Dispersion sources for compact geometries on microchips
Dispersion sources for compact geometries on microchips
复制标题
DOI：
10.1021/ac9804487
复制
发表时间：
1998-09-15
影响因子：
7.4
通讯作者：
Ramsey, JM
中科院分区：
文献类型：
--
作者：
Culbertson, CT;Jacobson, SC;Ramsey, JM
折叠微芯片装置中的分离通道通常通过迁移距离和场强的横向变化对分析物分散引入额外的几何贡献。所产生的几何色散取决于分析物横向扩散时间与分析物条带穿过转弯所花费的时间的比率。已经开发了一个一维模型，该模型预测了在微芯片通道中轮流引入的过量分散体的量。该模型考虑了迁移长度差异、场强差异和横向扩散效应，准确地描述了实验数据。在微芯片上的通道中引入转弯被示出为与在直通道中的相同分离长度相比降低分离效率，特别是对于具有小扩散系数的分子。几种方法，以减少几何分散检查，包括操纵通道宽度和分析物的速度和使用的互补对转弯。
Folding the separation channel in a microchip device generally introduces an additional geometrical contribution to analyte dispersion through lateral variations in both migration distance and field strength. The geometrical dispersion generated depends on the ratio of the analyte transverse diffusion time to the time that the analyte band spends traversing the turn. A one-dimensional model has been developed which predicts the amount of excess dispersion introduced by turns in microchip channels. This model accounts for migration length differences, field strength differences, and transverse diffusion effects and accurately describes the experimental data. The introduction of turns into the channel on a microchip is shown to reduce separation efficiency compared to the same separation length in a straight channel, especially for molecules with small diffusion coefficients. Several methods to reduce geometrical dispersion are examined including the manipulation of channel width and analyte velocity and the use of complementary pairs of turns.