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101.
Qiaoxia Liu Binbin Zhou Xinliang Wang Yanxiong Ke Yu Jin Lihui Yin Xinmiao Liang 《Journal of separation science》2012,35(23):3317-3325
A search library about benzylisoquinoline alkaloids was established based on preparation of alkaloid fractions from Rhizoma coptidis, Cortex phellodendri, and Rhizoma corydalis. In this work, two alkaloid fractions from each herbal medicine were first prepared based on selective separation on the “click” binaphthyl column. And then these alkaloid fractions were analyzed on C18 column by liquid chromatography coupled with tandem mass spectrometry. Many structure‐related compounds were included in these alkaloids fractions, which led to easy separation and good MS response in further work. Therefore, a search library of 52 benzylisoquinoline alkaloids was established, which included eight aporphine, 19 tetrahydroprotoberberine, two protopine, two benzyltetrahydroisoquinoline, and 21 protoberberine alkaloids. The information of the search library contained compound names, structures, retention times, accurate masses, fragmentation pathways of benzylisoquionline alkaloids, and their sources from three herbal medicines. Using such a library, the alkaloids, especially those trace and unknown components in some herbal medicine could be accurately and quickly identified. In addition, the distribution of benzylisoquinoline alkaloids in the herbal medicines could be also summarized by searching the source samples in the library. 相似文献
102.
用动态涂敷法制备了对甲苯磺酸正丁铵玻璃毛细管柱柱1(固定液浓度为7.5%,柱尺寸为35m×0.35mmi.d.)和柱2(固定液浓度为9.2%,柱尺寸为35m×0.30mmi.d.),所用溶剂是丙酮和甲醇(2:1V/V)的混合溶剂,并对柱性能进行了考察。结果表明,这种色谱固定相具有较强的极性并对饱和烃、芳香烃、饱和酸、芳香酸、极性异构体等具有良好的分离效果。 相似文献
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Wei Min WANG Xin Miao LIANG* Qing ZHANG Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 《中国化学快报》2001,(3)
Recent legislation in many countries requires extensive testing of all manufactured chemicals for environmental evaluation and registration. Among the requirements are water solubility, solvent (usually octanol) - water partition coefficient, soil adsorption and bioconcentration factors in aquatic organisms. Soil adsorption influences the extent of vaporization of a compound from the soil surface and its lateral (run-off) or vertical transport including groundwater contamination. Additionally,… 相似文献
106.
根据 30万t乙烯工程“橡胶”装置中生产工艺控制的实际需要 ,研究了在线分析己烷中痕量四氢呋喃的气相色谱柱系统。使用自制的 7μm特厚膜甲基硅氧烷大孔径弹性石英毛细管柱 ,通过试验不同条件下色谱柱的分离特性及研究组分在柱内的运动轨迹 ,给出了总的柱切换时间程序。在上述基础上 ,完成了正己烷、环己烷中 10 -6(体积分数 )级的四氢呋喃分析。现场应用一年多的实践表明 ,所研制的柱系统从分析时间、运行稳定性、定量准确性 (相对标准偏差小于 5 % )等方面均满足工艺控制的要求。 相似文献
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The pentafluorophenyl (PFP) column is emerging as a new advancement in separation science to analyze a wide range of analytes and, thus, its separation mechanism at supramolecular level is significant. We developed a mechanism for the separation of ibuprofen and omeprazole using different combinations (ranging from 50:50 to 60:40) of water–acetonitrile containing 0.1% formic acid as the mobile phase. The column used was Waters Acquity UPLC HSS PFP (75 × 2.1 mm, 1.8 μm). The reverse order of elution was observed in different combinations of the mobile phases. The docking study indicated hydrogen bonding between ibuprofen and PFP stationary phase (binding energy was −11.30 kJ/mol). Separation at PFP stationary phase is controlled by hydrogen bonding along with π–π interactions. This stationary phase may be used to analyze both aromatic and aliphatic analytes. The developed mechanism will be useful to separate various analytes by considering the possible interactions, leading to saving of energy, time and money. In addition, this work will be highly useful in preparative chromatography where separation is the major problem at a large scale. Moreover, the developed LC‐MS‐QTOF method may be used to analyze ibuprofen and omeprazole in an unknown sample owing to the low value of detection limits. 相似文献
110.
《Biomedical chromatography : BMC》2018,32(10)
Shenkang injection is a traditional Chinese formula with good curative effect on chronic renal failure. In this paper, a novel, rapid and sensitive ultra‐high‐performance liquid chromatography coupled with Q Exactive hybrid quadrupole Orbitrap high‐resolution accurate mass spectrometry was developed and validated for simultaneous determination of seven bioactive constituents of Shenkang injection in rat plasma and tissues after intravenous administration. Acetonitrile was used as a protein precipitation agent in biological samples disposal with carbamazepine as internal standard. The chromatographic separation was carried out on a C18 column with a gradient mobile phase consisting of acetonitrile and water (containing 0.1% formic acid). The MS analysis was performed in the full‐scan positive and negative ion mode. The lower limits of quantification for the seven analytes in rat plasma and tissues were 0.1–10 ng/mL. The validated method was successfully applied to tissue distribution and pharmacokinetic studies of Shenkang injection after intravenous administration. The results of the tissue distribution study showed that the high concentrations of seven constituents were primarily in the kidney tract. This is the first report of the application of Q‐Orbitrap with full‐scan mass spectrometry in tissue distribution and pharmacokinetic studies of Shenkang injection. 相似文献