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A tandem high-performance liquid chromatography and time-of-flight mass spectrometry method has been developed for rapid separation and identification of alkaloids in rat plasma after oral administration of rhizoma Corydalis extracts. Compounds were separated on a Zorbax XDB-C(18) column and the linear gradient elution was used with the mobile phase consisting of ammonium acetate-0.01% acetic acid and acetonitrile. Mass spectra were acquired by electrospray ionization in the positive ion mode. Fifteen components were detected in vitro, among which 12 components were rapidly identified based on the accurate-mass capability of time-of-flight analyzer. Eleven prototype components were detected in dosed rat plasma (in vivo). Three isomers, which had the same [M+H](+) ion at m/z 356.1856, were distinguished as glaucine, tetrahydropalmatine, and corybulbine by dynamic adjustment of fragmentor voltages. This study developed a rapid and sensitive method that was successfully utilized for screening the active ingredients of rhizoma Corydalis in rat plasma, which provided helpful information for further pharmacokinetic research of active components in this medicine. 相似文献
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溶剂浮选法分离富集大黄中的有效成分 总被引:1,自引:0,他引:1
采用溶剂浮选法对大黄提取液中的芦荟大黄素、大黄素、大黄酚以及大黄素甲醚进行了分离富集,并用高效液相色谱法分别测定了其含量。考察了料液浓度、浮选溶剂、浮选时间、浮选液pH值、氮气流速和电解质NaCl浓度对浮选效率的影响,并与泡沫浮选法和溶剂萃取法进行了比较。结果表明:溶剂萃取效果最差,泡沫浮选次之,溶剂浮选法分离富集效果最好。当料液浓度为6.4mg/mL,浮选时间为30min,浮选液pH一1~2,氮气流速为20mL/min,电解质NaCl浓度为0.4mol/L时,溶剂浮选效率最佳。 相似文献
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In vitro and in vivo identification of metabolites of magnoflorine by LC LTQ‐Orbitrap MS and its potential pharmacokinetic interaction in Coptidis Rhizoma decoction in rat
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Baojuan Xue Yuanyuan Zhao Qing Miao Peipei Miao Xiaoyan Yang Guixia Sun Jin Su Jing Ye Baohong Wei Yuanyuan Zhang Yujie Zhang 《Biomedical chromatography : BMC》2015,29(8):1235-1248
Magnoflorine, an important aporphine alkaloid in Coptidis Rhizoma, is increasingly attracting research attention because of its pharmacological activities. The in vivo and in vitro metabolism of magnoflorine was investigated by LC LTQ‐Orbitrap MS. In vivo samples including rat urine, feces, plasma and bile were collected separately after both oral (50 mg kg?1) and intravenous administration (10 mg kg?1) of magnoflorine, along with in vitro samples prepared by incubating magnoflorine with rat intestinal flora and liver microsome. As a result, 12 metabolites were found in biological samples. Phase I metabolites were identified in all biological samples, while phase II metabolites were mainly detected in urine, plasma and bile. In a pharmacokinetic study, rats were not only dosed with magnoflorine via oral (15, 30 and 60 mg kg?1) and intravenous administration (10 mg kg?1) but also dosed with Coptidis Rhizoma decoction (equivalent to 30 mg kg?1 of magnoflorine) by intragastric administration to investigate the interaction of magnoflorine with the rest of compounds in Coptidis Rhizoma. Studies showed that magnoflorine possessed lower bioavailability and faster absorption and elimination. However, pharmacokinetic parameters altered significantly (p < 0.05) when magnoflorine was administered in Coptidis Rhizoma decoction. Oral gavage of Coptidis Rhizoma decoction decreased the absorption and elimination rates of magnoflorine, which revealed that there existed pharmacokinetic interactions between magnoflorine and the rest of ingredients in Coptidis Rhizoma. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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苦黄注射液中大黄蒽醌含量测定方法改进 总被引:2,自引:0,他引:2
按苦黄注射液原质量标准(草案)中测定方法,大黄蒽醌用氯仿提取,阴性试验结果为苦黄注射液大黄蒽酯标示量的16.50%(n=5),结果偏高;改用石油醚提取,降为6.15%,重复性试验的RSD为1.44%(n=5),加标回收率为101.8%(n=5),显色在1-4h内稳定,表明该法是可行的。 相似文献
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Structural elucidation and identification of alkaloids in Rhizoma Coptidis by electrospray ionization tandem mass spectrometry 总被引:2,自引:0,他引:2
Simple, convenient, sensitive and accurate analytical methods are needed for the structural characterization and identification of alkaloid components in Rhizoma Coptidis in traditional Chinese herbal medicine, which has important bioactivity. In this work, the identification of alkaloid compounds in Rhizoma Coptidis was investigated by obtaining molecular mass information using electrospray ionization mass spectrometry (ESI-MS). Multi-stage tandem mass spectrometric (ESI-MS(n)) data for the alkaloid compounds were used for detailed structural characterization, then structure information was obtained by comparison of the fragmentation mechanisms of both alkaloids in Rhizoma Coptidis and standard samples of berberine, palmatine, coptisine and jatrorrhizine by MS. Based on the results obtained, the structure of a novel compound was elucidated. The results of the experiments demonstrate that ESI-MS(n) is a sensitive, selective and effective tool for the rapid determination of alkaloids in Rhizoma Coptidis. 相似文献
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