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目的:建立测定胆仙胶囊中绿原酸含量的方法。方法采用高效液相色谱法。色谱柱为依利特C18(4.6mm ×250mm,5μm),流动相为乙腈-0.1%磷酸水溶液(20∶80,V/V),流速为1.0mL? min -1,检测波长为327nm,进样量为10μL。结果绿原酸的质量浓度线性范围为14.0~140μg? mL-1(r=0.9992,n=6);平均加样回收率为99.52%,RSD为0.73%(n=9)。结论本方法快速、简便、准确、重现性良好,可用于该制剂的质量控制。 相似文献
104.
Lakkireddy Prakash Malipeddi Himaja Belly Ramakrishna Yadav Arumalla Maheshwara Reddy 《Scientia pharmaceutica》2015,83(3):453-463
Cost-effective isolation methods were developed on preparative HPLC, flash LC, and simulated moving bed (SMB) to prepare the process impurity, 3-(aminomethyl)-5-methylhex-4-enoic acid (4-ene impurity), of pregabalin. By a thorough experimental study on the different isolation techniques available, it was concluded that SMB was the most cost-effective. Hence, it was a continuous chromatography that utilized the advantage of SMB so that a high quantity of the impurity was generated in a short period of time. SMB was equipped with eight reversed-phased columns and was used to separate the process impurity of pregabalin. The effects of flow rate in zone 2 (Q2) and 3 (Q3), as well as switching time, on the operating performance parameters like purity, productivity, and desorbent consumption were studied. Operating conditions leading to more than 90% purity in the raffinate outlet stream were identified, together with those achieving optimal performance. All of these developed methods are novel, cost-effective, and can be applied to the isolation of other process- and stability-related impurities of pregabalin. 相似文献
105.
Quantitative toxicoproteomic analysis of zebrafish embryos exposed to a retinoid X receptor antagonist UVI3003 下载免费PDF全文
Liang Zheng Jianlan Yu Huahong Shi Liang Xia Qi Xin Qiang Zhang Heng Zhao Ji Luo Wenhai Jin Daoji Li Junliang Zhou 《Journal of applied toxicology : JAT》2015,35(9):1049-1057
Retinoid X receptor (RXR) antagonists, including some environmental endocrine disruptors, have a teratogenic effect on vertebrate embryos. To investigate the toxicological mechanism on the protein expression level, a quantitative proteomic study was conducted to analyze the proteome alterations of zebrafish (Danio rerio) embryos exposed to gradient concentrations of a representative RXR antagonist UVI3003. Using isobaric Tags for Relative and Absolute Quantitation (iTRAQ) labeling coupled nano high‐performance liquid chromatography‐tandem mass spectrometry (nano HPLC‐MS/MS), in total 6592 proteins were identified, among which 195 proteins were found to be differentially expressed by more than a two‐fold change in exposed groups compared with the control. Gene ontology analysis showed that these differential proteins were mostly involved in anatomical structure development, biosynthetic process, ion binding and oxidoreductase activity. Moreover, the biological pathways of translation, lipoprotein metabolism, cell survival and gluconeogenesis were intensively inhibited after exposure. Some significantly downregulated proteins such as apolipoprotein A‐I and vitellogenin and upregulated proteins such as calcium activated nucleotidase 1b, glutathione S‐transferase and glucose 6‐dehydrogenases showed a strong dose‐dependent response. The results provided new insight into the molecular details of RXR antagonist‐induced teratogenicity and added novel information of pathways and potential biomarkers for evaluation of RXR interfering activity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
106.
On the Homogeneity of Metallocene Ethylene–Propylene Copolymers as Investigated by Multiple Fractionation Techniques 下载免费PDF全文
Mohau Justice Phiri Anita Dimeska Harald Pasch 《Macromolecular chemistry and physics.》2015,216(15):1619-1628
The chemical heterogeneity of ethylene–propylene copolymers by multiple fractionation techniques is addressed. Three metallocene copolymer samples with different ethylene contents, ranging from 30 to 50 mol% are analyzed using bulk methods to confirm their molecular heterogeneity. In a second step, the samples are fractionated by temperature rising elution fractionation (TREF) to obtain fractions at 30, 60, 90, and 130 °C. These fractions are subsequently analyzed regarding their thermal and molecular properties. Differential scanning calorimetry, crystallization analysis fractionation, and high‐temperature high performance liquid chromatography (HT‐HPLC) results reveal that the TREF fractions collected at 130 °C are mainly due to polypropylene homopolymer, which is rather unexpected considering the high ethylene contents of the bulk samples. Most importantly, HT‐HPLC reveals a remarkably high chemical heterogeneity of the fractions and thus the bulk samples. Solution 13C NMR provides the comonomer contents and sequence distributions of the fractions. These indicate that the same TREF fractions from different samples have distinctively different chemical compositions.
107.
目的:建立一个采用高效液相色谱法测定养阴退热颗粒提取物中芍药苷含量的方法。方法:Odshypersil色谱柱(4.6 mm×250 mm,5μm),乙腈-0.1%磷酸溶液洗脱,柱温度32℃,流量0.8 m L/min,检测波长230 nm。结果:芍药苷在在5~200μg/m L范围内线性关系良好,平均回收率为99.83%,RSD为0.76%,A类不确定度Ua=0.003417.结论:3批样品的抽检结果显示,该方法准确、方便、重复性好,可用于测定芍药苷在养阴退热颗粒提取物中的含量。 相似文献
108.
目的::建立高效液相色谱法同时测定承德产山楂叶中牡荆素葡萄糖苷、牡荆素鼠李糖苷、金丝桃苷和槲皮素含量的方法。方法:色谱柱为Agilent ZORBAX SB-C18(4.6mm×250mm,5μm);流动相为0.5%甲酸水-乙腈-甲醇-四氢呋喃溶液,梯度洗脱;流速1.0ml/min;检测波长370nm;柱温30℃。结果:牡荆素葡萄糖苷、牡荆素鼠李糖苷、金丝桃苷和槲皮素的线性范围分别为9.38-300μg/ml、15.9-510μg/ml、4.51-144μg/ml、0.28-9.0μg/ml;平均加样回收率分别为100.2%(RSD=1.8%)、99.6%(RSD=1.5%)、99.4%(RSD=2.0%)、100.8%(RSD=1.5%)。结论:含量测定结果显示不同产地山楂叶中四种黄酮类成分含量的差异较大(RSD为9.98-31.39%)。 相似文献
109.
目的:建立组织中百草枯质量分数高效液相色谱检测方法,观察百草枯染毒大鼠模型肺组织中百草枯含量的动态变化趋势。方法样品处理采用35%高氯酸处理。流动相为0.1 mol/L磷酸缓冲液-乙腈;流速1.0 ml/min ;柱温28℃;检测波长258 nm。结果所采用方法在2~200μg/ml范围内线性关系良好。平均绝对回收率为91.4%,RSD均小于3%;平均相对回收率为100.67%,RSD均<6%。日内和日间RSD均<6%,冻融及冻存后百草枯样品质量分数测定结果无显著性差异。结论高效液相色谱法快速、准确,无组织中杂质干扰,适用于百草枯染毒大鼠模型肺组织中百草枯质量浓度的分析测定。 相似文献
110.
目的 比较中国卫生部及美国药典(USP35)颁布的氨磷汀及其相关物质的高效液相(HPLC)测定方法.方法 美国药典USP35测定方法采用C8色谱柱,流动相采用7∶18(甲醇∶0.94g/L己烷磺酸)溶液,检测波长为220nm,流速1.0mL/min;中国卫生部的标准采用C18色谱柱,流动相采用1∶1(甲醇∶3.5mmol/L辛烷磺酸钠)溶液,检测波长均为220nm,流速0.7 mL/min.结果 两种方法检测氨磷汀及相关物质都符合对杂质的要求.结论 美国药典USP35的检测方法对氨磷汀及相关物质检测的质量控制更好. 相似文献