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Zhi‐Yong Guo Pan‐Pan Gai Jing Duan Jin‐Xia Zhai Sha‐Sha Zhao Sui Wang Dan‐Yi Wei 《Biomedical chromatography : BMC》2010,24(10):1094-1099
A gas chromatography–mass spectrometry assay was developed and validated for the simultaneous determination of phthalates and adipates in human serum. The phthalates and adipates studied were dimethyl phthalate, diethyl phthalate, dibutyl phthalate, benzylbutyl phthalate, di‐2‐ethylhexyl phthalate, di‐n‐octyl phthalate, diethyl adipate, dibutyl adipate, diisobutyl adipate, bis(2‐butoxyethyl) adipate and di‐2‐ethylhexyl adipate, with diisooctyl phthalate as internal standard. The extraction and cleaning up procedure was carried out with solid‐phase extraction cartridges containing dimethyl butylamine groups, which showed extraction efficiencies over 88% for each analyte and the internal standard. The calibration curves obtained were linear with correlation coefficients greater than 0.98. For all analytes, the assay gave CV% values for intra‐day precision from 4.9 to 13.3% and mean accuracy values from 91.4 to 108.4%, while inter‐day precision was 5.2–13.4% and mean accuracy 91.0–110.2%. The limits of detection for the assay of phthalates and adipates were in the range 0.7–4.5 ng/mL. The method is simple, sensitive and accurate, and allows for simultaneous determination of nanogram levels of phthalates and adipates in human serum. It was successfully applied to an investigation on the level of phthalates and adipates in a non‐occupationally exposed population. 相似文献
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Yi‐Hong Tang Guang‐Xin Xia Zhao‐Lin Sun Zhi‐Xiong Li Cheng‐Gang Huang 《Biomedical chromatography : BMC》2010,24(11):1147-1151
To profile the anti‐Coxsackie virus B3 constituents of Radix Astragali, an HPLC‐DAD‐MSn analytical method, combined with an in vivo test, has been developed to identify the constituents of the active part, which has been demonstrated to have potency to inhibit the proliferation of virus in cardiac muscle, alleviate infraction in heart and elevate the survival rate of the animal. By comparing their retention time and MS data with those obtained from the authentic compounds and the published data, a total of 19 compounds, including 11 isoflavonoids and eight saponins, were identified, among which one pterocarpane glucoside was reported for the first time. The present study provides an approach to rapidly screening bioactive constituents in traditional Chinese medicines. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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An efficient and convenient three‐component A3 coupling reaction of aldehyde, amine and alkyne via C? H activation with CuI alone as the catalyst in PEG is developed, providing a wide range of propargylamines with yields ranging from moderate to excellent. Additionally, the catalyst system was recovered and reused several times without evident loss in activity. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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In this work, we introduce a new concept which is obtained by defining a new compatibility condition between Lie algebras
and Lie coalgebras. With this terminology, we describe the interrelation between the Killing form and the adjoint representation
in a new perspective. 相似文献
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