OPTIMIZATION IN SAMPLE STACKING FOR HIGH-PERFORMANCE CAPILLARY ELECTROPHORESIS
OPTIMIZATION IN SAMPLE STACKING FOR HIGH-PERFORMANCE CAPILLARY ELECTROPHORESIS
复制标题
DOI：
10.1021/ac00018a028
复制
发表时间：
1991-09-15
影响因子：
7.4
通讯作者：
CHIEN, RL
中科院分区：
文献类型：
--
作者：
BURGI, DS;CHIEN, RL
本文提出了一个简单的重力进样样品堆积峰方差的优化模型。 在样品堆积中，将含有待分离样品的低浓度缓冲液的长塞引入填充有相同组成但浓度更高的缓冲液的柱中。 然后，样品离子在样品塞中的增强的外加电场下非常迅速地迁移，直到它们到达浓度边界。 一旦它们穿过边界，离子就会减速并堆积成窄带。 理论上，样品堆积中的峰宽与原始样品溶液中缓冲液浓度与色谱柱中缓冲液浓度的比值γ成正比。 然而，毛细管柱内的浓度的这种差异也产生源自浓度边界的电渗透压。 由电渗透压引起的层流导致额外的峰增宽。 样品堆叠和层流增宽相互作用，以产生与样品缓冲液浓度、分离缓冲液浓度和样品塞长度相关的最佳点。 模型的预测结果与实验结果吻合较好。
A simple model for the optimization of peak variance in sample stacking with a gravity-injected sample has been developed. In sample stacking, a long plug of low-concentration buffer containing a sample for separation is introduced into a column filled with a buffer of the same composition but of a higher concentration. The sample ions then migrate very rapidly under the enhanced applied electric field in the sample plug until they reach the concentration boundary. Once they cross the boundary, the ions slow down and stack into a narrow band. Theoretically, the peak width in sample stacking is proportional to the ratio, gamma, of buffer concentration in the original sample solution to that in the column. However, this difference in the concentrations inside the capillary column also generates an electroosmotic pressure originating at the concentration boundary. The laminar flow resulting from the electroosmotic pressure causes extra peak broadening. Sample stacking and laminar broadening work against each other to yield an optimal point relating to the sample buffer concentration, the separation buffer concentration, and the sample plug length. The predications of the model are in agreement with experimental results.