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991.
Isolation and purification of monosialotetrahexosylgangliosides from pig brain by extraction and liquid chromatography 下载免费PDF全文
Monosialotetrahexosylganglioside (GM1), one of glycosphingolipids containing sialic acid, plays particularly important role in fighting against paralysis, dementia and other diseases caused by brain and nerve damage. In this work, a simple and highly efficient method with high yield was developed for isolation and purification of GM1 from pig brain. The method consisted of an extraction by chloroform–methanol–water and a two‐step chromatographic separation by DEAE–Sepharose Fast Flow anion‐exchange medium and Sephacryl S‐100 HR size‐exclusion medium. The purified GM1 was proved to be homogeneous and had a purity of >98.0% by high‐performance anion‐exchange and size‐exclusion chromatography. The molecular weight was 30.0 kDa by high‐performance size‐exclusion chromatography and 1546.9 Da by electrospray ionization mass spectrometry. The chromogenic reaction by resorcinol–hydrochloric acid solution indicated that the purified GM1 showed a specific chromogenic reaction of sialic acid. Through this isolation and purification program, ~1.0 mg of pure GM1 could be captured from 500 g wet pig brain tissue and the yield of GM1 was around 0.022%, which was higher than the yields by other methods. The method may provide an alternative for isolation and purification of GM1 in other biological tissues. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Li+/Mg2+ Hybrid‐Ion Batteries with Long Cycle Life and High Rate Capability Employing MoS2 Nano Flowers as the Cathode Material 下载免费PDF全文
Yanming Ju Yuan Meng Prof. Yingjin Wei Xiaofei Bian Qiang Pang Dr. Yu Gao Prof. Fei Du Prof. Bingbing Liu Prof. Gang Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):18073-18079
The demand for large‐scale and safe energy storage is increasing rapidly due to the strong push for smartphones and electric vehicles. As a result, Li+/Mg2+ hybrid‐ion batteries (LMIBs) combining a dendrite‐free deposition of Mg anode and Li+ intercalation cathode have attracted considerable attention. Here, a LMIB with hydrothermal‐prepared MoS2 nano flowers as cathode material was prepared. The battery showed remarkable electrochemical properties with a large discharge capacity (243 mAh g?1 at the 0.1 C rate), excellent rate capability (108 mAh g?1 at the 5 C rate), and long cycle life (87.2 % capacity retention after 2300 cycles). Electrochemical analysis showed that the reactions occurring in the battery cell involved Mg stripping/plating at the anode side and Li+ intercalation at the cathode side with a small contribution from Mg2+ adsorption. The excellent electrochemical performance and extremely safe cell system show promise for its use in practical applications. 相似文献
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Study on the interaction of plasma protein binding rate between edaravone and taurine in human plasma based on HPLC analysis coupled with ultrafiltration technique 下载免费PDF全文
Dao‐quan Tang Yin‐jie Li Zheng Li Ting‐ting Bian Kai Chen Xiao‐xiao Zheng Yan‐yan Yu Shui‐shi Jiang 《Biomedical chromatography : BMC》2015,29(8):1137-1145
In this work, two high‐performance liquid chromatography (HPLC) assays were developed and validated for the independent determination of edaravone and taurine using 3‐methyl‐1‐p‐tolyl‐5‐pyrazolone and L ‐glutamine as internal standards. In in vitro experiments, human plasma was separately spiked with a mixture of edaravone and taurine, edaravone or taurine alone. Plasma was precipitated with acetonitrile containing 0.1% formic acid. Ultrafiltration was employed to obtain the unbound ingredients of the two drugs. The factors that might influence the ultrafiltration effiency were elaborately optimized. Plasma supernatant and ultrafiltrate containing taurine were derivated with o‐phthalaldehyde and ethanethiol in the presence of 40 mmol/L sodium borate buffer (pH 10.2) at room temperature within 1 min. Chromatographic separations were achieved on an InertSustain C18 column (250 × 4.6 mm, 5 µm). Isocratic 50 mmol/L ammonium acetate–acetonitrile and gradient 50 mmol/L sodium acetate (pH 5.3)–methanol were respectively selected as the mobile phase for the determination of edaravone and taurine. All of the validation data including linearity, extraction recovery, precision, accuracy and stability conformed to the requirements. Results showed that there were no significant alterations in the plasma protein binding rate of taurine and edaravone, implying that the proposed combination therapy was pharmacologically feasible. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Comparative metabolism of four limonoids in human liver microsomes using ultra‐high‐performance liquid chromatography coupled with high‐resolution LTQ‐Orbitrap mass spectrometry 下载免费PDF全文
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Xianhua Wang Feng Chen Qing Yang Hewei Liu Hao Bian Jinhai Si Xun Hou 《Applied Physics A: Materials Science & Processing》2011,102(1):39-44
We demonstrate that quasi-periodic void structure can be self-formed in transparent materials by single femtosecond laser
pulse. Compared to the multiple-pulse induced structures, the single-pulse induced void structures are very short and may
contain absent voids. The formation mechanisms have been discussed comparatively in detail. Based on this, a technique for
high-speed and large-area fabrication of micro-void arrays in transparent materials has been presented. The experimental results
show that 3D micro-void structures which contain over several hundred thousand voids in micrometer scales are produced in
areas of square millimeters within a few minutes, and the periods of micro-void structures can be easily varied by processing
parameters. This work has potential applications in 3D optical storage, photonic crystal and integrated optics, and provides
novel insight into the interaction between the single femtosecond pulse and the transparent materials. 相似文献