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毛细管硅胶基质整体柱的制备及其电色谱性能研究 总被引:3,自引:0,他引:3
采用热引发一步法制备了毛细管电色谱硅胶基质整体柱。通过使用表面活性剂(十二烷基磺酸钠)增加了反应液中两相之间的相互溶解,使得反应液最终成为均相溶液,实现了硅胶整体柱的均相聚合制备。所制备的均相硅胶整体柱内部结构更加均匀,大大提高了分离度。评价了该整体柱的电色谱性能,深入探讨了有机溶剂比例、pH值、电压以及温度等电色谱操作条件对电渗流、保留机理和柱效的影响。在该均相硅胶基质整体柱上成功地分离了9种中性物质(硫脲、苯、甲苯、乙基苯、正丙苯、萘、正丁基苯、芴和蒽)以及7种中性、酸性和碱性物质(硫脲、邻氨基酚、苯酚、苯、邻甲苯胺、α-萘胺和2,4-二氯苯胺)。该柱对硫脲的柱效超过110000塔板/m。 相似文献
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聚丙烯酸酯类毛细管整体柱的制备及其在加压毛细管电色谱中的应用 总被引:3,自引:0,他引:3
毛细管电色谱(CEC)是毛细管电泳(CE)和微径液相色谱(micro—HPLC)技术的结合,是集CE的电子迁移机制和micro-HPLC的分配分离机理发展起来的一种高效微分离技术.CEC以塞子流型的电渗流代替抛物线流型的压力流,具有CE的高效性,能够分离电中性化合物而具有HPLC的高选择性. 相似文献
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采用温和条件下的溶胶-凝胶技术,成功制备了阴离子交换-反相混合模式硅胶基质毛细管电色谱整体柱。通过调整反应液中不同前体的比例,优化了整体柱的制备条件。通过扫瞄电镜,对柱床进行了表征和分析。实验发现,所制备的整体柱电渗流的方向和大小可随流动相pH值的改变而改变,在酸性和中性条件下,具有从阴极流向阳极的电渗流;当流动相pH值升至约7.5时,电渗流方向发生了反转(由阳极流向阴极)。在优化的实验条件下,用所制备的整体柱对所考察的酸性(中性)化合物实现了快速分离,并获得了高达160,000N/m的柱效。 相似文献
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混合模式毛细管整体色谱柱由于保留机理多样,具有很好的应用前景。本文以[2-(甲基丙烯酰基氧基)乙基]二甲基-(3-磺酸丙基)氢氧化铵(SPE)为单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,偶氮二异丁腈(AIBN)为引发剂,正丙醇/1,4-丁二醇/水三元体系为致孔剂,制备了聚合物基质SPE-co-EDMA毛细管液相色谱整体柱。通过系统优化致孔剂和反应物种类和配比、引发剂的用量、反应时间和反应温度等因素,提高了整体柱的柱效、机械强度、渗透性和重复性。结果表明该毛细管整体柱在10 MPa内具有良好的机械强度,渗透性为2.17×10-14 m2,而且批次内和批次间峰面积的重现性(RSD)分别为1.0%和4.6%。以极性和非极性的多种化合物评价了该毛细管整体柱的色谱性能,结果表明该柱在高有机相中具有亲水相互作用机理,在低有机相中具有反相作用机理,显示出混合模式分离特性。 相似文献
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以十二烷基甲基丙烯酸酯(LMA)为功能单体,乙叉二甲基丙烯酸酯(EDMA)为交联剂,正丙醇、1,4-丁二醇和水为三元致孔剂,以及2-丙烯酰胺-2-甲基丙磺酸(AMPS)为电渗流产生剂,制备了聚十二烷基甲基丙烯酸酯整体柱。系统考察了AMPS含量和单体-致孔剂比例对柱性能的影响。结果表明,单体溶液和致孔剂的最佳聚合溶液质量比为35:65,其中单体溶液组成为59.5%(质量分数,下同)LMA、40%EDMA和0.5%AMPS,致孔剂溶液组成为60%正丙醇、30%1,4-丁二醇和10%水。在优化的流动相条件下应用制备的整体柱采用毛细管电色谱法成功地分离了肌红蛋白酶解产物。 相似文献
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The classification and regression trees (CART) possess the advantage of being able to handle large data sets and yield readily interpretable models. A conventional method of building a regression tree is recursive partitioning, which results in a good but not optimal tree. Ant colony system (ACS), which is a meta-heuristic algorithm and derived from the observation of real ants, can be used to overcome this problem. The purpose of this study was to explore the use of CART and its combination with ACS for modeling of melting points of a large variety of chemical compounds. Genetic algorithm (GA) operators (e.g., cross averring and mutation operators) were combined with ACS algorithm to select the best solution model. In addition, at each terminal node of the resulted tree, variable selection was done by ACS-GA algorithm to build an appropriate partial least squares (PLS) model. To test the ability of the resulted tree, a set of approximately 4173 structures and their melting points were used (3000 compounds as training set and 1173 as validation set). Further, an external test set containing of 277 drugs was used to validate the prediction ability of the tree. Comparison of the results obtained from both trees showed that the tree constructed by ACS-GA algorithm performs better than that produced by recursive partitioning procedure. 相似文献
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以丙烯酸、2-丙烯酰胺-2-甲基丙磺酸为功能单体,N,N′-亚甲基双丙烯酰胺为交联剂,正十二醇、1,4-丁二醇及二甲基亚砜为致孔剂,偶氮二异丁腈为引发剂,原位聚合制备了丙烯酰胺类强阳离子交换整体柱。考察了驱动电压、有机调节剂、盐浓度、pH值等对电渗流的影响。结果表明,电渗流与驱动电压的线性关系良好,相关系数为0.9981;有机调节剂乙腈对电渗流的影响除与流动相的黏度有关外,还与固定相的溶胀有关,当浓度低时,电渗流随乙腈浓度的增加有反常的下降趋势;随着磷酸盐浓度逐渐增加,电渗流降低,与理论相符;在pH值为3~9范围内,电渗流基本上保持恒定,体现了整体柱使用酸碱范围宽的优越性。在优化的实验条件下,采用毛细管电色谱法在此整体柱上成功分离了5种多肽,体现了该类整体柱在多肽分离研究中的优势,为进一步将其应用于蛋白质分离研究打下了基础。 相似文献
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A silica-based monolithic stationary phase with mixed-mode of reversed phase (RP) and weak anion-exchange (WAX) for capillary electrochromatography (CEC) has been prepared. The mixed-mode monolithic silica column was prepared using the sol–gel technique and followed by a post-modification with hexadecyltrimethoxysilane (HDTMS) and aminopropyltrimethoxysilane (APTMS). The amino groups on the surface of the stationary phase were used to generate a substantial anodic EOF as well as to provide electrostatic interaction sites for charged compounds at low pH. A cathodic EOF was observed at pH above 7.3 due to the full ionization of residual silanol groups and the suppression in the ionization of amino groups. A variety of analytes were used to evaluate the electrochromatographic characterization and column performance. The monolithic stationary phase exhibited RP chromatographic behavior toward neutral solutes. The model anionic solutes were separated by the mixed-mode mechanism, which comprised RP interaction, WAX, and electrophoresis. Symmetrical peaks can be obtained for basic solutes because positively charged amino groups can effectively minimize the adsorption of positively charged analytes to the stationary phase. 相似文献
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胃蛋白酶亲和有机聚合物毛细管整体柱的制备及性能考察 总被引:1,自引:0,他引:1
以热引发原位聚合方法制备了聚(甲基丙烯酸缩水甘油酯(glycidyl methacrylate,GMA)-乙二醇二甲基丙烯酸酯(ethyleneglycol dimethacrylate,EDMA))毛细管整体柱,对整体柱的性能进行了表征。结果表明,柱内部结构均匀、渗透性好;整体柱能够实现苯等中性小分子化合物的分离,具有反相色谱特征,重现性和稳定性良好。利用整体柱环氧基团的活性,采用间接法,以戊二醛为连接臂制备胃蛋白酶亲和手性整体柱。在毛细管电色谱模式下进行了柱分离性能研究,并对缓冲液pH值和运行电压等分离条件进行了考察。结果表明,亲和整体柱对4种碱性手性药物(奈福泮、氨氯地平、西酞普兰、扑尔敏)有拆分效果,奈福泮、氨氯地平、西酞普兰能达到基线分离。本文为蛋白质亲和毛细管电色谱整体柱的制备和应用提供了新的思路和方法。 相似文献
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采用甲基丙烯酸月桂酯为基础功能单体,乙二醇二甲基丙烯酸酯为交联剂,正十二醇、1,4-丁二醇及二甲基亚砜为致孔剂,在内径为75 μm的石英毛细管内制备了具有良好机械性能及化学稳定性的反相毛细管整体柱。考察了致孔剂的种类、比例以及交联剂在单体混合物中的比例对柱压和分离效果的影响;以单体15%、交联剂15%、致孔剂70%(均为质量分数)作为优化配方,在70 ℃条件下反应24 h;并对所合成的毛细管整体柱进行了电镜表征,测试了流速、柱长与柱压的关系。结果表明,毛细管整体柱的通透性良好,可通过延长柱长的方法提高分离效果。将所制备的毛细管整体柱装于纳升级高效液相色谱仪上进行牛血清白蛋白及血浆样本的胰蛋白酶酶切液的分离,获得了比较理想的分离效果。 相似文献
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Organic-silica hybrid monolithic columns have drawn more and more attention due to the ease of preparation and good mechanical stability in recent years. Many synthetic approaches have been developed and a variety of hybrid monolithic capillary columns have been prepared. The sol-gel process is well recognized in the fabrication of hybrid monolithic columns, which can be mainly classified as one-step, acid/base two-step procedures. The new approaches such as the "one-pot" and nano-scaled inorganic-organic hybrid reagent of polyhedral oligomeric silsesquioxane used as a cross-linker have also emerged for the preparation of hybrid monolithic columns. The applications of the organic-silica hybrid monolithic capillary columns for capillary electrochromatography, micro high-performance liquid chromatography, solid-phase micro-extraction and enzymatic reactor etc. are included in this review. 相似文献
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利用溶胶-凝胶法,经过烷氧基硅烷的水解、硅羟基的缩聚、凝胶化、陈化、中孔制备、干燥和表面修饰等步骤制备了全氟癸基修饰的毛细管硅胶整体柱。采用该整体柱对全氟辛烷磺酸(PFOS)进行萃取富集,考察其富集特性和效率,并与传统的C18毛细管硅胶整体柱进行对比。结果表明,全氟癸基修饰毛细管硅胶整体柱(15 cm×75μm)对PFOS具有更高的吸附量和更好的富集选择性,其平均吸附量可以达到75 ng;样品中PFOS的质量浓度为0.25 mg/L时,富集倍数平均可以达到29倍。此全氟癸基修饰毛细管硅胶整体柱对PFOS具有良好的萃取富集性能,可用于水质中痕量PFOS的萃取富集。 相似文献