高效液相色谱法测定注射用氢化可的松琥珀酸钠含量的色谱条件考察

筛选高效液相色谱法测定注射用氢化可的松琥珀酸钠含量的适合的色谱条件。通过改变色谱条件,对注射用氢化可的松琥珀酸钠含量测定的各种常用的色谱系统进行对比研究,筛选出适宜的色谱条件为:Kromasil 100-5C18柱(4.6×1 50mm,5μn)为色谱柱;流动相为甲醇-磷酸盐缓冲液(50:50);流速:0.5mL/min;检测波长:242nm。该色谱条件下注射用氢化可的松琥珀酸钠测定方法的系统适用性较好,可用于其含量测定。     

中药羌活HPLC-荧光指纹谱研究

建立不同来源羌活的高效液相-荧光检测指纹谱,为提高羌活药材质量控制水平提供参考。色谱柱:MetachemODS-C18;流动相:乙腈-0.025mol/L磷酸水溶液(45:55),荧光检测条件:λEx=310nm、λEm=480nm;采用聚类分析法进行分析比较。得到20个共有指纹色谱峰,确定了基准样本色谱峰的相对保留时间和相对峰面积,各羌活样品与基准样本相似度值均在0.8以上,构建羌活的高效液相-荧光指纹图谱质控方法。本试验所确定HPLC-荧光光谱的指纹图谱质控方法灵敏度高,稳定性、重现性良好,可作为羌活药材的质量评价依据。     

反相高效液相色谱法测定合成产物2-硝基芴酮的含量

建立了一种反相高效液相色谱法测定2-硝基芴酮含量的方法。液相色谱条件为:EliteHypersil ODS2C18色谱柱(4.6mm×250mmi.d.,5μm),甲醇-四氢呋喃-水为流动相(体积比为65∶15∶35)。在流速1.0mL/min,检测波长254nm,柱温25℃条件下,产物2-硝基芴酮与原料芴酮、副产物2,7-二硝基芴酮在2-硝基芴酮浓度为5—30mg/L范围内分离效果良好,峰面积与质量浓度呈良好的线性关系,相关系数为0.9985;平均回收率值大于99.00%,相对标准偏差小于1.00%。结果表明,该方法具有操作简便、精密度和准确性高的特点,可适用于工业生产2-硝基芴酮含量的测定。     

HPLC-DAD法测定辣椒及其制品中苏丹红的含量

建立了应用高效液相色谱测定辣椒粉及其少量含油制品中的苏丹红Ⅰ、Ⅱ、Ⅲ、Ⅳ含量的检测方法.采用Symmetry C18反相色谱柱(3.9mm×150mm,5μm),流动相为乙腈醋酸溶液(V乙磷:Vo.1%醋酸＝7∶1),等度洗脱,流速1.0mL/min;柱温30℃;检测波长230nm.在选定色谱条件下,苏丹红Ⅰ、Ⅱ、Ⅲ、...     

高效液相色谱法测定血清中二氯乙酸钠的浓度

用高效液相色谱法测定了家兔血清中二氯乙酸钠的含量。二氯乙酸钠(DCA-Na)在碱性条件下与水合肼定量生成稳定的腙,以IPR-B8为色谱试剂,在Zorbax ODS(4.8mm×250mm)柱上,以水-甲醇-IPR-B8为流动相进行分离,结果分离灵敏度为0.05AUFS,在268nm处,衍生物线性范围0.65—50.0μg/mL,r=0.9995,回收率98.5±3.3%。     

毛细管电色谱中进样时间对柱效的影响

毛细管电色谱是近年发展起来的一种新型微分离技术，它结合了高效液相色谱和毛细管电泳的物点，具有高效、快速，高选择性，其有关理论研究和应用越来越深入，本文从色谱动力学角度讨论了毛细管电色谱中进样时间对柱的影响。     

高效液相色谱法测定油炸南瓜饼中的丙烯酰胺

建立了一种利用高效液相色谱法测定油炸南瓜饼中丙烯酰胺含量的方法。样品经正己烷脱脂后用水作提取剂,提取液经高速离心处理后,上层清液用自制中性氧化铝小柱净化,高效液相色谱法测定,色谱条件：流动相为水;流速0.6mL/min;进样量5μL;保留时间6.6min;检测波长199.1nm;柱温30℃。方法的检出限为0.001μg/mL,回收率在87.50%—94.11%之间,相对标准偏差低于5%（n=6）。     

高分离度快速液相色谱法测定牛黄解毒片中黄芩苷的含量

采用高分离度快速液相色谱(RRLC)测定牛黄解毒片中黄芩苷的含量。色谱柱为Zorbax XDB-C18(4.6×50mm,1.8μm),流动相为甲醇-水-磷酸(45∶55∶0.2),检测波长315nm,流速0.5mL.min-1,柱温为30℃。黄芩苷在0.15—1.35μg(r=0.9999)范围内峰面积与浓度呈良好的线性关系,加样回收率为100.41%,RSD=1.42%。采用高分离度快速液相色谱(RRLC)测定复方牛黄解毒片中黄芩苷的含量,缩短了保留时间,提高了效率,降低了成本。本方法简便、准确,结果稳定。     

反相高效液相色谱法检测降血压肽

实验研究并建立了反相高效液相色谱(RP-HPLC)法检测降血压肽。结果表明:在选定的实验条件下,降血压肽浓度与抑制率呈良好的线性关系,校准曲线的相关系数为0.9936。测定的平均回收率98.6%—102.3%,相对标准偏差为2.63%,该方法简便、快速、准确、灵敏,可用于检测降血压肽。     

高效液相色谱-光电二极管陈列检测器联用检测不同产地荆芥中乌索酸和齐墩果酸

建立反相高效液相色谱-光电二极管联用法同时测定了荆芥中乌索酸和齐墩果酸的含量.色谱柱为Kromasil C18柱(250mm×4.6mm,5μm),流动相为甲醇-水(86∶14),流速0.8mL·min-1,光电二极管阵列检测器(PAD),检测波长210nm,柱温25℃.在选定色谱条件下线性范围良好,乌索酸和齐墩果酸的样品加样回收率分别为98.6%和99.2%,RSD为1.1%和1.9%.方法简便,分离效果好,可用于荆芥中乌索酸和齐墩果酸含量的测定.     

Multidimensional chromatography coupled with mass spectrometry for target-based screening

Summary The synthesis of structural analogs and the process of drug discovery have evolved dramatically through recent advances in solid-phase synthesis reagents and automated screening systems. As molecular diversity strategies emerge, the need for automated target-based selection of lead candidates becomes equally important. Multidimensional automated chromatographic techniques coupled to electrospray ionization mass spectrometry facilitate the selection process and provide maximum characterization information in a single screening run. The capture of tightly bound affinity leads by target biomolecules, followed by subsequent release and high-resolution separation with sensitive detection, significantly reduces the time required to identify and characterize lead compounds. This automated multidimensional chromatographic approach coupled with mass spectrometry, Selectronics, was used with several organic and natural libraries to demonstrate an automated target-based screening technique to select for high-affinity binders as potential lead compounds.Abbreviations ESI electrospray ionization - HPLC high-performance liquid chromatography - HTS high-throughput screening - ESI-TOF electrospray ionization time-of-flight - SAR structure-activity relationship     

微柱高效液相色谱与火焰光度检测器池用的初步研究

本文研究了常规高效液相色谱（ＨＰＬＣ）及微柱高效液相色谱（Ｍｉｃｒｏ－Ｃｏｌｕｍｎ ＨＰＬＣ）与气相色谱火焰光度检测器（ＦＰＤ）的联用技术及其应用。丁基锡等化合物经ＨＰＬＣ分离后,流出液通过ＦＰＤ进行特效检测。接口采用将毛细管直接引入燃烧头的方式。文中对各有关参数进行了选择、优化和讨论,对ＦＰＤ作为ＨＰＬＣ的在线检测器的呆能性作了初步探讨。     

Determination of natural aromatic acids using supercritical fluid chromatography

Derivatives of benzoic and cinnamic acids are secondary metabolites of plants, widely distributed in nature and possessing biological activity. Supercritical fluid chromatography (SFC) is shown to provide a high performance separation of nine most important representatives of this class of compounds with selectivity, dramatically different from the reversed-phase high-performance liquid chromatography. The retention and chromatographic separation parameters of analytes for four stationary phases of different nature are compared and the effect of supercritical fluid parameters and the composition of the mobile phase onto the chromatographic separation are analyzed. The optimal separation is found to be achieved when using a silica-based sorbent with 2-ethylpyridinium linked groups. The proposed approach for determination of the above-mentioned compounds is based on the combination of chromatographic separation with multiwavelength spectrophotometric detection and provides the detection limits in the range of 13.0–51.3 μg/L and the analysis duration about 2.5 min. The approach is successfully tested on real objects, such as different kinds of wine.     

黄酮类化合物色谱和光谱分析研究进展

简述了近年来国内外黄酮类化合物色谱和光谱分析方法,主要介绍了高速逆流色谱、胶束电动毛细管色谱、微乳薄层色谱、高效液相色谱、配位色谱分析法以及紫外光谱、荧光光谱、近红外光谱、三波长-光谱分析法.     

Thermal Lens Spectrometric Detection in Flow Injection Analysis and Separation Techniques

Abstract

Recent applications of thermal lens spectrometry in liquid chromatography (HPLC, ion chromatography), capillary electrophoresis, and flow injection analysis are reviewed. Possible effects of performing TLS measurements in flows are discussed initially for different TLS configurations. The emphasis is given to the analysis of real samples, and the performances of various detection schemes in combination with chromatographic techniques and FIA are discussed particularly in terms of sensitivity, sample throughput, and eventual interferences from complex matrices. Coaxial TLS detection with continuous wave excitation is most suitable for detection in HPLC, ion chromatography, and FIA using long‐path length cells, when large volume samples are available. On the other hand, transverse or crossed beam TLS was found most suitable for detection in CE where it provides low absolute LODs, which are lowered even further by thermal lens microscopy on microchips, where the capability of detecting a single molecule in the detection volume was demonstrated.     

Imaging of the chromatographic process

This paper describes a new application of NMR imaging in material science. It shows that MRI is able to provide information in liquid chromatography inaccessible by existing investigation methods. Density gradients, wetting status, inner voids, cracks, and channels in chromatographic columns can be visualized and quantified noninvasively for the first time. Due to the lack of a method permitting real-time analysis of band profiles, most information about chromatographic performance and dynamics has been hitherto derived from postseparation analysis. We demonstrate that fast imaging techniques can allow the visualization of band shapes on the fly, even at the high velocities encountered under high-pressure conditions. Sodium imaging provides information on special kinds of chromatography. We believe that the method has high potential for further development.     

模拟移动床色谱法纯化白藜芦醇

采用三带模拟移动床色谱法纯化虎杖白藜芦醇。实验结果表明:模拟移动床色谱纯化白藜芦醇的工艺参数为:流动相为V(甲醇):V(水):1:1;4根IDL=10mm×200mm ODS制备柱;柱连接方式1-2-1;洗脱带流量1.0mL/min,精制带流量1.5mL/min,吸附带流量1.6mL/min,进样流量0.1mL/min,切换时间19min。     

High Throughput Analysis and Purification in Support of Automated Parallel Synthesis

Rapid reverse-phase analytical and preparative HPLC methods havebeen developed for application to parallel synthesis libraries.Gradient methods, short columns, and high flow rates allowanalysis of over 300 compounds per day on a single system, orpurification of up to 200 compounds per day on a singlepreparative system. Hardware and software modifications allowcontinuous unattended use for maximum efficiency and throughput.     

Fragmentation of oxime and silyl oxime ether odd-electron positive ions by the McLafferty rearrangement: new insights on structural factors that promote α,β fragmentation

The McLafferty rearrangement is an extensively studied fragmentation reaction for the odd-electron positive ions from a diverse range of functional groups and molecules. Here, we present experimental and theoretical results of 12 model compounds that were synthesized and investigated by GC-TOF MS and density functional theory calculations. These compounds consisted of three main groups: carbonyls, oximes and silyl oxime ethers. In all electron ionization mass spectra, the fragment ions that could be attributed to the occurrence of a McLafferty rearrangement were observed. For t-butyldimethylsilyl oxime ethers with oxygen in a β-position, the McLafferty rearrangement was accompanied by loss of the t-butyl radical. The various mass spectra showed that the McLafferty rearrangement is relatively enhanced compared with other primary fragmentation reactions by the following factors: oxime versus carbonyl, oxygen versus methylene at the β-position and ketone versus aldehyde. Calculations predict that the stepwise mechanism is favored over the concerted mechanism for all but one compound. For carbonyl compounds, C-C bond breaking was the rate-determining step. However, for both the oximes and t-butyldimethylsilyl oxime ethers with oxygen at the β-position, the hydrogen transfer step was rate limiting, whereas with a CH(2) group at the β-position, the C-C bond breaking was again rate determining. n-Propoxy-acetaldehyde, bearing an oxygen atom at the β-position, is the only case that was predicted to proceed through a concerted mechanism. The synthesized oximes exist as both the (E)- and (Z)-isomers, and these were separable by GC. In the mass spectra of the two isomers, fragment ions that were generated by the McLafferty rearrangement were observed. Finally, fragment ions corresponding to the McLafferty reverse charge rearrangement were observed for all compounds at varying relative ion intensities compared with the conventional McLafferty rearrangement.     

X‐ray absorption and x‐ray fluorescence for the characterization of titanium oxide‐modified HPLC silicas

Titanium oxide grafted on to the surfaces of chromatographic silica was investigated by x‐ray fluorescence (XRF) and x‐ray absorption (XAS) spectroscopy and the latter used before and after the extensive use of this material as a support for reversed‐phase high‐performance liquid chromatography (RP‐HPLC). XRF indicated the formation of a complete 2:1 monolayer whereas XAS suggested the presence of more than one titanium oxide structure. These structures show some slight modification after immobilization of PMOS and use in HPLC. Copyright © 2005 John Wiley & Sons, Ltd.