Rapid analysis of components in Rhizoma Anemarrhenae by HPLC-DAD-MS and HPLC-DAD-TOFMS

A global quality control method based on high performance liquid chromatography (HPLC) coupled with diode array detection (DAD), single quadrupole mass spectrometry (MS) and time-of-flight mass spectrometry (TOFMS) was developed for simultaneous determination of seven major components (mangiferin, neomangiferin, timosaponin E1, timosaponin E, timosaponin BⅡ, timosaponin BⅢ, and timosaponin AⅢ) and identification of most components in extracts of Rhizoma Anemarrhenae (RA). HPLC analysis was performed on an Agilent SB-C18 column (4.6 mm×150 mm, 5 μm) by gradient elution using acetonitrile and water-acetic acid(100∶0.05, v/v) as the mobile phase. Seven major components in RA were successfully separated. This quantitative method was fully validated in respect of the following performance criteria: linearity, precision, repeatability, stability, accuracy, limits of detection (LOD) and quantification (LOQ). A formula database of known compounds in RA was established, against which, most of the reported components in this herbal extract were identified effectively based on the extract masses acquired by TOFMS. This qualitative and quantitative method was successfully used to analyze the components in 10 batches of RA samples collected from different regions in China. This global quality control method, which consisted of HPLC-DAD-MS assay of seven major components and unambiguous identification of nineteen components, is suitable for routine quantification and comprehensive quality control of RA.     

RP-HPLC method for the simultaneous determination of daidzein,genistein and formonetin in Solanum Lyratum Thunb

A rapid method for the simultaneous determination of daidzein, genistein and formonetin in solanum Lyratum Thunb by high performance liquid chromatography (HPLC) was developed. Separation was achieved on a Diamonsil C18 column (250 mm×4.6 mm, 5 μm) with isocratic elution, using a mobile phase of methanol-tetrahydrofuran-water (44∶3∶53, v/v). The wavelength was set at 260 nm and column was maintained at 35 ℃. The linear ranges of daidzein, genistein and formonetin were 1.0-40.0, 0.1-4.0 and 0.1-4.0 μg/mL, respectively. The average recoveries were between 98.4% and 101.3%. This method could be used for the quality control of Solanum lyratum Thunb due to its simplification, reliability, rapidity and excellent precision.     

Determination of enantiomeric impurity of etomidate by high performance liquid chromatography

Objective To determine enantiomeric impurity of etomidate using high performance liquid chromatography. Methods (R)-etomidate and (S)-etomidate were isopropanol-n-hexane. The flow rate of the mobile phase was 0.5mL/min. The detected wavelength was 242nm. Results (R)-etomidate and (S)-etomidate could be separated completely under these conditions. The precision of (R)-etomidate was 1.57% (n=3). The limit of detection of (R)-etomidate was 4.25ng/mL. The average percentage content of (S)-etomidate was 0.09% in the samples. Conclusion The method was repeatable and sufficiently sensitive to determine the enantiomeric impurity of etomidate. It allows the quantitation of the impurities at the 0.085% (w/w) level relative to etomidate at a concentration of the test solution of 5mg/mL.     

HPLC-MS法测定人血浆中羧甲司坦浓度

目的 建立一种灵敏、高效、快速的高效液相色谱-质谱分析方法,测定人血浆中羧甲司坦的血药浓度.方法 100mL/L高氯酸沉淀血浆蛋白,上清液反相高效液相色谱分离,电喷雾离子阱质谱法检测血浆样品中的羧甲司坦,多级反应模式选择离子法定量.结果 方法检测限为0.01μg/mL,线性范围为0.2～200.0μg/mL,回收率为89.2%～105.6%.结论 该方法精密、灵敏、准确,可用于生物样品中羧甲司坦的测定.     

崛起中的汽配产业新城——走进江苏省泰兴经济开发区城东工业园

2006年8月,适逢沿江开发大潮,为抢抓机遇快速发展,合理配置生产要素,高效利用各类资源,鼓励全市工业项目向重点园区聚焦,泰兴市委决定在原姚王工业集聚区成立江苏省泰兴经济开发区城东工业园。至此,日新月异,三年巨变,一座夺目的新兴工业城在泰兴市东郊崛起。     

低成本构建高效铁路内部企业财务管理信息系统

从实际工作业务需求出发,设计以低成本构建高效的铁路内部公司的财务管理信息系统.     

运营隧道无损检测管理办法

运营隧道检测工作难度大，作业安全要求高，编写本文是为了细化运营隧道无损检测的方法和要求，确保检测工作安全、准确、高效进行。     

大气环境中微量甲醛的色谱测定法

叙述了用色谱法测定大气环境中微量甲醛的各种方法，其中包括气相色谱法，液相色谱法和高效液相色谱法，离子色谱法，薄层色谱法和气相色谱法－质谱法，就有关的内容做了介绍。     

钙拮抗剂尼群地平的反相高效液相色谱分析及其在家兔体内的分布

对兔血浆及组织器官中钙拮抗剂尼群地平的分析方法进行了研究，建立了反相高效液相色谱（RP-HPLC）的内标测定法。样品在弱碱性条件下经环已烷-异丙醇（96．5：3．5）提取，用YWGC18反相柱，以地尔硫作内标，甲醇：50mmol／L磷酸盐缓冲液（70：30）pH6．8为流动相，UV236nm检测。方法最低检测限约为10ng，血药浓度在21．6～216μg／L之间，尼群地平的量与其峰面积比值之间，线性关系良好，回归方程为Y＝0．00672X－0．013，r＝0．9958。方法回收率95．4％～98．1％，RSD＜4．63％。　用该分析方法测定了家兔口服尼群地平2h后在主要脏器体液中的分布。     

高效焊条的特点与经济性

使用高熔敷率的药皮焊条能达到成本低和生产效益高的目的。文中对高效焊条的优点和使用时的某些限制作了叙述。