双T型通道微流控芯片中场放大样品富集的数值分析

The Numerical Analysis on field-amplified Sample Stacking in Double-T Channel Microfluidic Chip

通过合理的简化和假设,建立了一个包括电势分布方程、缓冲溶液浓度方程和样品粒子电迁移扩散方程的一维数学模型,并应用有限元方法对该模型进行了求解.计算得到了富集过程中样品浓度峰值出现的时间和位置,给出不同时刻表面带正、负电荷样品粒子的分离效果,对缓冲溶液浓度比值不同时的富集效果进行了分析.该模型可为芯片上场放大样品富集过程提供一定的理论预测和指导.

A 1-D mathematical model including electrical potential distribution equation, buffer concentration equation, as well as sample electromigration and diffusion equation was developed through proper simplification and assumption to study sample stacking process in microfluidic chips. These governing equations were solved simultaneously using finite element method. The position and time that the maximal sample concentration appears, as well as the separation effect of cations and anions at different time in sample stacking were obtained through the simulation results. The effect of buffer concentration ratio on sample stacking effect was also analyzed. It is anticipated thar the numerical model developed in this paper is helpful to predict the sample stacking process.