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891.
Development and validation of a sensitive liquid chromatographic–tandem mass spectrometric method for the simultaneous analysis of granisetron and 7‐hydroxy granisetron in human plasma and urine samples: application in a clinical pharmacokinetic study in pregnant subject
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Yang Zhao Hui‐Jun Chen Steve Caritis Raman Venkataramanan 《Biomedical chromatography : BMC》2016,30(2):149-154
A liquid chromatography–tandem mass spectrometric method for the quantification of granisetron and its major metabolite, 7‐hydroxy granisetron in human plasma and urine samples was developed and validated. Respective stable isotopically labeled granisetron and 7‐hydroxy granisetron were used as internal standards (IS). Chromatography was performed using an Xselect HSS T3 analytical column with a mobile phase of 20% acetonitrile in water (containing 0.2 mM ammonium formate and 0.14% formic acid, pH 4) delivered in an isocratic mode. Tandem mass spectrometry operating in positive electrospray ionization mode with multiple reaction monitoring was used for quantification. The standard curves were linear in the concentration ranges of 0.5–100 ng/mL for granisetron and 0.1–100 ng/mL for 7‐hydroxy granisetron in human plasma samples, and 2–2000 ng/mL for granisetron and 2–1000 ng/mL for 7‐hydroxy granisetron in human urine samples, respectively. The accuracies were >85% and the precision as determined by the coefficient of variations was <10%. No significant matrix effects were observed for granisetron or 7‐hydroxy granisetron in either plasma or urine samples. Granisetron was stable under various storage and experimental conditions. This validated method was successfully applied to a pharmacokinetic study after intravenous administration of 1 mg granisetron to a pregnant subject. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
892.
Ian McNulty Barry Lai Jörg Maser David J. Paterson Paul Evans Steve M. Heald 《Synchrotron Radiation News》2013,26(4):34-42
In modern third generation synchrotron sources, undulators have become the principal source of X-rays and today a brilliance close to 1021 photons/sec?mm2?mrad?0.1%BW is routinely attained for photon energies of 10 keV. However, generating brilliant beams of photons with energies of 50 keV and above leads to conflicting choices for the undulator parameters as the following analysis shows. 相似文献
893.
894.
G. Leslie Burnett John C. Rohanna Steve Rosenberg Alfred K. Schultz Javier Read de Alaniz 《Journal of polymer science. Part A, Polymer chemistry》2016,54(13):1955-1960
We present the development of a method for the determination of methylene bridge crosslinking in 13C‐labeled chloromethylated polystyrene‐divinylbenzene resins. Our system uses a new room temperature reduction of the chloromethyl groups that circumvents the possible challenges associated with additional crosslinking. We demonstrate how the reduction of the chloromethyl groups allowed for the determination of methylene bridging, derived from the methylenebis(ethenylbenzene) crosslinker, based on the integration of the methylene signal in the 13C NMR spectra. Utilizing this method, the total crosslinking within the chloromethylated resin generated at 35 °C was determined to be upward of 10 wt %, which increased from 6 wt % in the unfunctionalized resin. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1955–1960 相似文献
895.
Steve Alpern Robbert Fokkink Christos Pelekis 《Journal of Optimization Theory and Applications》2012,153(3):650-661
Suppose that a hider possesses a continuously divisible resource that he may distribute around a circle. The resources on
a random arc in the circle are lost. The hider has a priori information on the length of the arc and he wants to maximize
the probability that the retrieved portion exceeds a critical quantity, which is enough to survive on. We show that there
exists an optimal resource distribution, which uses a finite number of point caches of equal size, establishing a conjecture of Kikuta and Ruckle. Our result is related to a conjecture of Samuels’ on-tail probabilities. 相似文献
896.
In situ xanthate deprotection to generate thiol chain transfer agents for conventional free radical linear and branched vinyl polymerization
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899.
Sunney I. Chan Steve S.-F. Yu Chih-Cheng Liu Chung-Yuan Mou 《Current Opinion in Green and Sustainable Chemistry》2020
Methanotrophs mediate the conversion of methane (CH4) into methanol selectively and efficiently near ambient conditions so we can learn from microbes to develop biomimetic catalysts capable of performing this difficult chemistry. This review highlights the development of a tricopper cluster catalyst that functions similar to the particulate methane monooxygenase enzyme in methanotrophic bacteria. The performance of this catalytic system formulated for quasi-heterogeneous catalysis is compared with other heterogeneous catalysts derived from Cu- and Fe-based zeolites and Cu mordenites known to activate CH4 stoichiometrically near 200 °C. We also highlight a unique catalytic system, in which the oxidizing power of both O atoms of the O2 molecule can be harnessed for oxidation of toluene to yield benzaldehyde at room temperature. 相似文献
900.
Benz[1,2-a]aceanthrylene is prepared from triptycene in 60 % yield by flash vacuum thermolysis at 875° C. 相似文献