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The performance of an integrated capillary electrophoresis system with a novel split-flow sample injection mechanism and special high sensitivity UV absorbance detector is described. Sample introduction into the capillary is accomplished with a standard HPLC-type microliter syringe. The injected sample is divided proportionally between the separation capillary and an adjustable splitvent. The volume of sample introduced into the capillary can be manipulated by varying the length or the i.d. of the splitvent tubing; or the volume of sample injected. Data are presented showing reproducibility of retention time, peak height, and peak area; minimum detectability; and operation at short UV wavelengths. 相似文献
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使用手性冠醚及手性柱的HPCE和HPLC法拆分伯胺类药物对映体的对比研究 总被引:3,自引:0,他引:3
报道了在缓冲液中添加 1 8-冠 - 6 -四甲酸 (1 8C6 H4 )的高效毛细管电泳法(HPCE)对 8个含氨基的药物进行拆分 ,低 p H值 (2 .0 6 )和较高浓度的 Tris缓冲液(2 0 mmol· L- 1)可加快手性分离。用手性柱 Crownpak CR(+)的高效液相色谱(HPLC)法对与前相同的 8个含氨基药物进行拆分 ,甲醇浓度增大 ,分离度 RS值有所减小。实验结果还表明 ,使用 HPCE法拆分的各物质 RS值大于使用 HPLC法拆分相应物质的 RS值。 相似文献
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综述了近10年来高效毛细管电泳在黄酮类分析中的应用.着重介绍了黄酮类化合物毛细管电泳的CZE与MEKC两种模式的分离情况,同时简要介绍了黄酮类的结构与其电泳迁移行为的关系. 相似文献
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自80年代末高效毛细管电泳(HPCE)引起广泛重视以来,经过短短5年的时间。它在理论、仪器以及应用技术方面都已取得了高速的发展,并正在走向成熟。本文作为HPCE详细综述的第二部分,介绍HPCE在技术和应用方法方面的进展。 相似文献
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用4种不同的样品前处理方法,即①磷酸二氢钠萃取法(SE)、②磷酸二氢钠萃取-固相萃取法(SE-SPE)、③基质固相分散萃取法(MSPDE)和④基质固相分散萃取-固相萃取法(MSPDE-SPE)对鸡肉样品做前处理,用高效毛细管电泳测定试液中青霉素、氨苄青霉素和阿莫西林等3种药物的残留量。回收试验和色谱分离结果表明:方法②用于高效毛细管电泳法同时测定鸡肉样品中3种青霉素类药物的样品前处理更为合适。方法的加标回收率在73.1%~95.9%之间,相对标准偏差(n=5)在2.9%~9.8%之间。 相似文献
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Hongji Liu Byung-Yun Cho Richard Strong Ira S. Krull Steven Cohen King C. Chan Haleem J. Issaq 《Analytica chimica acta》1999,400(1-3):181-209
Peptides and small proteins, of limited molecular weight (MW) can be derivatized with a 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (6-AQC) reagent, leading to a single capillary zone electrophoresis (CZE) peak, suggestive of a completely tagged product. The number of tags per molecule was demonstrated by matrix assisted, laser desorption, time-of-flight mass spectrometry (MALDI-TOFMS) studies. In CZE, these species have greatly improved plate count and peak shape, improved (lowered) detectabilities, and in general, improved identification properties in the CZE mode in high performance capillary electrophoresis (HPCE). The formation of what appears to be a single, homogeneously tagged product is a function of how the derivatizations are performed. Once these conditions are optimized, virtually all peptides and small proteins tested (limited MW) can form single, fully tagged products, with the desirable CZE properties. These derivatization approaches thus lead to products that perform and are detected much better in CZE than their precursors (native, untagged peptides). The determined plate counts for these tagged peptides were as high as 6 million plates/m, which was very reproducible, and 59–12,000 times higher than the untagged (native) molecules. The peak symmetry was also improved greatly. The limit of detection (LOD) of some tested 6-AQC tagged peptides were nine to 209 times improved (lower) with ultraviolet (UV) absorption detection, again as compared with that for the native species. The LOD could be further lowered via laser induced fluorescence (LIF) detection in CZE, especially when acetonitrile (ACN) containing buffers were used. 相似文献
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A simple and inexpensive high performance capillary electrophoresis (HPCE) was applied to separate five benzoic acid compounds simultaneously. The investigation was carried out by micellar electrokinetic capillary chromatography (MECC). To avoid a time‐consuming and tedious procedure, orthogonal experimental design OA9 (34) for separation experiments was applied to find the optimal conditions in terms of the resolution and analytical time. The best conditions for separation were obtained using a 20 mM borax and 30 mM sodium dodecyl sulfate (SDS) buffer (pH 9.8) containing 2 mM β‐CD and 4% methanol (v/v). Online UV detection was performed at 250 nm. A voltage of 16 kV was applied and the temperature was controlled at 25 °C. Injection was performed for 5 s. The method was validated for the quantification of benzoic acid, salicylic acid and ortho‐aminobenzoic acid in Radix Isatidis, a traditional plant medicine with removal of endotoxin. The separation and determination were satisfactory and quick. 相似文献