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901.
Feng Qiu Shujun Fu Shujun Zhou Shihai Yang Meihua Yang 《Biomedical chromatography : BMC》2013,27(2):233-239
This study firstly describes the development of an accurate and sensitive high‐performance liquid chromatography–tandem mass spectrometry (LC‐MS/MS) assay for the quantification of Taiwanin E methyl ether (TEME) in rat plasma. The assay involved a simple liquid–liquid extraction step with ethyl acetate and a gradient elution using a mobile phase consisting of water containing 0.1% formic acid and acetonitrile containing 0.1% formic acid. Chromatographic separation was successfully achieved on an Agilent Zorbax‐C18 column (2.1 × 50 mm, 3.5 µm) with a flow rate of 0.40 mL/min. The multiple reaction monitoring was based on the transitions of m/z = 379.1 → 320.1 for TEME and 386.1 → 122.0 for buspirone (internal standard). The assay was validated to demonstrate the specificity, linearity, recovery, accuracy, precision and stability. The lower limit of quantification was 0.50 ng/mL in 50 μL of rat plasma. The developed and validated method was successfully applied to the quantification and pharmacokinetic study of TEME in rats after intravenous and oral administration of 1.45 mg/kg TEME. The oral absolute bioavailability of TEME was estimated to be 5.85 ± 1.41% with an elimination half‐life value of 2.61 ± 0.55 h, suggesting its poor absorption and/or strong metabolism in vivo. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
902.
Zhou Yan Bing Xia Ming Hua Qiu Ding Li Sheng Hong Xi Xu 《Biomedical chromatography : BMC》2013,27(11):1560-1567
A rapid and reliable method was established for simultaneous determination of main triterpenoids in Ganoderma lucidum spores using ultra‐high‐performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC‐TQ‐MS). The established method was validated in terms of linearity, sensitivity, precision, accuracy and stability, and was successfully applied to determine the contents of 10 main triterpenoids in different batches of G. lucidum spores. The analysis results showed that moderate levels of triterpenoids were found in G. lucidum spores. In addition, a MS full scan with a daughter ion scan experiment was performed to identify the potential derivatives of triterpenoids present in G. lucidum spores. As a result, a total of 22 triterpenoids from different G. lucidum spores were unequivocally or tentatively identified via comparisons with authentic standards and literatures. This method provides both qualitative and quantitative results without the need for repetitive UPLC‐MS analyses, thereby increasing efficiency and productivity, making it suitable for high‐throughput applications. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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904.
As the hardware of FLIM technique becomes mature, the most important criterion for FLIM application is the correct interpretation of its data. In this research, first of all, a more orthogonal phasor approach, called as Modified Phasor Approach (MPA), is put forward. It is a way to calculate the lifetime of the complex fluorescent process, and a rule to measure how much the fluorescence process deviates from single exponential decay. Secondly, MPA is used to analysis the time-resolved fluorescence processes of the transfected CHO-K1 Cell lines expressing adenosine receptor A1R tagged by CYP and YFP, measured in the channel of the acceptor. The image of the fluorescence lifetime and the multiplication of the fluorescence lifetime and deviation from single exponential decay reveal the details of the Homo-FRET. In one word, MPA provides the physical meaning in its whole modified phasor space, and broadens the way for the application of the fluorescence lifetime imaging. 相似文献
905.
A new metal complex[MnL2](NO3)2·CH3CN(1) was synthesized by reaction of 4’-4-(l,2,4-triazol-l-yl)phenyl -2,2’:6’,2"-terpyridine(L) with manganese nitrate.The structure of the complex was determined by X-ray crystallography.The results of UV-vis studies showed that the complex exhibits colorimetric sensing ability for Fe3+,which can be observed by naked eye. 相似文献
906.
Methyl carbamates, prepared by reacting primary and secondary amines with chlorocarbonate, react smoothly with sodium hydrogen telluride in DMF and regenerate the amines in moderate yields. 相似文献
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910.
Hai-Kun Zhang Hong Lu Jing Wang Guang-Fei Liu Ji-Ti Zhou 《Applied biochemistry and biotechnology》2014,174(2):602-611
In this study, the effects of bio-reduced graphene oxide (BRGO) on the bio-reduction of Acid Red 18 (AR 18) by Shewanella algae were first investigated, and a possible mechanism of BRGO-mediated AR 18 bio-decolorization was proposed. The prepared BRGO was characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffractometer (XRD), infrared spectroscopy (IR), Raman spectra, and transmission electron microscope (TEM), respectively. Moreover, electrochemical experiment demonstrated that BRGO is of good electrical conductivity. AR 18 bio-decolorization could be enhanced in dose-dependent manner of BRGO. The maximum increase in AR 18 removal efficiency was observed at a dose of 0.075 g L?1 BRGO. Under the same conditions, BRGO could also improve the decolorization rates of Acid Red 88, Acid Red 27, and Acid Red 73. During decolorization, the formation of BRGO and cells composite was observed, which is beneficial for transferring electrons from cells to BRGO. In addition, BRGO could accelerate the bio-decolorization of AR 18 under saline conditions (2–7 %). These findings indicate that BRGO can accelerate the electrons transfer from cells to azo dyes. 相似文献