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高效毛细管电泳对农药手性拆分的进展 总被引:5,自引:0,他引:5
环境中使用的农药绝大多数都具有位置或光学异构体,而且同一农药的不同对映体通常也具有不同的药效和毒性,但是目前有关手性农药的研究还很少,高效毛细管电泳是一门特别适于手性分离研究的技术,综述了近年来利用高效毛细管电泳技术对手性农药进行拆分的研究,最后对该工作的发展前景进行了讨论。 相似文献
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建立了高效毛细管电泳拆分阿苯达唑亚砜对映体的方法,考察了背景电解质pH、环糊精种类和浓度,有机改性剂种类和浓度对分离的影响,对分离条件进行了优化。实验结果表明:在含36g/L磺化β-环糊精和10%甲醇的20mmol/L Tris-H3PO4(pH2.5)缓冲体系中,阿苯达唑亚砜对映体具有良好的分离效果。 相似文献
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高效毛细管电泳分离中的化学平衡 总被引:2,自引:0,他引:2
在高效毛细管电泳(HPCE)中缓冲对分离有重要影响,缓冲中的化学平衡决定了待测组分的存在状态或形态,从而决定了组分的电泳尚度,淌度的差异是HPCE分离之基础,因此,溶液化学平衡在HPCE分离中起着重要作用,本文综述了电泳淌度,HPCE分离与化学平衡的关系,并要介绍了电泳淌度与酸碱平衡,络合平衡的关系,从化学平衡的角度,讨论了酸碱性化合物,金属离子,对映异构体等几大类化合物的HPCE分离。 相似文献
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Particle‐loaded (3 μm, octadecylsilica) monolithic sol‐gel columns have been prepared and selected characteristics measured. Several electrical properties may be calculated from simple current measurements in the column as a whole. Resistivity in the packed segment is approximately three times that in open segments, resulting in a 60% increase in field strength in the packed regions compared to the capillary with no packing. The surprisingly high specific permeability of these sol‐gel columns is characteristic of 8‐μm particles, which allows their operation in the microLC mode at pressures as low as 69 kPa where their efficiency is about 50,000 plates per meter and in the CEC mode where efficiency is about 106,000 plates per meter at 5 kV. There is a relatively rapid loss of efficiency with increasing linear velocity beyond 0.2 mm/s in microLC mode, which may be due to additional diffusion processes in the inter‐particulate voids. A rapid loss of efficiency above 0.5 mm/s is also observed in the CEC mode, for the same reasons. Chromatographic retention behavior in either separation mode is characteristic of conventional octadecylsilica particles, indicating that analytes have significant access to the surface within the pores of the immobilized bonded phase. 相似文献
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高效毛细管区带电泳法分离人血清蛋白质的研究 总被引:4,自引:0,他引:4
研究了高效毛细管区带电泳分离人血清蛋白质的电泳行为及实验条件 ,建立了分离血清蛋白质的高效毛细管区带电泳法。血清样品经硼酸缓冲液 (5 0 mmol/L,p H8.80 )稀释后 ,以 0 .1 mol/L硼酸缓冲液 (p H9.3 5 ,含4g/L PEG80 0 0 )为电泳介质 ,在 5 0 μm i.d.× 3 7cm弹性石英毛细管柱 (有效柱长为 3 2 cm)中进行电泳分离 ,以2 0 0 nm紫外波长检测。方法简便、快速、重复性好 ,1 2 min内便可完成对血清中蛋白质的电泳分离。 相似文献
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采用手性衍生化法,实验室合成了L-丝氨酸甲酯盐酸盐作为手性和衍生试剂,用于萘普生和-β-2-丙酸对映异构体的柱前衍生,以酰氯化间接衍生或缩水剂N,N‘-二环己基碳化二亚胺直接衍生形成酰胺非对映异构体对,然后用常规硅胶柱分离,同时利用色谱保留值规律和光谱特征吸收曲线综合进行定性分析。 相似文献
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填充毛细管液相色谱—毛细管气相色谱在线联用分析柴油全组成 总被引:5,自引:0,他引:5
采用填充毛细管液相色谱(PC-HPLC)与毛管气相色谱(CGC)在线联用技术分析柴油全组分。半填充硅胶、半填充氨基的PC-HPLC柱(0.32mm i.d)用于样品族分离(烷烃、单环芳烃、双环芳烃、三环芳烃和胶质)。经PC-HPLC分离后的各族组分(峰体积小于30μL)被依次存放在多位储存接口内,然后分别转入GC作单个组分定量分析,可得出各族组分的相对含量及烷烃的碳数的正异构分布。该方法是分析柴油 相似文献
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毛细管电泳法测定性保健品中的西地那非 总被引:15,自引:0,他引:15
用毛细管电泳法测定了万艾可片剂和两种市售性保健品中的西地那非。以 6 0mmol/L磷酸二氢钠溶液为缓冲溶液 (pH 5 0 ) ,在 35℃ ,30kV的条件下进行测定 ,结果西地那非的质量浓度为 0 0 7g/L~ 1 0 5 g/L时与相应峰面积的线性关系良好 (r =0 9985 ) ;在实际样品中的平均回收率为 97 4 % ;方法的重现性好 ,峰面积的RSD为4 7%。与目前通行的高效液相法测定西地那非的结果相比 ,毛细管电泳方法所测得的结果同样准确可靠 ,而且样品处理简便 ,测试时间短 ,测试成本低 ,因此可以作为测定西地那非的一种简便而准确的方法。 相似文献
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Salvatore Fanali Claudia Desiderio Eva
lveck Duan Kaniansky Marek Vojtek Adriana Ferancov 《Journal of separation science》2000,23(9):531-538
The ability of capillary zone electrophoresis (CZE) coupled on‐line with capillary isotachophoresis (ITP) sample pretreatment in the column‐coupling capillary electrophoresis equipment to separate trace enantiomers present in samples of complex ionic matrices and enantiomers present in their mixtures at significantly differing concentrations has been studied. Enantiomers of 2,4‐dinitrophenyl labeled norleucine (DNP‐Nleu) and tryptophan enantiomers were employed as model analytes in this work while urine and mixtures of tryptophan enantiomers of differing concentrations served as model samples. Experiments performed with urine samples spiked with the DNP‐Nleu racemate at sub‐μmol/L concentrations demonstrated excellent sample pretreatment capabilities of ITP (concentration of the analytes, in‐column and post‐column sample clean up) when coupled on‐line with chiral CZE separations. In the CZE separations of enantiomers present in the samples at trace concentrations the sample pretreatment could be performed in both achiral and chiral ITP electrolyte systems. The use of a chiral electrolyte system was found to be essential in the ITP pretreatment of the samples containing the enantiomers at very differing concentrations. For example, a 2×10–7 mol/L concentration of L‐tryptophan could be detected in the CZE separation stage of the ITP‐CZE combination in samples containing about a 104 excess of D‐tryptophan only when the ITP pretreatment was carried out in the electrolyte system providing the resolution of enantiomers (α‐cyclodextrin served for this purpose in the present work). A post‐column ITP sample clean up was found effective in enhancing the destacking rate of the trace enantiomer in the CZE stage when the migration configuration of the enantiomers was less favorable (the trace constituent migrating behind the major enantiomer). 相似文献