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1.
Biomed Chromatogr ; 35(2): e4987, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32931605

RESUMO

The aim of this work was to develop and validate an analytical method using HPLC for the determination of propranolol in the different layers of the skin to be used in kinetic studies of skin permeation. The development of the method was based on the suitability of the chromatogram, and the validation followed the international health regulation for bioanalytical methods. In addition, the method was tested in an in vitro permeation assay using porcine skin. The drug was determined using an RP-C18 column at 30°C, a mobile phase comprising acidic aqueous phase:acetonitrile (75:25 v/v), at a flow rate of 1.0 mL min-1 , and UV detection at 290 nm. The method was demonstrated to be selective against skin contaminants, linear in a wide range of concentrations (3-20 µg mL-1 ), sensitive enough to quantify less than 0.1% of the drug dosage in skin matrices, and precise regardless of analysis variations such as day of analysis, analyst, or equipment. In addition, the method presented a high drug extraction capacity greater than 90% for all skin layers (stratum corneum, hair follicle, and remaining skin). Finally, the method was successfully tested in skin permeation assays, proving its value in the development of topical formulations containing propranolol.


Assuntos
Cromatografia de Fase Reversa/métodos , Propranolol/análise , Propranolol/farmacocinética , Pele/química , Animais , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Absorção Cutânea
2.
Talanta ; 183: 329-338, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29567183

RESUMO

We explored the use of carbon black (CB), graphene oxide (GO), copper nanoparticles (CuNPs) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) as electrode materials for the simultaneous determination of isoproterenol, acetaminophen, folic acid, propranolol and caffeine. The designed nanostructured surface was widely characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), contact angle measurements and electrochemistry. From electrochemical characterization assays carried out towards the potassium ferricyanide redox probe, fast electron transfer kinetics and a considerably higher electroactive surface area were observed for the modified electrodic surface based on CB, GO, CuNPs and PEDOT:PSS film. Using square-wave voltammetry (SWV), well defined and resolved anodic peaks were detected for isoproterenol, acetaminophen, folic acid, propranolol and caffeine, with peak-to-peak potential separation not less than 170 mV. Then, the SWV technique was explored for the simultaneous determination of quinary mixtures of these analytes, resulting in analytical curves with linear ranges and limits of detection at micromolar concentration levels. The practical viability of the proposed voltammetric sensor was illustrated in the analysis of human body fluid samples. The proposed sensor showed good repeatability and a successful application using urine and serum matrices, with recoveries close to 100%.


Assuntos
Acetaminofen/análise , Cafeína/análise , Ácido Fólico/análise , Isoproterenol/análise , Propranolol/análise , Compostos Bicíclicos Heterocíclicos com Pontes/química , Cobre/química , Grafite/química , Nanopartículas Metálicas/química , Estrutura Molecular , Óxidos/química , Tamanho da Partícula , Polímeros/química , Poliestirenos/química , Fuligem/química
3.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484528

RESUMO

Previous works had shown that scorpion venom induced neurotransmitter elevation and an inflammatory response associated with various anatomo-pathological modifications. The most dangerous scorpions species in Algeria responsible for these effects are Androctonus australis hector(Aah) and Androctonus amoreuxi (Aam). Results Comparison of the physiopathological effects induced by the two venoms showed differences in the kinetic of cytokine release and in lung injury. The lung edema was only observed in response to Aah venom and it was correlated with cell infiltration. In order to better understand the involved mechanism in inflammatory response, we used two antagonists, atropine (non-selective muscarinic antagonist) and propranolol (β adrenergic antagonist), which lead to a decrease of cell infiltration but has no effect on edema forming.Conclusion These results suggest another pathway in the development of lung injury following envenomation with Aam or Aah venom.


Assuntos
Animais , Atropina/análise , Citocinas/biossíntese , Propranolol/análise , Venenos de Escorpião/análise , Escorpiões/classificação
4.
Sci Total Environ ; 452-453: 137-47, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23500407

RESUMO

This study investigated the degradation of atenolol, metoprolol and propranolol beta-blockers by ferrate (K2FeO4) in hospital wastewater and in aqueous solution. In the case of hospital wastewater, the effect of the independent variables pH and [Fe(VI)] was evaluated by means of response surface methodology. The results showed that Fe(VI) plays an important role in the oxidation-coagulation process, and the treatment of the hospital wastewater led to degradations above 90% for all the three ß-blockers, and to reductions of aromaticity that were close to 60%. In addition, only 17% of the organic load was removed. In aqueous solution, the degradation of the ß-blockers atenolol, metoprolol and propranolol was 71.7%, 24.7% and 96.5%, respectively, when a ratio of 1:10 [ß-blocker]:[Fe(VI)] was used. No mineralization was achieved, which suggests that there was a conversion of the ß-blockers to degradation products identified by liquid chromatography/mass spectrometry tandem. Degradation pathways were proposed, which took account of the role of Fe(VI). Furthermore, the ready biodegradability of the post-process samples was evaluated by using the closed bottle test, and showed an increase in biodegradability. The use of the ferrate advanced oxidation technology seems to be a useful means of ensuring the remediation of hospital and similar wastewater.


Assuntos
Antagonistas Adrenérgicos beta/química , Biodegradação Ambiental , Ferro/química , Poluentes Químicos da Água/química , Antagonistas Adrenérgicos beta/análise , Atenolol/química , Cromatografia Líquida/métodos , Interpretação Estatística de Dados , Hospitais , Espectrometria de Massas/métodos , Resíduos de Serviços de Saúde , Eliminação de Resíduos de Serviços de Saúde/métodos , Metoprolol/análise , Metoprolol/química , Modelos Teóricos , Oxirredução , Propranolol/análise , Propranolol/química , Poluentes Químicos da Água/análise
5.
Artigo em Inglês | VETINDEX | ID: vti-9292

RESUMO

Previous works had shown that scorpion venom induced neurotransmitter elevation and an inflammatory response associated with various anatomo-pathological modifications. The most dangerous scorpions species in Algeria responsible for these effects are Androctonus australis hector(Aah) and Androctonus amoreuxi (Aam). Results Comparison of the physiopathological effects induced by the two venoms showed differences in the kinetic of cytokine release and in lung injury. The lung edema was only observed in response to Aah venom and it was correlated with cell infiltration. In order to better understand the involved mechanism in inflammatory response, we used two antagonists, atropine (non-selective muscarinic antagonist) and propranolol (β adrenergic antagonist), which lead to a decrease of cell infiltration but has no effect on edema forming.Conclusion These results suggest another pathway in the development of lung injury following envenomation with Aam or Aah venom.(AU)


Assuntos
Animais , Venenos de Escorpião/análise , Atropina/análise , Propranolol/análise , Citocinas/biossíntese , Escorpiões/classificação
6.
Electrophoresis ; 30(22): 3910-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19876961

RESUMO

A CE method is described for the enantioselective analysis of propranolol (Prop) and 4-hydroxypropranolol (4-OH-Prop) in liquid Czapek medium with application in the study of the enantioselective biotransformation of Prop by endophytic fungi. The electrophoretic conditions previously optimized were as follows: an uncoated fused-silica capillary, 4% w/v carboxymethyl-beta-CD in 25 mmol/L triethylamine/phosphoric acid (H(3)PO(4)) buffer at pH 9 as running electrolyte and 17 kV of voltage. UV detection was carried out at 208 nm. Liquid-liquid extraction using diethyl ether: ethyl acetate (1:1 v/v) as extractor solvent was employed for sample preparation. The calibration curves were linear over the concentration range of 0.25-10.0 microg/mL for each 4-OH-Prop enantiomer and 0.10-10.0 microg/mL for each Prop enantiomer (r>or=0.995). Within-day and between-day relative standard deviations and relative errors for precision and accuracy were lower than 15% for all the enantiomers. Finally, the validated method was used to evaluate Prop biotransformation in its mammalian metabolite 4-OH-Prop by some selected endophytic fungi. The screening of five strains of endophytic fungi was performed and all of them could biotransform Prop to some extent. Specifically, Glomerella cingulata (VA1) biotransformed 47.8% of (-)-(S)-Prop to (-)-(S)-4-OH-Prop with no formation of (+)-(R)-4-OH-Prop in 72 h of incubation.


Assuntos
Eletroforese Capilar/métodos , Propranolol/análogos & derivados , Propranolol/análise , Aspergillus fumigatus/metabolismo , Asteraceae/microbiologia , Biotransformação , Chaetomium/metabolismo , Limite de Detecção , Penicillium/metabolismo , Phyllachorales/metabolismo , Propranolol/metabolismo , Estereoisomerismo
7.
Anal Chim Acta ; 651(1): 31-5, 2009 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-19733731

RESUMO

The determination of propranolol enantiomers in human plasma and urine by spectrofluorimetry and a second-order standard addition method is described. The methodology is based on chiral recognition of propranolol by formation of an inclusion complex with beta-cyclodextrin, a chiral auxiliary, in the presence of 1-butanol. The adopted strategy combines the use of PARAFAC, for extraction of the pure analyte signal, with the standard addition method, for determinations in the presence of an individual matrix effect caused by the quenching action of the proteins present in the plasma and urine. A specific PARAFAC model was built for each sample, in triplicate, and the scores were related to (R)-propranolol mole fraction using a linear regression in the standard addition method. Using a propranolol with concentration of 260 ng mL(-1), good results were obtained for determinations in the mole fraction range from 50 to 80% of (R)-propranolol, providing absolute errors between 0.4 and 3.6% for plasma and between 0.9 and 6.0% for urine.


Assuntos
Adrenérgicos/análise , Propranolol/análise , Espectrometria de Fluorescência/métodos , 1-Butanol/química , Adrenérgicos/sangue , Adrenérgicos/urina , Humanos , Propranolol/sangue , Propranolol/urina , Espectrometria de Fluorescência/normas , Estereoisomerismo , beta-Ciclodextrinas/química
8.
J Chromatogr A ; 1216(45): 7957-61, 2009 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-19782368

RESUMO

The aim of this study was to develop a fast capillary electrophoresis method for the determination of propranolol in pharmaceutical preparations. In the method development the pH and constituents of the background electrolyte were selected using the effective mobility versus pH curves. Benzylamine was used as the internal standard. The background electrolyte was composed of 60mmolL(-1) tris(hydroxymethyl)aminomethane and 30mmolL(-1) 2-hydroxyisobutyric acid, at pH 8.1. Separation was conducted in a fused-silica capillary (32cm total length and 8.5cm effective length, 50microm I.D.) with a short-end injection configuration and direct UV detection at 214nm. The run time was only 14s. Three different strategies were studied in order to develop a fast CE method with low total analysis time for propranolol analysis: low flush time (Lflush) 35runs/h, without flush (Wflush) 52runs/h, and Invert (switched polarity) 45runs/h. Since the three strategies developed are statistically equivalent, Wflush was selected due to the higher analytical frequency in comparison with the other methods. A few figures of merit of the proposed method include: good linearity (R(2)>0.9999); limit of detection of 0.5mgL(-1); inter-day precision better than 1.03% (n=9) and recovery in the range of 95.1-104.5%.


Assuntos
Antagonistas Adrenérgicos beta/análise , Eletroforese Capilar/métodos , Preparações Farmacêuticas/análise , Propranolol/análise , Limite de Detecção , Fatores de Tempo
9.
Electrophoresis ; 30(16): 2874-81, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19691051

RESUMO

An experimental design optimization (Box-Behnken design, BBD) was used to develop a CE method for the simultaneous resolution of propranolol (Prop) and 4-hydroxypropranolol enantiomers and acetaminophen (internal standard). The method was optimized using an uncoated fused silica capillary, carboxymethyl-beta-cyclodextrin (CM-beta-CD) as chiral selector and triethylamine/phosphoric acid buffer in alkaline conditions. A BBD for four factors was selected to observe the effects of buffer electrolyte concentration, pH, CM-beta-CD concentration and voltage on separation responses. Each factor was studied at three levels: high, central and low, and three center points were added. The buffer electrolyte concentration ranged from 25 to 75 mM, the pH ranged from 8 to 9, the CM-beta-CD concentration ranged from 3.5 to 4.5% w/v, and the applied run voltage ranged from 14 to 20 kV. The responses evaluated were resolution and migration time for the last peak. The obtained responses were processed by Minitab to evaluate the significance of the effects and to find the optimum analysis conditions. The best results were obtained using 4% w/v CM-beta-CD in 25 mM triethylamine/H3PO4 buffer at pH 9 as running electrolyte and 17 kV of voltage. Resolution values of 1.98 and 1.95 were obtained for Prop and 4-hydroxypropranolol enantiomers, respectively. The total analysis time was around of 15 min. The BBD showed to be an adequate design for the development of a CE method, resulting in a rapid and efficient optimization of the pH and concentration of the buffer, cyclodextrin concentration and applied voltage.


Assuntos
Eletroforese Capilar/métodos , Propranolol/análogos & derivados , Propranolol/análise , Concentração de Íons de Hidrogênio , Análise de Regressão , Estereoisomerismo , beta-Ciclodextrinas/química
10.
Anal Chim Acta ; 623(1): 38-45, 2008 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-18611455

RESUMO

The quantification of mixtures of (R)- and (S)-propranolol (PRO) in the pure form and in the pharmaceutical preparations is described. The methodology is based on chiral recognition of propranolol by formation of an inclusion complex with beta-cyclodextrin (CD), a chiral auxiliary, in the presence of 1-butanol. The excitation-emission fluorescence surface and second-order multivariate calibration such as bilinear least squares (BLLS) and parallel factor analysis (PARAFAC) were used in the model development. BLLS performed better than PARAFAC, presenting relative mean error in the order of 3.5%, analytical sensitivity of 0.07% and 0.08%, detection limit of 0.23% and 0.28% and quantification limit of 0.71% and 0.84% for the pure form and pharmaceutical preparations, respectively. These results indicate that the proposed methodology can be an alternative for the determination of propranolol enantiomeric composition.


Assuntos
Fluorescência , Propranolol/análise , Propranolol/química , 1-Butanol/química , Calibragem , Análise dos Mínimos Quadrados , Modelos Lineares , Preparações Farmacêuticas/química , Padrões de Referência , Estereoisomerismo , beta-Ciclodextrinas/química
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