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991.
Determination of mazindol in human oral fluid by high performance liquid chromatography–electrospray ionization mass spectrometry 下载免费PDF全文
Marcella Herbstrith de Oliveira Graciela Carlos Ana Maria Bergold Flavio Pechansky Renata Pereira Limberger Pedro Eduardo Fröehlich 《Biomedical chromatography : BMC》2014,28(8):1064-1069
Brazil is one of the countries most affected by abuse of stimulant medications by professional drivers, especially fenproporex, amfepramone and mazindol. Even though their sale is banned, they can be found in illegal markets, such as those located on the country's borders. The use of oral fluid to monitor drug levels has many advantages over plasma and urine because it is noninvasive, easier to collect and more difficult to adulterate. The aim of this study was to develop and validate a sensitive and specific method to quantify mazindol in human oral fluid by liquid chromatography–mass spectrometry (LC‐MS). The LC system consisted of an LC‐MS system operated in selected ion monitoring mode. The mobile phase was composed of water at pH 4.0, acetonitrile and methanol (60:15:25 v/v/v) at a flow rate of 1.0 mL/min and propranolol was used as internal standard. Total running time was 10 min. The lower limit of quantification was 0.2 ng/mL and the method exhibited good linearity within the 0.2–20 ng/mL range (r = 0.9987). A rapid, specific, sensitive, linear, precise and accurate method was developed for determination of mazindol in human oral fluid according to European Medicines Agency guidelines, and is suitable for monitoring mazindol levels in oral fluid of professional drivers. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
992.
In this work, we report a sol?Cgel route to fabricate oxide nanowires of BiFeO3 using two-step anodic aluminum oxide as template. We prepared oxide nanowires with uniform dimensions that can vary from 35 to 100?nm in diameter and with 4???m in length, as confirmed by scanning electron microscopy and transmission electron microscopy measurements. Magnetization measurements, performed in a vibrating sample magnetometer, show that this nanostructures present ferromagnetism at room temperature. 相似文献
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Maria Jo?o Carrilho Plancha Carmen Mireya Rangel César Augusto Correia de Sequeira 《Journal of Solid State Electrochemistry》2012,16(2):665-671
The (PEO)4ZnCl2 electrolyte (PEO, polyethylene oxide) was studied in view of its potential application in a solid-state rechargeable zinc
cell. The electrochemical stability window was established, and decomposition voltage values between 3.19 (20 °C) and 1.44 V
(150 °C) were estimated. Cyclic voltammetry studies using a Pt/(PEO)4ZnCl2/Pt cell indicated reversibility of the Zn2+/Zn couple at the electrode/electrolyte interface. Laboratory cells Zn(−)/(PEO)4ZnCl2/Nb2O5(+) were assembled and studied at 55 °C, under various discharge current densities. Results of cell discharge profiles, capacity
values, charge–discharge cycles and cell stabilities are reported. 相似文献
995.
Rosário Monteiro Gil Faria Manuela Meireles Luísa Correia‐Sá Diana Teixeira Ana Faria Conceição Calhau Valentina F. Domingues Cristina Delerue‐Matos 《Biomedical chromatography : BMC》2012,26(12):1494-1501
Scientific evidence has shown an association between organochlorine compounds (OCC) exposure and human health hazards. Concerning this, OCC detection in human adipose samples has to be considered a public health priority. This study evaluated the efficacy of various solid‐phase extraction (SPE) and cleanup methods for OCC determination in human adipose tissue. Octadecylsilyl endcapped (C18‐E), benzenesulfonic acid modified silica cation exchanger (SA), poly(styrene‐divinylbenzene (EN) and EN/RP18 SPE sorbents were evaluated. The relative sample cleanup provided by these SPE columns was evaluated using gas chromatography with electron capture detection (GC–ECD). The C18‐E columns with strong homogenization were found to provide the most effective cleanup, removing the greatest amount of interfering substance, and simultaneously ensuring good analyte recoveries higher than 70%. Recoveries > 70% with standard deviations (SD) < 15% were obtained for all compounds under the selected conditions. Method detection limits were in the 0.003–0.009 mg/kg range. The positive samples were confirmed by gas chromatography coupled with tandem mass spectrometry (GC‐MS/MS). The highest percentage found of the OCC in real samples corresponded to HCB, o,p′‐DDT and methoxychlor, which were detected in 80 and 95% of samples analyzed respectively. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Nera Cagnoli Paolo Ceccherelli Massimo Curini Maria Carla Marcotullio Ernest Wenkert 《合成通讯》2013,43(11):1261-1271
Copper oxide-catalyzed decomposition of 1-diazoacetyl-1-methyl-3-methylenecyclohexanes produces strained tricycles whose reduction or hydrolysis affords 6-bicyclo[3.2.1]octanones. 相似文献
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The synthesis of (±)10H-phenothiazine-10-propanoyl-1′-myo-inositol was accomplished in order to test it as inhibitor of phosphatidylinositol specfic phospholipase C (PI-PLC). 相似文献