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951.
A simple,rapid and reliable liquid chromatography–mass spectrometry method for determination of methotrexate in human plasma and its application to therapeutic drug monitoring
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Dan Wu Yixuan Wang Yan Sun Nian Ouyang Jun Qian 《Biomedical chromatography : BMC》2015,29(8):1197-1202
A simple, rapid and reliable liquid chromatography–electrospray ionization tandem mass spectrometry method was established and validated for the determination of methotrexate in human plasma. After a straightforward protein precipitation by acetonitrile–water (70:30, v/v), methotrexate (MTX) and p‐aminoacetophenone (used as internal standard, IS) were separated on a Column C18 column (50 × 2.1 mm, 3 µm; Column Technology, Fremont, CA, USA) using a gradient elution with mobile phase of acetonitrile and 0.03% acetic acid aqueous solution at a flow rate of 0.5 mL/min. The total chromatographic runtime was 5 min for each injection. Quantification detection was performed in a triple‐quadruple tandem mass spectrometer under positive mode monitoring the following mass transitions: m/z 455.3 → 308.3 for MTX and m/z 136.1 → 94.4 for IS. The calibration curve was linear over the range of 0.05–25.0 µmol/L with a lower limit of quantification of 0.05 µmol/L. The intra‐ and interday precisions were <5.2%, the accuracy varied from ?4.1 to 4.5%. The recovery was >94%. The LC‐MS/MS method showed an excellent agreement with the existing HPLC‐UV method using Passing–Bablok regression and Bland–Altman difference plot analysis. The validated LC‐MS/MS can be successfully applied to the routine therapeutic drug monitoring of MTX in clinical laboratories. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
952.
953.
Abduraouf Alamer Mohamed Abdurhman Yan Zhang Guoan Zhang Shuai Wang 《Analytical and bioanalytical chemistry》2015,407(26):8129-8136
954.
955.
Hengfeng Fan Huafeng Zhou Chaolong Ma Yiqing Huang Yan Li 《Molecular Crystals and Liquid Crystals》2014,593(1):232-242
The effect of humidity on the holographic grating diffraction efficiency and transmittance kinetics in the E204Q BR gelatin film is investigated. We found a correlation between the accumulation of the red-light absorbing O intermediate in the later part of the E204Q BR photocycle and sharpness (decay to the steady-state) of the holographic recording kinetics. As shown, at humidity exceeding 95% the ratio between the peak and steady-state of the diffraction efficiency for the weak probe beam (670 nm) can reach 8.7 in the E204Q BR film, which is sufficient for realization of an efficient novelty filter. 相似文献
956.
Cover Picture: Ultrathin Coating of Confined Pt Nanocatalysts by Atomic Layer Deposition for Enhanced Catalytic Performance in Hydrogenation Reactions (Chem. Eur. J. 25/2016)
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957.
958.
Optical Review - To solve the problems of long transmission delay and high energy consumption caused by the number of optical communication signals and sub-nodes in the network, a deep fusion... 相似文献
959.
Serum pharmacochemistry combined with multiple data processing approach to screen the bioactive components and their metabolites in Mutan Cortex by ultra‐performance liquid chromatography tandem mass spectrometry
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Jian‐hua Liu Hui Sun Ai‐hua Zhang Guang‐li Yan Ying Han Chang‐song Xue Xiao‐hang Zhou Hui Shi Xi‐jun Wang 《Biomedical chromatography : BMC》2014,28(4):500-510
Root cortex of Paeonia suffruticosa Andrews (Paeoniaceae), known as Moutan Cortex (MC), is known to have anti‐allergic and anti‐inflammatory properties. However, the constituents absorbed into blood after oral administration of MC remain unknown. A sensitive and rapid method by ultra‐high‐pressure liquid chromatography–electrospray ionization–quadrupole‐time‐of‐flight mass spectrometry (UPLC‐ESI‐Q‐TOF‐MS) technology and the MetaboLynxTM software combined with multiple data processing approach (Mdpa) was established to investigate the absorbed constituents in rats after oral administration of MC, providing unique high‐throughput capabilities for drug metabolism study. A hyphenated electrospray ionization and quadrupole‐time‐of‐flight analyzer was used for the determination of accurate mass of the fragment ion in negative mode, with excellent MS mass accuracy and enhanced data acquisition. This rapid automated analysis method was successfully applied for screening and identification of the constituents absorbed and metabolized studies of MC after oral administration to rats. A total of 46 peaks were obtained from MC, 41 of which were tentatively characterized. In the VIP‐plot of orthogonal partial least‐squares discriminant analysis, 23 interesting ions in serum samples were extracted, and 16 parent components and seven metabolites were detected in vivo. The integrative serum pharmacochemistry technique, UPLC‐ESI‐Q‐TOF‐MS, and Mdpa method were successfully applied for rapid discovery of multiple components from MC. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
960.
Bingyan Jiang Lei Zhang Jie Yan Qingquan Huang Bing Liao Hao Pang 《Journal of polymer science. Part A, Polymer chemistry》2014,52(17):2442-2453
A series of well‐defined thermoresponsive graft polymers with different lengths and graft densities, poly(glycidyl methacrylate)‐graft‐poly(N‐isopropylacrylate) (PGMA‐g‐PNIPAM), were successfully prepared by combination of controlled/living free radical polymerization and click chemistry. Effects of grafting length and density on the thermoresponsive behavior, aggregating mean diameter, and self‐assembly morphology are systematically investigated. The thermosensitive characteristics of graft polymers in aqueous solution prove that the length and graft density had positive co‐relationship with the lower critical solution temperature value and mean diameter of micelles as well as the size distribution, while the effect of graft length of polymers is more significant than that of density. Transmission electron microscopy analysis shows that the conformations of PGMA45‐g‐PNIPAM20 and PGMA45‐g‐PNIPAM46 with longer length and bigger grafting density in aqueous solutions are spherical nanoparticles with the increasing trend of the diameters, while that of PGMA45‐g‐PNIPAM(73, 50%) shows a spherical‐like morphology, which indicates that the graft length and density have a significant effect on the mean diameter of micelle but not on the self‐assembly morphology. These results reveal that to obtain desired thermoresponsive behavior and self‐assembly morphology of functional polymers, it is essential to design and fabricate the structure of graft polymers with proper length and graft density. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2442–2453 相似文献