采用中孔SBA-15棒状硅胶颗粒填充毛细管柱用于毛细管电色谱(CEC)分离。这一亚微米材料直径为400nm并具有沿相同方向伸展的高度有序、均一的圆柱形中孔。棒状的特殊形态使得填充柱的通透性良好,简化了尺寸微小的CEC柱的填充过程。修饰后的棒状SBA-15填充毛细管柱成功应用于反相和离子交换电色谱分离非极性和极性样品,获得了较高柱效(140 000理论塔板/m)。流速3.2 cm/min时获得最低理论塔板高度为7.1 mm。范迪米特曲线说明了SBA-15孔结构的传质阻力特征。分别以芳香酸、人参、天麻提取物为样品,对亚微米固定相毛细管电色谱柱加以评价。该固定相显示出了较高的分离能力,为纳米材料在色谱固定相中的应用提供了一个新的思路。
Mesoporous SBA-15 silica rods were packed into capillary as stationary phase for capillary electrochromatography(CEC) separation.The attractive properties of the sub-micrometer material are its radical size of 400 nm and highly ordered cylindrical mesopores running along the same direction.The special structure is formed by piling of rod shape particles,which provide good permeability and facilitate the packing procedure of small size CEC column.The modified silica particles were successfully applied for the reversed-phase(RP) and ion-exchange(IE) electrochromatographic separation of non-polar and polar compounds with satisfactory efficiency(140 000 plates/m for benzene using 70%(v/v) acetonitrile).The van Deemter plot showed the hindrance to mass transfer because of the existence of pore structure.The lowest plate height of 7.1 mm was obtained at the linear velocity of 3.2 cm/min.The prepared ion exchange column was applied to the separation of Chinese traditional medicines Ginseng and Rhizoma Gastrodiae.