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991.
Determination of fexofenadine in Hank's balanced salt solution by high‐performance liquid chromatography with ultraviolet detection: application to Caco‐2 cell permeability studies 下载免费PDF全文
Marco Antônio dos. Reis Júnior Ana Cláudia Miranda de Faria Eudes da. Silva Velozo Teresa Dalla Costa Frank Pereira de Andrade Whocely Victor de Castro 《Biomedical chromatography : BMC》2015,29(4):537-544
The drug‐transporting proteins can affect the pharmacokinetics and pharmacodymanics of many drugs, resulting in an erratic and unpredictable pharmacological response. The Caco‐2 monolayer is routinely applied to investigate the carrier‐mediated transport of drugs. Therefore, the selection of a marker compound able to characterize the activity of such transporters is crucial. Fexofenadine (FEX), a P‐gp/OATP substrate, can be considered a suitable probe. However, in order to use be used as a marker compound, it is mandatory to develop an analytical method able to quantify this drug during the in vitro permeability assay. An HPLC method with ultraviolet detection was developed; the mobile phase consisted of phosphate buffer (pH 3.2) containing 10 m m of sodium octanosulphonate and acetonitrile (60:40) and the flow rate was set at 1.2 mL/min. Fexofenadine was eluted at 40°C, the retention time was about 4.6 min. The LOD and LOQ values were 1.9 and 6.2 ng/mL, respectively. Verapamil and ketoconazole, the most common P‐gp inhibitors, were eluted as distinct peaks of that corresponding to fexofenadine The method was successfully applied to quantify the amount of FEX transported across the Caco‐2 monolayer and could be an additional tool for those investigating the role of membrane transporters on drug absorption. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
992.
A theoretical and experimental study of the NMR spectra of 4,5,6,7‐tetrafluorobenzazoles with special stress on PCM calculations of chemical shifts 下载免费PDF全文
Ibon Alkorta José Elguero Marta Pérez‐Torralba Concepción López Rosa M. Claramunt 《Magnetic resonance in chemistry : MRC》2015,53(5):353-362
The chemical shifts and several 19F–19F, 13C–19F and 1H–19F spin‐spin coupling constants (SSCSs) of eight 4,5,6,7‐tetraflurobenzazoles (three benzimidazoles, three benzimidazolinones and two indazoles) have been determined. The chemical shifts were discussed using gauge including atomic orbital‐density functional theory calculations taking into account solvent effects (polarizable continuum model) and, for the solid state, hydrogen bonds (clusters up to three molecules). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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do Nascimento Marreiro Teixeira Ana Siqueira Siqueira Teixeira Paulo Ronaldo Sousa de Oliveira Farias Emanuel Airton Ferraz e Sousa Brandon Moura Sérvulo Kátia Bonfim de Leite da Silva Durcilene Alves Eiras Carla 《Journal of Solid State Electrochemistry》2020,24(5):1143-1155
Journal of Solid State Electrochemistry - The present work proposes a new electrochemical sulfite biosensor based on babassu mesocarp nanoparticles (BMNPs) immobilized on the surface of a pyrolytic... 相似文献
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