台锥形液相色谱柱内谱带流型的动态可视化研究  

Study of the Dynamic Flow Profile in Conical Shaped Liquid Chromatographic Columns by Visualization Method

作　　者：马继平[1] 陈令新[1] 朱道乾[1] 关亚风[1] 

机构地区：[1]中国科学院大连化学物理研究所

出　　处：《色谱》2003年第2期106-109,共4页Chinese Journal of Chromatography

基　　金：国家自然科学基金资助项目(批准号:20075030).

摘　　要：利用自制的台锥形色谱柱内谱带流型可视化研究装置,对台锥形色谱柱内样品谱带的流型进行研究。将以有机玻璃为柱管、内填C18色谱固定相的色谱柱浸入无毒溶剂丙三醇池中,以消除圆柱或圆锥的透镜效应。当以环己烷为流动相时,即使在中心点进样的情况下也可清晰地观察到色谱柱内有色样品碘的谱带流型。流型图像的数字信号利用数码照相机获取。通过对入口内径大于出口内径的台锥形与出入口内径相同的圆柱形柱内样品谱带的流型研究发现,在相同的实验条件下,台锥形柱内呈现与圆柱形柱内样品谱带流型曲率方向相反的抛物线流型。这是由台锥形柱特殊的结构造成的。由于台锥形柱斜面的存在使流体在管壁区的受力情况不同于圆柱的管壁区,因此通过改变台锥形柱的结构有可能获得具有塞子状的流型,这对于提高色谱柱柱效具有重要指导意义。The dynamic flow profile inside a conically shaped column for preparative liquid chromatography was studied by using a selfmade device where the movement of a colored sample in the column could be observed clearly and truly. The transparent chromatographic columns made of polymethyl methacrylate (PMMA), packed with C18 bonded silica, were immersed in a pool filled with innoxious solvent of glycerol to eliminate the cylindrical and conical lens effect. With the iodinecontaining cyclohexane as the colored mobile phase, the flow profiles were visualized clearly, including the central point injection mode. Since the refractive indices of the stationary phase C18, the column wall and the mobile phase are very close. Images of flow profiles were recorded with a digital camera. It was found that under the same experimental conditions the flow profile of solute band in the conical column with a larger inlet inner diameter than outlet inner diameter was observably different from that in cylindrical column. In the conical column, the band migrated in the central region of the column slower than that in the wall region, resulting in a reverse parabolic flow profile in contrast to that in cylindrical column. Such observation resulted from the special shape of the conical column, in which the composition of forces near the conical column wall was different from that near the cylindrical column wall owing to the existence of the inclined plane. The results demonstrate that it is possible to develop preparative LC columns with pluglike flow profile and improved column efficiency by controlling an appropriate angle of the conical column.

关 键 词：台锥形液相色谱柱 谱带流型 动态可视化 液相色谱 柱效 

分 类 号：O657.72[理学—分析化学]