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毛细管电色谱(CEC)因兼具高效液相色谱(HPLC)的高选择性和毛细管电泳(CE)的高分离效率而受到越来越多研究者的关注。在毛细管电色谱中,选择合适的固定相材料对获得优异的分离效果起着十分重要的作用。近年来,多种新型材料如氧化石墨烯、蛋白质、金属有机框架(MOFs)及共价有机框架(COFs)等被作为固定相应用于毛细管电色谱领域以期获得更好的分离性能,同时拓展毛细管电色谱的应用范围。其中,COFs因具有孔隙率高、比表面积大、高稳定性、孔径可调和可设计性强等独特性质,在毛细管电色谱领域显示出了巨大的应用前景。鉴于此,本文对2016-2023年间COFs在毛细管电色谱领域的研究进展进行了综述,包括COFs毛细管电色谱柱的分类和制备方法,以及基于COFs固定相的毛细管电色谱技术在环境内分泌干扰物、农药、芳香族化合物、氨基酸及药物分离领域中的应用及分离机理等内容。最后对发展基于COFs固定相的毛细管电色谱应努力解决的问题和该技术未来的发展方向进行了分析和展望。 相似文献
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毛细管电色谱技术(CEC)是一种集微柱液相色谱的高选择性、多样性及高效毛细管电泳(HPCE)的高效性、高分辩率为一体的新的电泳分离技术。本文介绍了毛细管电色谱的历史、发展及研究现状;并对电色谱的基本理论与技术作了阐述。 相似文献
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毛细管电色谱是在毛细管中依靠电渗流来驱动流动相 ,同时溶质与固定相发生相互作用的一种色谱分离模式 ,它有高效液相色谱的高选择性 ,同时兼具毛细管电泳的高效性 [1] .传统电色谱柱是将HPLC填料装入毛细管 ,但由于装柱困难且易产生气泡而在一定程度上阻碍了电色谱的发展 [2~ 4 ] .通过柱内合成的方法直接在毛细管中制成连续床毛细管电色谱柱 ,可避免两端烧塞 . 1 995年 Svec等 [5,6]首次将连续床层色谱柱用于毛细管电色谱 ,此后 ,有关毛细管中原位合成连续床电色谱柱的方法得到了应用 [7~ 11] .为了使原位合成电色谱柱能产生电渗流 ,… 相似文献
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Introduction Capillary electrochromatography(CEC) is a hybrid technique that couples the good selectivity of high-performance liquid chromatography(HPLC) and the high separation efficiency of capillary electrophoresis(CE).Both charged and uncharged compou… 相似文献
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One of the reasons for the immense interest in capillary electrochromatography (CEC) is its feature to combine chromatographic selectivity with the high efficiency and the miniaturization potential of capillary electrophoresis (CE). The capability of commercial CE instruments to run CEC has enforced the readiness of users and researchers to work on this separation technique. Nevertheless, to fully exploit the potential of CEC, a routine CE device can certainly not fulfill all requirements. Two different approaches have been made to overcome this problem. The first was to modify commercial CE instruments for various demands. Pressurization of the packed capillary to prevent "air" bubble formation, gradient elution capabilities and thermostating devices allowing a greater flexibility in column designs have been implemented in CE instruments of several manufacturers. A completely different approach is the development of modular laboratory-made instrumentation dedicated to special CEC requirements. In order to increase mobile phase velocity and thus the speed of analysis the availability of voltages higher than 30 kV was accomplished in some of these devices. Gradient elution was achieved by either coupling of gradient LC systems or an electroosmotic generation of the changing eluent composition. When a pressure gradient is applied between both column ends in addition to the voltage gradient, a hybrid between capillary HPLC and CEC results. This chromatographic mode is named pressure-assisted electrochromatography (PEC). Either CE instruments equipped with additional HPLC pumps or modular laboratory-made devices are suitable for PEC. In CEC, sensitivity for UV detection is rather poor due to the short optical path length for on-column detection in capillary separation techniques. A special cell design with enhanced light path is presented and further principles like, e.g., fluorescence detection and coupling to mass spectrometry are discussed. 相似文献
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毛细管电色谱和加压毛细管电色谱的进展与应用 总被引:2,自引:1,他引:1
毛细管电色谱(CEC)以内含色谱固定相的毛细管为分离柱,以电渗流为驱动力,既可以分离带电物质也可以分离中性物质。它结合了毛细管电泳和高效液相色谱两者的优点,兼具高柱效、高分辨率、高选择性和高峰容量的特点,同时具有色谱和电泳的双重分离机理。然而,“纯粹”的电色谱在实际应用中有着天然的弱点,即: 在电流通过毛细管柱中的流动相时容易产生气泡(焦耳热作用),从而使电流中断和电渗流停止,毛细管柱必须被重新用流动相润湿后方能再次使用。加压毛细管电色谱(pCEC)将液相色谱中的压力流引入CEC系统中,不仅解决了气泡、干柱等问题,而且实现了定量阀进样和二元梯度洗脱。CEC和pCEC作为微分离领域的两种前沿技术,满足了当前复杂样品分析和分析仪器微型化的需求,近年来获得了广泛的关注。本文综述了这两种技术近来的发展,包括仪器、色谱固定相的发展,总结了其在生命科学、药物分析、食品安全以及环保样品分析等方面的应用进展,评述了各方法的特点,并展望了CEC和pCEC今后的发展和应用前景。 相似文献
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Kiyokatsu JinnoHirokazu Sawada 《Trends in analytical chemistry : TRAC》2000,19(11):664-675
Capillary electrochromatography (CEC), which combines the advantages of the high efficiency of capillary electrophoresis (CE) and the high selectivity of liquid chromatography (LC), has recently received considerable attention. Most CEC experiments have been performed with capillary columns packed with small LC packing materials (1.5–5 μm particle diameter). However, problems such as difficulties in packing the small LC packing materials and fabricating the frits still exist in preparing the CEC column. The use of open-tubular columns in CEC is therefore an alternative approach that can eliminate the problems encountered in packed-column CEC. So far, several types of open-tubular columns have been proposed for CEC separations and in this article recent progress in this area is reviewed. 相似文献
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毛细管电色谱具有高分离效率、多种保留机制和高选择性的优点。近年来,利用毛细管电色谱进行对映异构体的手性拆分受到了广泛关注。相对于传统的填充柱和开管柱,整体柱在手性拆分方面具有显著优势。与手性硅基整体柱相似,手性有机聚合物整体柱由于具有大孔,可产生较高的流速而压降较小。该文综述了近十年手性有机聚合物整体柱制备方法的研究进展,将手性有机聚合物整体柱的制备方法分为"原位聚合法"和"手性修饰法"两种,虽然前者制备简单并广泛应用于早期研究,但聚合混合液成分的微小改变即可引起最终聚合物的形态变化,并且大部分带丙烯基的手性选择剂较难从市场购买。因此,手性修饰法因作为手性选择剂基质的整体柱制备且优化只需进行一次的优势而受到普遍关注。亲核取代、杂环开环和点击化学是常用的修饰手段。该文总结了这两种制备方法的应用,同时对未来的研究方向提出参考性意见。 相似文献
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毛细管电泳和毛细管电色谱技术在农药残留检测中的应用 总被引:7,自引:2,他引:5
由于毛细管电泳(CE)和毛细管电色谱(CEC)具有所需样品体积小、分离效率高等特点,越来越多的学者已将它们应用到农药残留(简称农残)检测中,并将它们同各种不同的检测器以及样品浓缩方法相结合,以提高检测的灵敏度。本文对CE和CEC两种方法中所涉及的常见的样品预浓缩方法进行了简要的介绍。对各种不同类型的检测器(如紫外检测、荧光检测、电化学检测以及质谱检测等)的优缺点及其在农残检测中的应用情况进行了评述;同时对手性农药的CE和CEC分离检测情况进行了特别介绍;并对CE和CEC在农残分析与检测中的应用前景进行了展望。 相似文献
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Enantiomers of bioactive molecules often differ in potency, toxicity, metabolism, and pharmacological actions. Capillary electrochromatography (CEC) is an emerging separation technique being investigated for use in chiral separations. CEC is a hybrid of HPLC and CE. CEC combines the electrophoretic mobility of CE with the partitioning mechanisms of HPLC. In this overview, several resolution mechanisms commonly used in CEC and the main parameters influencing the selectivity of the chiral separation will be discussed. Current applications of CEC in chiral separations of pharmaceuticals will be provided for each type of resolution mechanism. Finally, the advantages and limitations of CEC will be described, followed by the future outlook for CEC. 相似文献