柱层析-HPLC法测定阳强保肾丸中淫羊藿苷的含量

目的:建立以柱层析-高效液相色谱法测定阳强保肾丸中淫羊藿苷含量的方法。方法:色谱柱为十八烷基硅烷键合硅胶(200mm×4·6mm,10μm),流动相为0·075mol·L-1磷酸溶液-乙氰(73∶27),检测波长为270nm。结果:淫羊藿苷检测浓度在10~18μg·mL-1范围内与峰面积积分值呈良好线性关系(r=0·9995);平均加样回收率为94·35%,RSD=1·12%(n=6)。结论:本法简便、准确、重现性好,可用于阳强保肾丸的质量控制。     

毛苞瓜叶乌头生物碱成分的研究

目的 研究毛苞瓜叶乌头根中的生物碱化学成分.方法 酸提碱沉提取总碱,硅胶层析法分离,波谱法鉴定结构.结果 分离到6个已知的去用二萜生物碱,分别为滇乌碱(yunaconitine)、塔拉萨敏(talasamine)、瓜乌定(hemsleyadine)、拳乌宁乙(circinanine B)、黄草乌碱丁(schaconitine)和senbusine A.结论 应用光谱法和与已知物TLC对照的方法鉴定了所有化合物的结构.     

柱色谱-分光光度法测定菝葜中总黄酮的含量

目的 建立测定菝葜中总黄酮含量的方法.方法 测定波长500 nm,以芦丁为对照品,采用柱色谱-分光光度法测定不同产地菝葜中总黄酮的含量.结果 芦丁在8.02～48.12 μg·ml-1范围内线性关系良好(r=0.9996),平均回收率为96.70%,RSD=1.24%.结论 所建方法操作简便、结果准确、重复性好,可用于药材的质量控制.     

柱层析——分光光度法测定益母草中总黄酮含量

目的建立益母草药材总黄酮含量测定方法,并对药材资源进行初步考察。方法以芦丁为对照品,样品经聚酰胺柱分离纯化,三氯化铝试剂显色后,采用紫外分光光度法在412 nm波长处测定总黄酮含量。结果芦丁在4.8~29.0μg/m l范围内与吸光度有良好线性关系,r=0.9996,平均回收率为102%,RSD=3%。结论该方法操作简单、准确,可作为益母草药材的质量分析方法。     

Fast liquid chromatographic-tandem mass spectrometric (LC-MS-MS) determination of metformin in plasma samples

Liquid chromatographic–tandem mass spectrometric (LC–MS–MS) methods for the determination of metformin in plasma from different species are presented. The first method employed a YMC cyano 2 mm×50 mm, 3 μm analytical column. For minimum sample preparation direct injection of samples after protein precipitation was performed. The polar column used with highly organic mobile phases provided a normal phase retention mechanism. The elution conditions were optimized to obtain reproducible peak areas and good peak shape. A step gradient from 100% acetonitrile to acetonitrile–water 80:20 (v/v) containing 10 mM ammonium acetate and 1% acetic acid was applied, leading to a sample-to-sample cycle time of 2 min. In a second method, a column-switching LC–MS–MS assay for on-line trapping was developed. The analyte and internal standard were trapped on a YMC cyano 2 mm×10 mm, 5 μm column using acetonitrile–methanol 95:5 (v/v). Elution was performed isocratically in back-flush mode on to the analytical column (YMC cyano 2 mm×50 mm, 3 μm) using 10 mM ammonium acetate in acetonitrile–water 80:20 (v/v) with 1% formic acid. With this approach, the signal-to-noise ratio was improved and the run time could be shortened to 1 min. Calibration samples were prepared in the matrix to be assayed in the range of 10–10,000 ng/ml. Quality control (QC) samples were prepared at 40, 400 and 4000 ng/ml and interspersed with the unknown study samples in the assays. Deviations for precision and accuracy were less than 20% for the lower limit of quantification (LLOQ) and low QC sample and less than 15% for other calibrators and QCs.     

Intrinsic connections in cat visual cortex: a combined anterograde and retrograde tracing study

Area 18 of cat visual cortex was examined for intrinsic axons following small, columnar injections of an anterograde tracer,Phaseolus vulgaris leucoagglutinin (PHA-L). Locally projecting axons radiated from the injection site and branched to form 10–15 discrete, approximately circular patches 500–750 μm in diameter consisting of many bouton-studded terminal arborizations. Labeled fibers and boutons ramified densely in layers I, II/II, V, and VI, and were noticeably less dense in layer IV. Afferent and efferent pathways originating from the same cortical columns were studied by injecting a mixture of PHA-L and wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). Between 10 and 15 patches of cells retrogradely labeled by WGA-HRP surrounded each injection site. Within a patch, labeled cells were found in all layers and included both pyramidal and non-pyramidal cells. The distribution of PHA-L labeling was similar to that obtained when PHA-L was injected alone. Most often, the labeled patches resulting from injections of such mixtures contained both anterograde and retrograde labeling. However, patches consisting of retrograde labeling alone and of anterograde labeling alone were also observed, indicating that the local connections linking neighboring cortical columns were not always reciprocal.     

决明子中大黄素的提取、分离和纯化方法的研究

目的寻求获得高纯度大黄素的可行性。方法先用稀硫酸溶液将蒽醌苷水解成苷元，再用热氯仿将苷元提取出来，然后用PH8．0缓冲液将大黄酸从氯仿液中除去，再用0．2％NaOH反复萃取将大黄素从氯仿液中提取出来，用层析柱法将大黄素分离纯化，经用丙酮反复多次重结晶可得纯度较高的大黄素。结果本方法提纯得到的大黄素的纯度达到98．1％以上。结论该方法操作简单、实用性强、成本低、可以推广应用。     

六应丸中丁香酚的气相色谱测定法

中成药六应丸是由蟾酥、牛黄、冰片、丁香等药物组成,具有解毒、消炎、退肿、止痛等功效。本文探索了生药公丁香及成药六应丸中的丁香酚的气相色谱测定法,并比较了不同的提取过程对含量测定的影响。方法简便,准确。     

柱层析法纯化灯盏乙素的研究

目的优选灯盏乙素的柱层析纯化条件。方法采用高效液相色谱法检测纯度,考察了不同固定相和流动相对灯盏乙素分离效果的影响。结果灯盏乙素的最佳纯化工艺条件为:固定相200-300目的硅胶柱,流动相V(CH2Cl2)∶V(CH3OH)=5∶1,常压洗脱。结论该方法操作简单,分离效果好,使用成本低。