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采用一种高效的pH区带逆流色谱方法分离制备金果榄中的巴马汀和药根碱,以氯仿-甲醇-水(4∶3∶2)为溶剂系统,在上相中加入20 mmol/L的HCl作为固定相,在下相中加入10 mmol/L三乙胺作为流动相,流速为2.0 mL/min,仪器转速为850 r/min。经一次pH区带逆流色谱分离,从2 g粗提物中得到512 mg巴马汀和421 mg药根碱。经高效液相色谱(HPLC)分析,其纯度均大于95%,采用MS,~1H NMR和~(13)C NMR对其化学结构进行确定。该方法具有简便、快捷、重现性好、上样量大等特点,可快速高效地分离制备金果榄中的巴马汀和药根碱。  相似文献   
2.
The in vivo and in vitro metabolism of jatrorrhizine has been investigated using a specific and sensitive LC/MS/MS method. In vivo samples including rat feces, urine and plasma collected separately after dosing healthy rats with jatrorrhizine (34 mg/kg) orally, along with in vitro samples prepared by incubating jatrorrhizine with rat intestinal flora and liver microsome, respectively, were purified using a C(18) solid-phase extraction cartridge. The purified samples were then separated with a reversed-phase C(18) column with methanol-formic acid aqueous solution (70:30, v/v, pH3.5) as mobile phase and detected by on-line MS/MS. The structural elucidation of the metabolites was performed by comparing their molecular weights and product ions with those of the parent drug. As a result, seven new metabolites were found in rat urine, 13 metabolites were detected in rat feces, 11 metabolites were detected in rat plasma, 17 metabolites were identified in intestinal flora incubation solution and nine metabolites were detected in liver microsome incubation solution. The main biotransformation reactions of jatrorrhizine were the hydroxylation reaction, the methylation reaction, the demethylation reaction and the dehydrogenation reaction of parent drug and its relative metabolites. All the results were reported for the first time, except for some of the metabolites in rat urine.  相似文献   
3.
采用亲和色谱法研究了β2-肾上腺素受体(β2-AR)与中药活性小分子盐酸巴马汀(Pa)和盐酸药根碱(Ja)的相互作用.前沿色谱法说明Pa与β2-AR之间存在一类结合位点,Ja与β2-AR之间存在两类结合位点.在pH 7.4,25℃时,用竞争洗脱法测得了Pa与β2-AR的结合常数为2.93×104 L?mol-1,结合位点浓度为1.13×10-4 mol?L-1,Ja在β2-AR低、高亲和力位点上的结合常数分别为1.93×104和1.56×105 L?mol-1,对应的结合位点浓度分别为1.25×10-4 mol?L-1和1.00×10-5 mol?L-1,两类结合位点数的比值为93∶7,且Pa和Ja在低亲和力位点上存在竞争作用.热力学研究表明,静电力是这两种药物与β2-AR之间作用的主要驱动力.  相似文献   
4.
基于共价固定化苯嵌蒽酮荧光猝灭的药根碱光化学传感器   总被引:1,自引:0,他引:1  
将3-烯丙氧基苯嵌蒽酮与丙烯酸胺和N,N’-亚甲基双丙烯酰胺一起共聚在硅烷化含乙烯基团的石英玻片上,制成了可传感药根碱的光极膜。药根碱能快速可逆挥灭光极膜的荧光。在1.00×10-5~4.00×10~(-4)mol/L范围内,膜对药根碱响应呈线性关系。由于共价固定化作用阻止了敏感试剂的流失,传感器显示出好的稳定性。常见无机阴、阳离子及一些常见药物对测定无显著干扰。传感器用于尿样中药根碱测定的回收率在102%~105%之间。  相似文献   
5.
高效毛细管电泳测定黄连及成药中小檗碱型生物碱的含量   总被引:25,自引:0,他引:25  
张国华  王延琮  张永友  王磊  张玉奎 《色谱》1995,13(4):247-249
报道了黄连及成药中七种小檗碱型生物碱的高效毛细管电泳分离测定方法。缓冲液由65%磷酸氢二钠(用磷酸调pH7.0)和15%甲醇组成。方法具有良好的精密度、回收率及线性关系。并用此法定量测定了黄连及六种成药中三种生物碱(小檗碱、巴马汀、药根碱)的含量。  相似文献   
6.
A simple, sensitive and continuous on-line stacking technique using head-column (HC)-field amplified sample injection (FASI) and sweeping was developed by combination of flow injection with micellar electrokinetic chromatography. Berberine, palmatine and jatrorrhizine were selected as model mixture to demonstrate this stacking method. Based on the characteristic of a 16-way injection valve (16-V), a sample was injected electrokinetically into a capillary after the introduction of a plug of water. Under optimum conditions, 64–86-fold improvement in the detection sensitivity was obtained for the analytes and the sample throughput can reach up to 24 h−1 using the background electrolyte containing 240 mM ammonium acetate (pH 4.7), 30% (v/v) ethanol, and 2% (v/v) polyoxyethylene sorbitan monolaurate (Tween 20). The repeatabilities (n = 4) reached relative standard deviation values of 1.2, 2.7 and 3.1% for the peak areas and 1.6, 3.3 and 3.8% for peak heights of berberine, palmatine and jatrorrhizine, respectively. The limit of detection for the berberine, palmatine and jatrorrhizine was found to be 27, 26, 22 ng mL−1 (S/N = 3).  相似文献   
7.
Quaternary protoberberine alkaloids are a class of natural dyes characterized by bright colors ranging from yellow to orange. As they present a strong fluorescence emission, their analysis by Raman spectroscopy is limited to specific techniques such as Fourier transform (FT)‐Raman and spectral shift Raman techniques such as shifted subtracted Raman difference spectroscopy (SSRDS) and shifted excitation Raman difference spectroscopy (SERDS). In a previous article, we successfully used surface‐enhanced Raman scattering (SERS) in the analysis of the alkaloid dye berberine in an ancient textile. The examination of the Raman and SERS spectra of berberine in combination with density functional theory (DFT) calculations indicated a flat adsorption geometry of the molecule on the Ag surface. In this article we extend that work to the study of related protoberberine alkaloids, palmatine, jatrorrhizine, and coptisine. The same adsorption geometry as in berberine was deduced. We found that the four alkaloids, although minimally different in their chemical structures, could be differentiated by the position of marker bands. Those bands are the most enhanced ones in the SERS spectra, which appear in the 700–800 cm−1 region. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
8.
非水毛细管电泳测定黄连饮片中5种生物碱   总被引:1,自引:0,他引:1  
建立了一种非水毛细管电泳(NACE)同时测定黄连饮片生品与炮制品中小檗碱、巴马汀、药根碱、木兰碱和黄连碱含量的方法。分别考察了非水溶剂、缓冲液体系及其浓度和pH、运行电压、运行温度和检测波长等条件对实验结果的影响。在优化的实验条件下,选择非水毛细管电泳分离模式,以40 mmol/L乙酸钠-40 mmol/L乙酸铵的无水甲醇缓冲溶液(pH 5.8)为电泳介质,未涂渍标准熔融石英毛细管(64.5 cm×75 μm,有效长度56 cm)为分离通道,检测波长为254 nm,分离电压为25 kV,压力进样(5 kPa×6 s),柱温为20 ℃。结果显示,5种生物碱在20 min内可实现基线分离,加标回收率为98.37%~101.03%。该方法简单、准确,重现性较好,可用于黄连饮片内在质量的评价和控制。  相似文献   
9.
戈早川  周建明 《分析化学》2004,32(1):99-101
以2%CPC-醋酸乙酯(9:1)胶束溶液为展开剂,在聚酰胺薄膜上成功地分离了小檗碱、巴马汀和药根碱。以345nm为测定波长,550nm为参比波长进行扫描测定,建立了一种新的同时测定黄连及其制剂中小檗碱、巴马汀和药根碱的胶束薄层扫描法。小檗碱、巴马汀和药根碱的线性范围分别为0.2—2.4、0.1—1.0和0.1—1.0μg;回收率分别为97.7%-99.4%、101.7%~102.6%和96.7%-97.8%;相对标准偏差分别为1.4%-1.7%、1.9%-2.7%和1.8%-2.2%。  相似文献   
10.
Summary A simple, rapid and effective capillary electrophoresis method was developed for the characterization of 10 different species ofMahonia. A fingerprint of the extract of each species was constructed using a mixed buffer of borate and phosphate, containing methanol, pH 8.0. The effective electrophoretic mobility and % normalized area of each peak in electrophoregrams were evaluated to characterize various species. Three alkaloids: berberine, palmatine and jatrorrhizine were found in all 10 species. The CE technique appears to provide a powerful tool for the identification and quality control of plant drugs.  相似文献   
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