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1.
人参中皂苷类化合物的HPLC-ESI MS研究   总被引:9,自引:0,他引:9  
利用高效液相色谱与电喷雾质谱联用技术分析鉴定了人参粗提物中人参皂苷类化合物。实验采用反相C18色谱柱,二元线性梯度洗脱(0.2%的醋酸水溶液和乙腈),分离并检测了人参中的皂苷类化合物:通过与电喷雾质谱的联用和质谱的源内CID技术获得了其中主要色谱峰相对应化合物的相对分子质量和结构信息。  相似文献   

2.
非水溶液毛细管电泳   总被引:6,自引:0,他引:6  
王荣英  辛慧君 《分析化学》1997,25(10):1228-1231
评述了非水溶液毛细管电泳的应用及发展,对非水溶液毛细管电泳的原理及应用情况作了简要叙述,有机试剂在毛细管电泳中的加入,扩大了分析物质的范围,以纯有机试剂作电泳介质,具有许多水溶液毛细管电不能比拟的优点。  相似文献   

3.
采用高效液相色谱-电喷雾式检测器分离分析聚羧酸系减水剂的大单体组分-脂肪醇聚氧乙烯基醚类。以Agilent ZORBAX SB-C8柱为分离柱,甲醇-水溶液为流动相进行梯度洗脱,采用电喷雾式检测器。在优化的色谱条件下,样品各组分间分离效果良好。高效液相色谱-质谱联用分析结果表明,各组分依据大单体中EO加合数的不同进行分离。  相似文献   

4.
传统的离子色谱主要应用于水溶液中的阴、阳离子和极性化合物。随着离子色谱应用范围的扩大,通过合适的样品制备,将非水溶液的样品转化为水溶液,包括有机溶剂、固体样品和气态样品,特别是随着我们对大气环境、气体纯度以及呼出气体中气态样品的组成等方面的重视,越来越多的气体和气态样品,特别是离子态和极性化合物,可通过合适的样品制备、采集转化为水溶液,通过离子色谱技术进行分析。综述了气体组分的离子色谱检测技术,总结了气体样品、气溶胶以及液态样品中气体物质的制备和采集方法,运用离子色谱技术对上述样品进行测定,并对该技术运用过程中存在的问题及发展前景进行了展望。  相似文献   

5.
刘宇平  文大为  陈政  廖一平  刘虎威 《色谱》2004,22(6):583-588
应用高效液相色谱(HPLC)及液相色谱-电喷雾离子化质谱(LC-ESI-MS)方法对反式白藜芦醇的长期热稳定性及光致顺反异构化反应进行了研究。色谱条件为:采用Hypersil-ODS色谱柱分离,流动相为甲醇-0.05%三氟乙酸水溶液(体积比为60∶40)(用于HPLC分析)及甲醇-5 mmol/L甲酸铵水溶液(含0.1%甲酸)(体积比为60∶40)(用于LC-ESI-MS分析),检测波长300 nm,进样量20 μL(HPLC)或10 μL(LC-ESI-MS);质谱检测中设定为负离子模式。在4~40  相似文献   

6.
硅胶是最常用的色谱固定相填料.毛细管电色谱(CEC)广泛地使用反相硅胶填料分离中性和非极性物质.极性和碱性物质由于在反相填料上色谱保留很小或不保留,对这些物质的分离长期以来一直是毛细管电色谱反相分离模式的挑战~([1,2]).  相似文献   

7.
本文采用高效液相色谱与电喷雾质谱联用技术在线分析鉴定了车前草提取物中的三种苯乙醇苷化合物。实验采用反相C18色谱柱,0.2%的醋酸水溶液和乙腈梯度洗脱,车前草中的苯乙醇苷化合物得到很好的分离。在电喷雾质谱负离子条件下,获得了三种苯乙醇苷化合物的分子离子峰,分子量信息,进一步通过质谱的源内CID技术得到相应化合物的结构信息。通过得到的这些信息与文献中的已知化合物或标准品对照从而推断出化合物的结构。  相似文献   

8.
毛细管电色谱柱重复性考察及实验条件的选择   总被引:4,自引:1,他引:3  
施维  张丽华  董礼孚  邹汉法  张玉奎 《色谱》1997,15(3):201-203
成功地研制了75μm内径偶联式和75,100μm内径非偶联式毛细管电色谱柱。在自制电色谱柱上获得了小于2.12%的保留时间RSD值,考察了pH值、有机溶剂浓度对保留行为的影响,并用以指导实验条件的选择。比较了两种方式电色谱柱的峰形。  相似文献   

9.
薄海波 《色谱》2011,29(2):180-183
建立了水果、蔬菜、豆类和粮谷中百草枯残留的高效液相色谱-串联质谱(HPLC-MS/MS)分析方法.用水提取样品中的百草枯,弱阳离子交换(WCX)固相萃取柱(SPE)净化.采用CAPCELL PAK ST色谱柱(150 mm×2.0mm).乙腈-10 mmol/L乙酸铵水溶液(用甲酸调至pH 4.0)为流动相,以电喷雾离...  相似文献   

10.
非水胶束电动色谱分离邻苯二甲酸酯类化合物   总被引:2,自引:0,他引:2  
非水胶束电动色谱(NAMEKC)兼具非水毛细管电泳的优点和胶束电动色谱的分离机制,尤其适于对强疏水性化合物进行分离分析。在以甲酰胺为非水溶剂的电泳介质中,采用十二烷基硫酸钠(SDS)形成胶束相,开展NAMEKC方法的研究。通过添加水溶液、调节水溶液酸度、添加有机溶剂、改变SDS浓度等操作条件的考察,在15 min 内实现了3种美国环保局优先监测的污染物——邻苯二甲酸二甲酯、邻苯二甲酸二乙酯、邻苯二甲酸二丁酯的分离。分离度最小者为1.5,检测限优于3.04 mmol/L(以信噪比为3计)。3种典型的强疏水性物质的成功分离,显示出NAMEKC方法在分离疏水性物质方面的优势,扩展了NAMEKC在电中性有机物分析中的应用。  相似文献   

11.
This review summarizes applications of CEC for the analysis of proteins and peptides. This "hybrid" technique is useful for the analysis of a broad spectrum of proteins and peptides and is a complementary approach to liquid chromatographic and capillary electrophoretic analysis. All modes of CEC are described--granular packed columns, monolithic stationary phases as well as open-tubular CEC. Attention is also paid to pressurized CEC and the chip-based platform.  相似文献   

12.
Capillary electrochromatography of peptides and proteins   总被引:1,自引:0,他引:1  
Li Y  Xiang R  Wilkins JA  Horváth C 《Electrophoresis》2004,25(14):2242-2256
This paper reviews recent progress in bioanalysis using capillary electrochromatography (CEC), especially in the field of separation of proteins and peptides. Fundamentals of CEC are briefly discussed. Since most of the recent developments on CEC have focused on column technology, i.e., design of new stationary phases and development of new column configurations, we describe here a variety of column architectures along with their advantages and disadvantages. Newly emerged column technologies in CEC for high speed and high efficiency separation are also discussed. Different analytical platforms of CEC such as pressure-assisted CEC or voltage-assisted micro- high-performance liquid chromatography (HPLC), CEC with different detection techniques, CEC on microchip platforms and multidimensional electrochromatography with their applications in peptide and protein analysis are presented.  相似文献   

13.
Zou H  Ye M 《Electrophoresis》2000,21(18):4073-4095
Adsorption is always considered a troublesome effect in capillary electrophoresis (CE) and capillary electrochromatography (CEC). However, the adsorption effect can also be exploited to prepare or optimize the stationary phase in CEC. Compared with the chemical synthesis of new stationary phase materials for CEC, this method is simpler and more convenient. This review is focused on CEC with physically and dynamically adsorbed stationary phases. Separation of some acidic, basic and neutral solutes as well as enantiomers in CEC with dynamically adsorbed stationary phases are presented. The theory for the migration of charged solutes and the stationary phases currently used in CEC are also briefly reviewed.  相似文献   

14.
Capillary electroendoosmotic chromatography of peptides   总被引:1,自引:0,他引:1  
This review focuses on the current state of peptide separation by capillary electroendoosmotic chromatography (CEC). When carried out under optimised conditions, peptide separation by CEC methods represents an orthogonal and complementary technique to micro-HPLC (micro-HPLC) and high-performance capillary zone electrophoresis (HPCZE). The origin of the selectivity differences that can be achieved with these three separation techniques (CEC, micro-HPLC and HPCZE), respectively are discussed, and the current limits of performance with CEC methods documented. Peptide separations by CEC methods with n-alkyl bonded silicas or mixed-mode phases are also illustrated. The development of different variants of CEC and pressurised CEC (also commonly referred to in the literature as electrically-assisted micro-HPLC) are examined. The potential of coupling CEC systems to mass spectrometers for real-time analyses of peptides or protein digests has been examined. Several future directions for the application of this technique in phenotype/proteomic and zeomic mapping of naturally occurring peptides and proteins are highlighted.  相似文献   

15.
田耘  曹小敏  张琪  曾昭睿 《色谱》2009,27(6):737-744
超分子化学是一门研究分子间特定识别能力的新兴学科,超分子化合物所具有的主-客体识别能力为高选择性的色谱分离提供了广阔的发展前景。毛细管电色谱是近年来发展起来的一种高效、高选择性的微分离技术,电色谱固定相是该技术的核心部分,一直是研究的热点。本文综述了1998年以来环糊精、杯芳烃、冠醚以及大环多胺等4种超分子化合物用作毛细管电色谱固定相的研究进展情况。  相似文献   

16.
Gübitz G  Schmid MG 《Electrophoresis》2004,25(23-24):3981-3996
This review summarizes recent developments in chiral separation in capillary zone electrophoresis (CZE), electrokinetic chromatography (EKC), and capillary electrochromatography (CEC) covering literature published since the year 2000. New chiral selectors and innovative approaches for CE and CEC are introduced. Recent progress in column technology for CEC is highlighted and the development of new chiral stationary phases is discussed. This review is not dedicated to list applications but will focus on new developments.  相似文献   

17.
磁场辅助毛细管电色谱是液相色谱研究领域中出现的新技术.它利用外加磁场的引力将置于毛细管内的具有磁响应性的硅胶微球或四氧化三铁微球固定在管内任意位置.磁场固定微球聚集体既可用作填充柱,直接用于电色谱分离;也可用作柱筛,用于填装由商品色谱填料组成的色谱柱.这一技术的优势在于制备简便易行,柱管可以再生使用,适合于微流控芯片上柱筛或柱床的制作.本文简要评述磁场辅助毛细管电色谱的进展,包括磁性色谱填料的制备,磁场固定柱床电色谱,磁性柱筛电色谱及毛细管柱内柱结构参数的测定等方面.  相似文献   

18.
毛细管电色谱技术研究进展   总被引:3,自引:0,他引:3  
毛细管电色谱是一种新型的微分离技术,它结合了毛细管电泳和高效液相色谱的优点,近年来越来越受到分析化学家的关注。本文介绍了近几年来毛细管电色谱技术取得的最新进展,包括填充柱、开管柱、整体柱电色谱的色谱柱制备技术,压力驱动电色谱技术,毛细管电色谱的检测技术及样品预富集技术,指出了存在的问题并展望了电色谱发展前景。  相似文献   

19.
Capillary electrochromatography (CEC) is an emerging technique that combines features of both micro-capillary high-performance liquid chromatography (microHPLC) and capillary electrophoresis (CE). This separation technique possesses high speed and the efficiency of an electro-driven system, while the selectivity and sample loadability compare to those of a packed capillary LC column. Since the separation mechanism is based on that of HPLC, the concept of isoeluotropic strength and selectivity of solvents as well as the on-column focusing techniques for sample introduction used in LC can be applied in CEC. This article examines some of these features of CEC in the context of our own experiences with the technique. More specifically, emphasis is placed on applications of CEC to the analysis of DNA adducts of polyaromatic hydrocarbons by coupling CEC to mass spectrometry. It is shown that, with proper selection of mixed organic modifiers in the mobile phase, i.e. ternary and quaternary mobile phases, complex DNA adduct mixtures derived from in vitro reactions can be separated isocratically with improved selectivity and much greater speed than by HPLC. Additionally, the speed of the analysis is further enhanced by employing a step gradient. Furthermore, CEC may be easily coupled to mass spectrometry such that the characterization of each isolated component from the mixtures is performed on-line with the separation. By using on-column focusing, the sample loadability onto a CEC column is improved.  相似文献   

20.
Retention behaviour of biological peptides was investigated on a stationary phase bearing an embedded quaternary ammonium group in a C21 alkyl chain by both high-performance liquid chromatography (HPLC) and capillary electrochromatography (CEC). In HPLC experiments, variation of acetonitrile (ACN) content in the mobile phase showed that peptides are mainly separated by RP mechanism. The weak or negative retention factors observed as compared to C18 silica stationary phase suggested the involvement of an electrostatic repulsion phenomenon in acidic conditions. Comparison of HPLC and CEC studies indicated that (i) ion-exclusion phenomenon is more pronounced in HPLC and (ii) higher ACN percentage in mobile phase induce for some peptides an increase of retention in CEC, pointing out the existence of mechanisms of retention other than partitioning mainly involved in chromatographic process. This comparative study demonstrated the critical role of electric field on peptide retention in CEC and supports the solvatation model of hydrolytic pillow proposed by Szumski and Buszewski for CEC using mixed mode stationary phase in CEC.  相似文献   

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