Column C18
Mostrando 1-12 de 337 artigos, teses e dissertações.
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1. Determinação de etil-glicuronídeo e etil-sulfato em sangue por UPLC-MS/MS: aplicação clínica em vítimas de trauma
We developed a UPLC-MS/MS method for the quantification of the ethanol metabolites ethyl-glucuronide (EtG) and ethyl-sulfate (EtS) in blood samples. Sample preparation was a protein precipitation with acetonitrile 0.1% formic acid containing internal standards (IS) 0.5 µg mL-1 EtG-D5 and EtS-D5. Chromatographic separation was performed in a fluoro-phenyl co
Química Nova. Publicado em: 2022
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2. Methodology Development and Validation of Amphotericin B Stability by HPLC-DAD
The high worldwide consumption of antibiotics and their complex impurity profiles has drawn the attention of the scientific community to the development and validation of stability methods for these drugs. Amphotericin B is an antibiotic that is a natural fermentation product of bacterium Streptomyces nodosus, used as a broad-spectrum antifungal agent, and i
J. Braz. Chem. Soc.. Publicado em: 2020-05
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3. Determination of Methanol in Gasoline and Ethanol Fuels by High-Performance Liquid Chromatography
Gasoline and ethanol fuels have been adulterated with methanol in Brazil. Methanol is not permitted in concentrations greater than 0.5 vol% due its toxicity but its lower price stimulates the adulteration. A new approach for quantitative analysis of methanol in gasoline and ethanol fuels is reported employing high-performance liquid chromatography coupled wi
J. Braz. Chem. Soc.. Publicado em: 2020-05
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4. Determinação de docetaxel e metabólitos em plasma por UPLC-MS/MS: desenvolvimento de metodologia analítica e aplicação clínica
A highly sensitive ultra-performance liquid chromatography tandem mass spectrometry method for the determination of Docetaxel and metabolites (M1+M3) in human plasma samples was developed and validated. The method employs a liquid-liquid extraction and a reversed phase separation Acquity® C18 column BEH C18 (150 x 2.1 mm, 1.7 µm). Mobile phase was a mixtur
Quím. Nova. Publicado em: 2020-04
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5. AVALIAÇÃO DE ADITIVOS DE FASE MÓVEL E TEMPERATURA NA VIDA ÚTIL DE COLUNAS PARA CROMATOGRAFIA LÍQUIDA DE ALTA EFICIÊNCIA
Buffered solutions, additives, and column temperature are widely used in high-performance liquid chromatography to promote adequate retention of compounds and to improve the chromatographic separation. However, these factors can dramatically reduce the column lifetime. In this work, the effect of column temperature, pH and the salt type and concentration in
Quím. Nova. Publicado em: 2020-03
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6. Simultaneous determination of anti-diabetic drugs
A novel reverse phase, isocratic HPLC method is described to separate five anti-diabetic drugs i.e., glimepiride, metformin, sitagliptin, rosiglitazone and pioglitazone. Nucleosil C18 analytical column was used as stationary phase, while mobile phase consisted of acetonitrile:phosphate buffer: methanol (40/40/20, v/v) pH 2.0. Effluent was monitored at a flow
Braz. J. Pharm. Sci.. Publicado em: 20/12/2019
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7. Simultaneous liquid chromatography- tandem mass spectrometry method to quantify epicatechin and procyanidin B2 in rat plasma after oral administration of Trichilia catigua (catuaba) extract and its application to a pharmacokinetic study
Abstract Trichilia catigua A. Juss., Meliaceae, known as catuaba in Brazil, is traditionally used for the treatment of stress, sexual impotence and memory deficits. To our knowledge, there is no analytical method described in literature for simultaneous quantification of catuaba extract marker substances in biological matrices. The aim of this study was to d
Rev. bras. farmacogn.. Publicado em: 17/10/2019
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8. Validated analytical study of the effect of Lycopene on the pharmacokinetics of Paracetamol and Chlorzoxazone in rats
Lycopene was reported to influence some cytochrome P450 enzymes activity. The present study investigates the effect of lycopene on the pharmacokinetics of paracetamol and chlorzoxazone. Lycopene (20 mg/kg) was intra-peritoneally administered to two groups of rats for eight consecutive days and two other groups were given vehicle. On the eighth day, chlorzoxa
Braz. J. Pharm. Sci.. Publicado em: 03/10/2019
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9. LC-UV method to assay raloxifene hydrochloride in rat plasma and its application to a pharmacokinetic study
A specific, precise, and accurate LC-UV method was developed and validated to assay raloxifene hydrochloride in rat plasma. Raloxifene was analyzed after liquid-liquid extraction and quantified by reversed phase liquid chromatography (C18 column) using acetonitrile and ammonium acetate buffer 0.05 M (pH 4.0) as mobile phase at a flow rate of 1 mL.min-1 and U
Braz. J. Pharm. Sci.. Publicado em: 30/09/2019
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10. HPLC-PDA method validated for the determination of hibalactone in Hydrocotyle umbellata subterraneous parts and its ultrasound-assisted extraction optimization
ABSTRACT In this work, we developed and validated a HPLC-PDA method for the quantification of hibalactone in Hydrocotyle umbellata L., Araliaceae, subterraneous parts extracts and optimized its ultrasound-assisted extraction. Chromatographic separations were carried out with an isocratic mobile phase of acetonitrile/methanol/water (10:65:25), a flow of 0.8 m
Rev. bras. farmacogn.. Publicado em: 27/05/2019
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11. UTILIZAÇÃO DA OCITOCINA EM GADO GIROLANDO: AVALIAÇÃO DA VIA VAGINAL COMO ALTERNATIVA À VIA ENDOVENOSA
Resumo O objetivo deste trabalho foi testar a viabilidade da utilização da via vaginal em fêmeas bovinas visando à aplicação de ocitocina a partir de formulações específicas. A ocitocina foi utilizada associada a facilitadores de absorção e na forma injetável (para comparação). Foram produzidas sete formulações, todas com concentração de 5
Ciênc. anim. bras.. Publicado em: 29/04/2019
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12. Determination of Gemifloxacin in human plasma by high performance liquid chromatography using Ultra Violet detector and its application to a bioequivalence study
A liquid chromatography method was developed and validated for the determination of gemifloxacin in human plasma using chloramphenicol as internal standard to achieve lower quantification limit. Acetonitrile was used to precipitated and extracted analyte and internal standard from plasma by Protein Precipitation. Analysis was performed isocratically on C18 c
Braz. J. Pharm. Sci.. Publicado em: 08/04/2019