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Multi-residue and multi-class method for the determination of antibiotics in bovine muscle by ultra-high-performance liquid chromatography tandem mass spectrometry

Freitas, Andreia; Barbosa, Jorge; Ramos, Fernando
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
105.88%
A multi-residue quantitative screening method covering 41 antibiotics from 7 different families, by ultra-high-performance–liquid-chromatography tandem mass spectrometry (UHPLC–MS/MS), is described. Sulfonamides, trimethoprim, tetracyclines, macrolides, quinolones, penicillins and chloramphenicol are simultaneously detected after a simple sample preparation of bovine muscle optimized to achieve the best recovery for all compounds. A simple sample treatment was developed consisting in an extraction with a mixture of acetonitrile and ethylenediaminetetraacetic acid (EDTA), followed by a defatting step with n-hexane. The methodology was validated, in accordance with Decision 2002/657/EC by evaluating the required parameters: decision limit (CCα), detection capability (CCβ), specificity, repeatability and reproducibility. Precision in terms of relative standard deviation was under 20% for all compounds and the recoveries between 91% and 119%. CCα and CCβ were determined according the maximum residue limit (MRL) or the minimum required performance limit (MRPL), when required.

Desenvolvimento e caracterização de materiais baseados em sílica com aplicabilidade em extração em fase sólida e cromatografia líquida de ultra alta eficiência; Development and characterization of silica based materials with applicability in solid phase extraction and ultra high performance liquid chromatography

Nazário, Carlos Eduardo Domingues
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 21/01/2013 PT
Relevância na Pesquisa
106.04%
Atualmente, a demanda e a necessidade de metodologias analíticas e bioanalíticas que promovam análise rápida e seletiva tem impulsionado o constante desenvolvimento de sorventes para preparo de amostra e fases estacionárias para cromatografia líquida de alta eficiência (HPLC). Desta maneira, esta tese tem por objetivo desenvolver materiais utilizando precursores de sílica com aplicação em preparo de amostra e suportes cromatográficos para cromatografia líquida de ultra alta eficiência (UHPLC). Foram sintetizadas e caracterizadas duas fases extratoras as quais tiveram sua aplicabilidade demonstrada na extração de fármacos em fluidos biológicos empregando a técnica de extração em fase sólida (SPE). A primeira metodologia desenvolvida foi a síntese de partículas de sílica empregando precursores de baixo custo (silicato de sódio) pelo método sil-gel. Após a funcionalização com grupamento C18, e caracterização da fase extratora, o material sintetizado foi aplicado em SPE off-line para a determinação de fluoxetina e seu metabólito, norfluoxetina, em plasma humano por HPLC-UV. O método desenvolvido foi validado e aplicado em amostra de plasma de pacientes sob tratamento de fluoxetina. Além disso, o sorvente desenvolvido apresentou resultados similares quando comparado com fases extratoras comerciais. O segundo método desenvolvido utilizou a técnica de impressão molecular (MIP) a qual tem se tornado uma fase extratora atrativa devido a sua maior seletividade em relação as fases típicas empregadas em SPE. Ao mesmo tempo...

Avaliação da estabilidade de extratos hidroalcoólicos de Mikania laevigata e Mikania glomerata por cromatografia líquida de ultra eficiência acoplada a espectrometria de massas; Evaluation of the stability of hidroalcoholic extracts of Mikania laevigata and Mikania glomerata by Ultra-high performance liquid chromatography-mass spectrometry

Lucilia Vilela de Melo
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 02/08/2013 PT
Relevância na Pesquisa
105.91%
No Brasil, as espécies Mikania glomerata e Mikania laevigata, conhecidas popularmente como guaco, são muito utilizadas na forma de xarope devido ao seu efeito broncodilatador. A comercialização de medicamentos fitoterápicos no Brasil é regida por diversas legislações que primam pela qualidade destes, porém a qualidade da matéria-prima pode interferir de forma fundamental na segurança e eficácia do medicamento. Diante disso, este trabalho realizou um estudo de estabilidade do extrato hidroalcoólico das espécies citadas, conforme preconiza o "Guia para a realização de estudos de estabilidade de medicamentos" publicado pela ANVISA na RE 01, de 29 de julho de 2005. Folhas das duas espécies de Mikania foram secas em estufa a 40 °C e em liofilizador, foram preparados extratos hidroalcoólicos por maceração, que foram submetidos a estudo de estabilidade acelerado por 6 meses, e estudo de estabilidade de longa duração por 12 meses. As amostras ficaram armazenadas em diferentes temperaturas (22°C, 30°C e 40°C), com e sem incidência de luz, e a cada 3 meses foram analisadas por UHPLC-MS, para acompanhar seu perfil químico, quantificar a cumarina e ácido clorogênico. Em todas as condições do estudo, observou-se uma redução do teor do marcador químico desta espécie...

Análise da composição de amostras de própolis vermelha do Brasil por espectrometria de massas com ionização por eletrospray e cromatografia líquida de ultra-eficiência (UPLC-ESI-MS) e avaliação da atividade antioxidante e antimicrobiana = : Analysis of the composition of samples of red brazilian propolis by mass spectrometry with electrospray ionization and ultra high performance liquid chromatography (UPLC-ESI-MS) and evaluation of the antioxidant and antimicrobial activity; Analysis of the composition of samples of red brazilian propolis by mass spectrometry with electrospray ionization and ultra high performance liquid chromatography (UPLC-ESI-MS) and evaluation of the antioxidant and antimicrobial activity

Begoña Gimenez-Cassina Lopez
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 04/02/2014 PT
Relevância na Pesquisa
126.1%
A palavra própolis tem origem Grega: pro significa em defensa de, e polis significa comunidade. A própolis é usada pelas abelhas para fortalecer as paredes da colmeia e para cobrir as paredes internas e por devido a sua atividade antimicrobiana. A composição química da própolis é variável segundo a biodiversidade e a origem geográfica. A própolis vermelha, encontrada no nordeste e norte do Brasil, apresenta promissoras atividades biológicas: atividade antimicrobiana, antiparasitária, antioxidante, citotóxica, antiinflamatória, analgésica, efeitos antiobesidade, contra psoríase e hepatoprotetores. A composição química da própolis vermelha, relatada na literatura, parece variar qualitativa e quantitativamente, inclusive entre amostras coletadas na mesma região. Isto pode ser devido a variações sazonais, a flora direitamente ao redor das colméias ou aos métodos de análise. A maioria das classes de substâncias já identificadas pode ser analisada adequadamente por espectrometria de massas com ionização por eletrospray e cromatografia líquida. Os constituintes de média e alta polaridade (como fenólicos, flavonóides e benzofenonas) são responsáveis por muitas das atividades biológicas reportadas à própolis vermelha. A cromatografia líquida de ultra-eficiência acoplada à espectrometria de massas (UHPLC-MS) é um método moderno...

Quantification of LSD in illicit samples by high performance liquid chromatography

Marinho,Pablo Alves; Leite,Edna Maria Alvarez
Fonte: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2010 EN
Relevância na Pesquisa
125.91%
In the present study, a method using high performance liquid chromatography to quantify LSD, in blotter papers seized in Minas Gerais, was optimized and validated. Linearity, precision, recovery, limits of detection and quantification, and selectivity were the parameters used to evaluate performance. The samples were extracted with methanol:water (1: 1) in an ultra-sound bath. The linearity between 0.05 and 20.00 μg/mL (0.5 and 200.0μg of LSD/blotter) was observed with satisfactory mean intra and inter assay precision (RSDr = 4.4% and RSD R = 6.4%, respectively) and with mean recoveries of 83.4% and 84.9% to the levels of 1.00 and 20.00 μg/mL (10 and 200μg LSD/blotter). The limits of detection and quantification were 0.01 and 0.05 μg/mL, respectively (0.1 and 0.5 μg of LSD/blotter). The samples of blotters (n =22) were analyzed and the mean value of 67.55 μg of LSD/blotter (RSD=27.5%) was found. Thus, the method used showed satisfactory analytical performance, and proved suitable as an analytical tool for LSD determination in illicit samples seized by police forces.

Liquid-liquid extraction combined with high performance liquid chromatography-diode array-ultra-violet for simultaneous determination of antineoplastic drugs in plasma

Sanson,Ananda Lima; Silva,Suéllen Cristina Rennó; Martins,Matheus Coutinho Gonçalves; Giusti-Paiva,Alexandre; Maia,Patrícia Penido; Martins,Isarita
Fonte: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2011 EN
Relevância na Pesquisa
125.94%
A liquid-liquid extraction (LLE) combined with high-performance liquid chromatography-diode array detection method for simultaneous analysis of four chemically and structurally different antineoplastic drugs (cyclophosphamide, doxorubicin, 5-fluorouracil and ifosfamide) was developed. The assay was performed by isocratic elution, with a C18 column (5 µm, 250 x 4.6 mm) and mobile phase constituted by water pH 4.0- acetonitrile-methanol (68:19:13, v/v/v), which allowed satisfactory separation of the compounds of interest. LLE, with ethyl acetate, was used for sample clean-up with recoveries ranging from 60 to 98%. The linear ranges were from 0.5 to 100 µg mL-1, for doxorubicin and 1 to 100 µg mL-1, for the other compounds. The relative standard deviations ranged from 5.5 to 17.7%. This method is a fast and simple alternative that can be used, simultaneously, for the determination of the four drugs in plasma, with a range enabling quantification of the drugs in pharmacokinetics, bioequivalence and therapeutic drug-monitoring studies.

Standardization method for measurement of hydroxyurea by Ultra High Efficiency Liquid Chromatography in plasma of patients with sickle cell disease

Elias,Darcielle Bruna Dias; Carvalho,Teresa Maria de Jesus Ponte; Soares,Janete Eliza de Sá; Gonçalves,Romélia Pinheiro
Fonte: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2014 EN
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135.92%
Sickle cell anemia (SCA) is a recessively inherited disease characterized by chronic hemolytic anemia, chronic inflammation, and acute episodes of hemolysis. Hydroxyurea (HU) is widely used to increase the levels of fetal hemoglobin (HbF). The objective of this study was to standardize and validate a method for the quantification of HU in human plasma by using ultra high performance liquid chromatography (UPLC) in order to determine the plasma HU levels in adult patients with SCA who had been treated with HU. We used an analytical reverse phase column (Nucleosil C18) with a mobile phase consisting of acetonitrile/water (16.7/83.3). The retention times of HU, urea, and methylurea were 6.7, 7.7, and 11.4 min, respectively. All parameters of the validation process were defined. To determine the precision and accuracy of quality controls, HU in plasma was used at concentrations of 100, 740, and 1600 µM, with methylurea as the internal standard. Linearity was assessed in the range of 50-1600 µM HU in plasma, obtaining a correlation coefficient of 0.99. The method was accurate and precise and can be used for the quantitative determination of HU for therapeutic monitoring of patients with SCA treated with HU.

Use of Ultra High Performance Liquid Chromatography-Tandem Mass Spectrometry to Demonstrate Decreased Serum Statin Levels after Extracorporeal LDL-Cholesterol Elimination

Bláha, M.; Vlčková, H.; Nováková, L.; Solichová, D.; Solich, P.; Lánská, M.; Malý, J.; Bláha, V.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
105.86%
Background. Using our statin analysis method, it was possible to uncover a significant drop in statin levels (atorvastatin, simvastatin, and metabolites) after extracorporeal LDL-cholesterol elimination (EE) in severe familial hypercholesterolemia (FH). The purpose of this work was to identify the mechanism underlying this drop and its clinical significance as well as to propose measures to optimize a pharmacotherapeutical regimen that can prevent the loss of statins. Methods. Ultra High Performance Liquid Chromatography (UHPLC) connected to the triple quadrupole MS/MS system was used. Patients. A group of long-term treated patients (3–12 years of treatment) with severe FH (12 patients) and treated regularly by LDL-apheresis (immunoadsorption) or haemorheopheresis (cascade filtration) were included in this study. Results. After EE, the level of statins and their metabolites decreased (atorvastatin before/after LDL-apheresis: 8.83/3.46 nmol/l; before/after haemorheopheresis: 37.02/18.94 nmol/l). A specific loss was found (concentration of atorvastatin for LDL-apheresis/haemorheopheresis: 0.28/3.04 nmol/l in washing fluids; 11.07 nmol/l in filters). To prevent substantial loss of statin concentrations, a pharmacotherapeutic regimen with a longer time interval between the dose of statins and EE is recommended (15 hours). Conclusions. A specific loss of statins was found in adsorbent columns and filters. The decrease can be prevented by the suggested dosage scheme.

A Method for Multiple Mycotoxin Analysis in Wines by Solid Phase Extraction and Multifunctional Cartridge Purification, and Ultra-High-Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry

Tamura, Masayoshi; Takahashi, Ayumi; Uyama, Atsuo; Mochizuki, Naoki
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 15/06/2012 EN
Relevância na Pesquisa
105.87%
An analytical method using two solid phase extractions and ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed for the identification and quantification of 14 mycotoxins (patulin, deoxynivalenol, aflatoxins B1, B2, G1, G2, M1, T-2 toxin, HT-2 toxin, zearalenone, fumonisins B1, B2, B3, and ochratoxin A) in domestic and imported wines. Mycotoxins were purified with an Oasis HLB cartridge, followed by a MultiSepTM #229 Ochra. As a result, sufficient removal of the pigments and highly polar matrices from the red wines was achieved. UHPLC conditions were optimized, and 14 mycotoxins were separated in a total of 13 min. Determinations performed using this method produced high correlation coefficients for the 14 mycotoxins (R > 0.990) and recovery rates ranging from 76 to 105% with good repeatability (relative standard deviation RSD < 12%). Twenty-seven samples of domestic and imported wines were analyzed using this method. Although ochratoxin A (OTA) and fumonisins (FMs) were detected in several samples, the FM levels were less than limits of quantification (LOQs) (1 μg/L), and even the largest of the OTA levels was below the EU regulatory level (2 μg/L). These results suggest that the health risk posed to consumers from the wines available in Japan is relatively low.

Targeted Precise Quantification of 12 Human Recombinant Uridine-Diphosphate Glucuronosyl Transferase 1A and 2B Isoforms Using Nano-Ultra-High-Performance Liquid Chromatography/Tandem Mass Spectrometry with Selected Reaction Monitoring

Fallon, John K.; Neubert, Hendrik; Goosen, Theunis C.; Smith, Philip C.
Fonte: The American Society for Pharmacology and Experimental Therapeutics Publicador: The American Society for Pharmacology and Experimental Therapeutics
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
105.92%
Quantification methods employing stable isotope-labeled peptide standards and liquid chromatography–tandem mass spectrometry are increasingly being used to measure enzyme amounts in biologic samples. Isoform concentrations, combined with catalytic information, can be used in absorption, distribution, metabolism, and excretion studies to improve accuracy of in vitro/in vivo predictions. We quantified isoforms of uridine-diphosphate glucuronosyltransferase (UGT) 1A and 2B in 12 commercially available recombinant UGTs (recUGTs) (n = 49 samples) using nano-ultra-high-performance liquid chromatography–tandem mass spectrometry with selected reaction monitoring). Samples were trypsin-digested and analyzed using our previously published method. Two MRMs were collected per peptide and averaged. Where available, at least two peptides were measured per UGT isoform. The assay could detect UGTs in all recombinant preparations: recUGTs 1A1, 1A3, 1A4, 1A6, 1A7, 1A8, 1A9, 1A10, 2B4, 2B7, 2B15, and 2B17, with limit of detection below 1.0 pmol/mg protein for all isoforms. The assay had excellent linearity in the range observed (2–15.5 pmol/mg, after dilution). Examples of concentrations determined were 1465, 537, 538, 944, 865, 698, 604, 791, 382...

Biomonitoring method for bisphenol A in human urine by ultra-high-performance liquid chromatography-tandem mass spectrometry

Anderson, David J.; Brozek, Eric M.; Cox, Kyley J.; Porucznik, Christina A.; Wilkins, Diana G.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
105.93%
An ultra-high-performance liquid chromatography-tandem mass spectrometry method for the measurement of total bisphenol A in human urine was developed and validated. The method utilized liquid/liquid extraction with 1-chlorobutane and a human urine aliquot size of 800 µL. Chromatography was performed on an Acquity UPLC® system with a Kinetex® Phenyl-Hexyl column. Mass spectrometric analysis was with negative electrospray ionization on a Quattro Premier XE™. The surrogate matrix method was used for the preparation of calibration standards in synthetic urine due to the presence of BPA in control human urine. The validated calibration range was 0.75 to 20 ng/mL with a limit of detection of 0.1 ng/mL. The internal standard was d16-bisphenol A. Method validation utilized quality control samples at three concentrations in both synthetic urine and human urine. Bisphenol A mono-glucuronide was fortified in synthetic urine in each analytical run to monitor the enzymatic conversion of the glucuronide conjugate to BPA by β-glucuronidase. Validated method parameters included linearity, accuracy, precision, integrity of dilution, selectivity, re-injection reproducibility, recovery/matrix effect, solution stability, and matrix stability in human urine. Acceptance criteria for analytical standards and QCs were ± 20% of nominal concentration. Matrix stability in human urine was validated after 24 hours at ambient temperature...

Investigation of monomeric and oligomeric wine stilbenoids in red wines by ultra-high-performance liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry

Moss, R.; Mao, Q.; Taylor, D.; Saucier, C.
Fonte: John Wiley & Sons Ltd Publicador: John Wiley & Sons Ltd
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
115.9%
RATIONALE: Stilbenoids are secondary plant metabolites responsible for the protection of multiple plant species including grape vine from bacterial and fungal infection. Red wine has been shown to be a major source of these compounds in the human diet, where they display an array of health benefits. Providing a more complete profile of the stilbenoids present in red wine, this study detects 41 stilbenoid compounds, 23 of which have never before been detected in red wine. METHODS: Red wine extracts were scanned using an ultra-high-performance liquid chromatograph coupled to a hybrid quadrupole time-of-flight mass analyzer. Multiple targeted MS/MS precursor ion scan experiments were performed using electrospray ionization operated in negative mode. Precursor ion masses were scanned for the monomeric and oligomeric stilbenoids, as well as modifications such as O-glycosylation, methoxylation and oxidation products of these compounds. Accurate mass precursor and characteristic product ions afforded partial structural elucidation and assignment of these compounds. RESULTS: A total of 41 (both known and novel) stilbenoids were detected in extracted red wine. In addition to the well-known monomeric stilbenes, several resveratrol-resveratrol homodimers (m/z 453.1344)...

A sensitive microextraction by packed sorbent-based methodology combined with ultra-high pressure liquid chromatography as a powerful technique for analysis of biologically active flavonols in wines

Silva, Catarina L.; Gonçalves, João L.; Câmara, José S.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /08/2012 ENG
Relevância na Pesquisa
125.93%
A new approach based on microextraction by packed sorbent (MEPS) and reversed-phase high-throughput ultra high pressure liquid chromatography (UHPLC) method that uses a gradient elution and diode array detection to quantitate three biologically active flavonols in wines, myricetin, quercetin, and kaempferol, is described. In addition to performing routine experiments to establish the validity of the assay to internationally accepted criteria (selectivity, linearity, sensitivity, precision, accuracy), experiments are included to assess the effect of the important experimental parameters such as the type of sorbent material (C2, C8, C18, SIL, and C8/SCX), number of extraction cycles (extract-discard), elution volume, sample volume, and ethanol content, on the MEPS performance. The optimal conditions of MEPS extraction were obtained using C8 sorbent and small sample volumes (250 μL) in five extraction cycle and in a short time period (about 5 min for the entire sample preparation step). Under optimized conditions, excellent linearity View the MathML source(Rvalues2>0.9963), limits of detection of 0.006 μg mL−1 (quercetin) to 0.013 μg mL−1 (myricetin) and precision within 0.5–3.1% were observed for the target flavonols. The average recoveries of myricetin...

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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106.08%
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...

Identification of unknown pesticides in fruits using ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry Imazalil as a case study of quantification

Picó, Yolanda; Farré Urgell, Marinel.la; Soler, Carla; Barceló, Damià
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 19968 bytes; application/msword
ENG
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136%
12 pages, 5 tables, 6 figures.-- PMID: 18021786 [PubMed].-- Printed version published on Dec 28, 2007.; Ultra-high-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (UPLC-QqTOF-MS) is an emerging technique offering more rapid and efficient separation, as well as the possibility to obtain accurate mass measurement and tandem mass spectrometry (MS/MS). This paper deals with the use of UPLC-QqTOF-MS to identify the pesticide residues present in complex pear extracts. Carbendazim, imazalil, and ethoxyquin were successfully identified because of the accurate mass determination of their protonated molecule and their major fragments in the product ion mass spectra. A few plastic and latex additives were also found, most of them probably coming from the packaging transfer to the fruits. The potential of the UPLC-QqTOF-MS and UPLC-QqTOF-MS/MS techniques as a quantification tool is also discussed taking imazalil as example. For quantification, calibration curves were linear over a dynamic range of 2 orders of magnitude, whereas higher calibration ranges are better adjusted to polynomial curves of second and third order. Quantification using different mass windows was also assessed. Accurate quantification required mass windows as wide as 20 mDa...

Multi-residue analysis of pharmaceuticals in wastewater by ultra-performance liquid chromatography–quadrupole–time-of-flight mass spectrometry

Petrovic, Mira; Gros, Meritxell; Barceló, Damià
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 162 bytes; application/msword
ENG
Relevância na Pesquisa
105.99%
14 pages, 5 figures, 5 tables.-- PMID: 16759662 [PubMed].-- Printed version published Aug 18, 2006.-- Issue title: ExTech 2006 - 8th International Symposium on Advances in Extraction Techniques (York, UK, Feb 6-8, 2006).; In this work, a new multi-residue method using ultra-performance liquid chromatography (UPLC) quadrupole-time-of-flight mass spectrometry (Q–TOF–MS) was developed for screening and confirmation of 29 pharmaceutical compounds belonging to different therapeutical classes: analgesics and antiinflammatories, lipid regulating agents cholesterol lowering statin agents, psychiatric drugs, anti ulcer agents, histamine H2 receptor antagonist, antibiotics and beta-blockers. UPLC uses columns packed with 1.7 μm particles and enables elution of sample components in much narrower, more concentrated bands, resulting in better chromatographic resolution and increased peak height. The typical peak width was 5–10 s at base, permitting very good separation of all compounds in 10 min, which represented an approximate three-fold reduction in the analysis time in comparison to conventional high-performance liquid chromatography (HPLC). Unequivocal identification of target pharmaceutical compounds was based on accurate mass measurement of the molecular ions in the TOF mode and by performing collision induced dissociation (CID) in the Q–TOF mode in order to generate accurate mass measurement of the product ions. Using lock mass correction the accurate masses calculated for the product ions deviated from the theoretical masses by 0.2 to 1.3 mDa (root mean square (RMS) value = 0.67) and 0.7–6.4 ppm (RMS = 3.53)...

Quantification of LSD in illicit samples by high performance liquid chromatography

Marinho, Pablo Alves; Leite, Edna Maria Alvarez
Fonte: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/12/2010 ENG
Relevância na Pesquisa
125.97%
No presente trabalho, um método utilizando cromatografia líquida de alta eficiência foi otimizado e validado para quantificar o LSD em selos apreendidos em Minas Gerais. A linearidade, precisão, recuperação, limites de detecção e quantificação e seletividade foram os parâmetros de desempenho avaliados. As amostras foram extraídas com metanol: água (1:1) em banho de ultra-som. A linearidade entre 0,05 a 20,00 mg/mL (0,5 a 200 μg LSD/blotter) foi observada com precisão média, intra e inter ensaio, satisfatória (RSDr = 4,4% e RSD R = 6,4%, respectivamente) e com recuperações médias de 83,4% e 84,9% para os níveis de LSD de 1,00 e 20,00 mg/mL (10 e 200 μg LSD/selo). Os limites de detecção e quantificação encontrados foram de 0,01 e 0,05 mg/mL, respectivamente (0,1 e 0,5 μg LSD/selo). As amostras de selos (n = 22) foram analisadas e o valor médio encontrado foi de 67,55 μg de LSD/selo (RSD% = 27,5). Desta forma, o método analítico apresentou desempenho satisfatório, capaz de ser utilizado como instrumento de análise para a determinação do LSD em amostras ilícitas apreendidas pelas forças policiais.; In the present study, a method using high performance liquid chromatography to quantify LSD...

Liquid-liquid extraction combined with high performance liquid chromatography-diode array-ultra-violet for simultaneous determination of antineoplastic drugs in plasma

Sanson, Ananda Lima; Silva, Suéllen Cristina Rennó; Martins, Matheus Coutinho Gonçalves; Giusti-Paiva, Alexandre; Maia, Patrícia Penido; Martins, Isarita
Fonte: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo. Faculdade de Ciências Farmacêuticas
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/06/2011 ENG
Relevância na Pesquisa
125.94%
Um método de extração líquido-líquido (ELL) combinado com cromatografia líquida de alta eficiência-detector de arranjo de diodos foi desenvolvido para análise simultânea de quatro fármacos antineoplásicos quimicamente e estruturalmente diferentes (ciclofosfamida, doxorrubicina, fluoruracila e ifosfamida). O estudo foi realizado sob condições isocráticas, com coluna C18 (5µm, 250 x 4.6 mm) e fase móvel constituída por água pH 4.0-acetonitrila-metanol (68:19:13, v/v/v), que permitiu separação satisfatória dos analitos de interesse. A ELL, com acetato de etila, foi utilizada para limpeza da amostra, com recuperação variando de 60 a 98%. As faixas foram lineares de 0,5 a 100 µg mL-1 para doxorrubicina e 1 a 100 µg mL-1 para os outros compostos. O desvio padrão relativo variou de 5,5 a 17,7%. Este método é uma alternativa rápida e simples que pode ser usado, simultaneamente, para a determinação dos quatro fármacos em plasma, com uma faixa que permite quantificá-los em estudos de farmacocinética, bioequivalência e monitorização terapêutica.; A liquid-liquid extraction (LLE) combined with high-performance liquid chromatography-diode array detection method for simultaneous analysis of four chemically and structurally different antineoplastic drugs (cyclophosphamide...

A fast method using a new hydrophilic–lipophilic balanced sorbent in combination with ultra-high performance liquid chromatography for quantification of significant bioactive metabolites in wines

Silva, Catarina L.; Pereira, Jorge; Wouter, Van G.; Giró, Carme; Câmara, José S.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em /10/2011 ENG
Relevância na Pesquisa
156.04%
This manuscript describes the development and validation of an ultra-fast, efficient, and high throughput analytical method based on ultra-high performance liquid chromatography (UHPLC) equipped with a photodiode array (PDA) detection system, for the simultaneous analysis of fifteen bioactive metabolites: gallic acid, protocatechuic acid, (−)-catechin, gentisic acid, (−)-epicatechin, syringic acid, p-coumaric acid, ferulic acid, m-coumaric acid, rutin, trans-resveratrol, myricetin, quercetin, cinnamic acid and kaempferol, in wines. A 50-mm column packed with 1.7-μm particles operating at elevated pressure (UHPLC strategy) was selected to attain ultra-fast analysis and highly efficient separations. In order to reduce the complexity of wine extract and improve the recovery efficiency, a reverse-phase solid-phase extraction (SPE) procedure using as sorbent a new macroporous copolymer made from a balanced ratio of two monomers, the lipophilic divinylbenzene and the hydrophilic N-vinylpyrrolidone (Oasis™ HLB), was performed prior to UHPLC–PDA analysis. The calibration curves of bioactive metabolites showed good linearity within the established range. Limits of detection (LOD) and quantification (LOQ) ranged from 0.006 μg mL−1 to 0.58 μg mL−1...

Determination of Triclosan and Ketoprofen in River Water and Wastewater by Solid Phase Extraction and High Performance Liquid Chromatography

Madikizela,Lawrence M.; Muthwa,Sindisiwe F.; Chimuka,Luke
Fonte: South African Journal of Chemistry Publicador: South African Journal of Chemistry
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
Relevância na Pesquisa
125.88%
This paper describes a simple, sensitive and rapid method for the determination of triclosan and ketoprofen in wastewater influent, effluent and river water. The method involves solid phase extraction (SPE) of target compounds using Oasis HLB sorbent. Several extraction parameters such as sample pH, sample volume, SPE cartridge and SPE elution solvent were optimized. The pH of the collected samples was adjusted to 5.5, and then 100 mL of the sample was loaded into an Oasis HLB cartridge. Methanol was used to elute the retained compounds. The eluted compounds were analyzed using reversed-phase high performance liquid chromatography with photo diode array detection (HPLC-PDA). The method was validated by spiking ultra-pure water and wastewater with different concentrations of both compounds ranging from 5 ju,g L-1 to 1000ju,g L-1. Recoveries were in the range of 73 % to 104 %, and % RSD ranged from 8%to15%. The method gave good detection limits of 0.01 and 0.08 ju,g L-1 for triclosan and ketoprofen, respectively. Traces of both compounds were detected in all wastewater (influent and effluent) samples at a range of 1.2 to 9.0 ju,g L-1 and in some river water samples.