toxicity and carcinogenicity of many aromatic amines have been reported and are emphasized in this chapter too. Lately, the conventional aromatic amines degradation and the alternative biodegradation processes are highlighted. Parameters affecting biodegradation, role of different electron acceptors in aerobic and anaerobic biodegradation and kinetics are discussed. Conventional processes including extraction, adsorption onto activated carbon, chemical oxidation, advanced oxidation, electrochemical techniques and irradiation suffer from drawbacks including high costs, formation of hazardous by-products and low efficiency. Biological processes, taking advantage of the naturally processes occurring in environment, have been developed and tested, proved as an economic, energy efficient and environmentally feasible alternative. Aerobic biodegradation is one of the most promising techniques for aromatic amines remediation, but has the drawback of aromatic amines autooxidation once they are exposed to oxygen, instead of their degradation. Higher costs, especially due to power consumption for aeration, can also limit its application. Anaerobic degradation technology is the novel path for treatment of a wide variety of aromatic amines, including industrial wastewater, and will be discussed. However, some are difficult to degrade under anaerobic conditions and, thus, other electron acceptors such as nitrate, iron, sulphate, manganese and carbonate have, alternatively, been tested.

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F. 1-8v Fragments d'un graduel : — ss. Marcus et Marcellianus (1) ; — Messe de l'Invention de la Sainte Croix (8v). F. 9-61v Fragments d'un bréviaire (lacunes et ff. intervertis) : — 3e Dim. de Carême (incompl.) (9) ; — s. Paul (incompl.) (18) ; — Rameaux (30) ; — s. Maurice (addit. XIIe s.) (39) ; — 9e Dim. après la Pentecôte (43) ; — ste Marie-Madeleine (58v). Offices à 9 leçons (usage de Limoges, d'après les répons des 3 derniers jours de la semaine sainte).

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Acquis le 8-12 floréal an VIII (28 avril-2 mai 1804), envoyé de la ville de Sens et remis au département des Manuscrits par le conservateur Millin, et placé dans le grenier du Levant à la suite des mss. venus de Compiègne; cf. B.n.F., département des Manuscrits, Archives Modernes 492, registre des acquisitions du département des Manuscrits an II-an XIV (1793-1805), f. 107 "Biblia sacra metrica a Petro de Riga, cod. memb. s. XIV exaratus in fol."; Delisle, Cab. des mss., II, 15; — ne provient pas de l'abbaye d'Orval (dioc. de Trèves), contrairement à l'avis de Delisle qui a confondu ce ms. et le latin 9749, cf. Cab. des mss., II, 389; A.-C. Fraeijs de Veubeke, Scriptorium, 31, 1977, 348 et 27, 1973, 106 (catalogue des mss. subsistants d'Orval) mais de l'abbaye de Vaux-Luisant, cf. latin 9562

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Le complément de ce ms. se trouve dans le n. 15536.

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On a joint à la fin du volume une notice, par M. Félis, sur quelques-uns des compositeurs des pièces contenues dans ce ms. (Autographe.)

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Abdo et Sennes (262-263v) ; Acisclus et Victoria (163-165) ; Adrianus (72v-77) ; Affra (45v) ; Amancius (122-125v) ; Andochius (90v-92v) ; Andreas (186-194v) ; Antoninus (68v-70v, 221v) ; Apollinaris (1bis-1bis v); Audardus (254-259) ; Augustinus (231-232v) ; Bartholomeus (55v-59v) ; Bricius Turonensis (162v-163) ; Caprasius (107-108) ; Caprasius et Fides (218-219v) ; Cassianus (48v) ; Cecilia (168v-174v) ; Christina (12-16v) ; Christoforus (22-24) ; Ciricus et Julita (2v-6, 260v-262) ; Cirillus (2-2v) ; Ciprianus (47v-48v) ; Claudius, Asterius, Neo (54v-55v) ; Clemens (174v-176) ; Cosmas et Damianus (97v-98v) ; Crisantus et Daria (179-182v) ; Crucis exaltatio (83-84) ; Cucufas (24-25) ; Dalmacius Rutenae urbis (131-132v) ; Desiderius Caturcensis (207v-217v) ; Dionisius (105-106v) ; Donatus (263v-265v) ; Eleazarus (38-38v) ; Eptadius (59v-61v) ; Eufemia (84-86) ; Eugenia (78-83) ; Eulalia (195v-199) ; Eustachius (125v-129v) ; Fabius (34v-36v) ; Fausta (52-53v) ; Faustus, Januarius et Marcialis (106v-107) ; Felix (36v-38) ; Felix Nolensis ep. (25-27) ; Filibertus (227v-231) ; Genesius Arelatensis (61v-62v) ; Germanus Autissiodorensis (33-34) ; Gervasius et Protasius (259v-260v) ; Gregorius papa (222-224v) ; Grisogonus (176v-178) ; Jacobus major (20v-21v) ; Jeronimus (100-102) ; Johannis Baptistae decollatio (66v-68v) ; Johannes et Paulus (227-227v) ; Julia (11-12) ; Julianus (64-64v) ; Julianus, auct. Gregorio Turonense (265v-272) ; Julius (178-178v) ; Justa et Rufina (6v-7) ; Justina et Ciprianus (92v-97v) ; Justus et Pastor (44v-45) ; Laurianus (167v-168v) ; Leochadia (195-195v) ; Leodegarius (102-104v) ; Licerius (62v-64) ; Longinus (195) ; Lucia (199-200v) ; Machabei (34-34v) ; Mammes (45v-47v) ; Marcellinus et Petrus (259-259v) ; Marcellus (114) ; Marcellus Cavalonis (219v-220) ; Marcellus Kavilonensis (1v-1bis) ; Marcus (224v-225) ; Marciana (129v-131) ; Marcianus (206-206v) ; Margarita (7-11) ; Mariae assumptio (48v-51) ; Martinus, auct. Sulpicio Severo (133-160v) ; Matheus (86-89) ; Mauricius (89-90v) ; Mauricius, Exuperius, Candidus, Innocentius, Victor cum sociis eorum (272-272v) ; Maurinus (245-247v) ; Maximus (241-244v) ; Medardus (225-227) ; Mennas (160v-162v) ; Michael (98v-100) ; Mimius (39v-40) ; Nazarius et Celsus (27-31v) ; Omnes Sancti (118v-122) ; Pantaleo (31v-32v) ; Petri cathedra (220-221v, 249-250) ; Petrus, ep. Alexandriae (248-249) ; Procopius (39-39v) ; Quintinus (114-118v) ; Regina (70v-72v) ; Reparata (104v-105) ; Romanus (165-167) ; Sabina (64v-66v) ; Salvius (77-78) ; Saturninus et Sisinnius (178v) ; Saturninus Tolosanensis (182v-185v, 232v-239) ; Segolena (16v-20v) ; Servandus et Germanus (108-109) ; Sixtus, Laurentius et Ypolitus (40-44v); Symo et Judas (109-112v) ; Symphorianus (53v-54v) ; Teodota (38v-39) ; Terencianus (239-241) ; Theodardus Narbonensis (250-254) ; Thomas (200v-206) ; Valerianus (206v-207) ; Vamnes (51-52) ; Vincentius et Savina (112v-114). Le f. 220v contient un catalogue ancien de la bibliothèque de Moissac.

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Dans cette copie le bāb 45 est numéroté 46 par erreur, de même que la date de composition (f. 66v) est donnée comme étant 700H.[sic] au lieu de 795H. De la main de Muḥ. Zamān, on trouve des gloses lexicographiques entre les lignes ou dans le marges. La signature d’Aussant figure au f. 1. Ce ms. (Aussant n° 38) a été acquis par la B.N. en 1798. [Anc. cote, Suppl. persan 51].