Sintered octadecylsilica as monolithic column packing in capillary electrochromatography and micro high-performance liquid chromatography
Sintered octadecylsilica as monolithic column packing in capillary electrochromatography and micro high-performance liquid chromatography
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DOI：
10.1016/s0021-9673(98)00052-1
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发表时间：
1998-05-15
影响因子：
4.1
通讯作者：
Horváth, C
中科院分区：
文献类型：
--
作者：
Asiaie, R;Huang, X;Horváth, C
用多孔6 μ m十八烷基化二氧化硅微球填充熔融二氧化硅毛细管，并进行热处理，以获得具有多孔二氧化硅基整体填料的柱。烧结后，整体填料再十八烷基原位与二甲基十八烷基氯硅烷。整体柱的机械强度和稳定性显着大于常规填充颗粒固定相的柱。在μ-HPLC和毛细管电色谱法（CEC）的小的芳香族化合物和多环芳烃与10 mM berate，pH 8.0，在乙腈-水的混合物作为移动的相的性能进行了评价。由于没有观察到不利的气泡形成，CEC可以在CZE单元中进行，而不需要对整体柱加压。的整体柱的板效率是类似的新鲜填充有相同的颗粒的列，并始终高于在其他相同的条件下，在CEC比在μ-HPLC。在开放的熔融石英毛细管与十八烷基化的内壁和填充有烧结十八烷基硅胶柱的洗脱液中的乙腈含量的电渗流动（ESTA）的速度增加。相反，在粗熔融石英毛细管中，洗脱速度随着洗脱液的有机强度而降低。相反的趋势归因于改变有机改性剂浓度对硅醇基团在原料和十八烷基化二氧化硅表面的可及性的不同影响。(C)1998年Elsevier Science B.V.
Fused-silica capillaries were packed with porous 6-mu m octadecylated silica microspheres and subjected to thermal treatment in order to obtain a column with porous silica based monolithic packing. After sintering, the monolithic packing was reoctadecylated in situ with dimethyloctadecylchlorosilane. The mechanical strength and stability of the monolithic column were significantly greater than those of conventional columns packed with particulate stationary phase. The performance of the columns was evaluated in both mu-HPLC and capillary electrochromatography (CEC) of small aromatic compounds and polycyclic aromatic hydrocarbons with 10 mM berate, pH 8.0, in acetonitrile-water mixtures as the mobile phase. Since no untoward bubble formation was observed, CEC could be performed in a CZE unit without the need for pressurizing the monolithic column. The plate efficiency of the monolithic column was similar to that of columns freshly packed with the same particles and was always higher in the CEC than in the mu-HPLC under otherwise identical conditions. The electrosmotic flow (EOF) velocity increased with the acetonitrile content of the eluent in open fused-silica capillaries with octadecylated innerwall and in columns packed with sintered octadecylsilica. In contradistinction, the EOF velocity decreased with the organic strength of the eluent in raw fused-silica capillaries. The opposite trend is attributed to the different effect of changing organic modifier concentration on the accessibility of silanol groups at the raw and octadecylated silica surfaces. (C) 1998 Elsevier Science B.V.