High-sensitivity detection using isotachophoresis with variable cross-section geometry
High-sensitivity detection using isotachophoresis with variable cross-section geometry
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DOI：
10.1002/elps.201000338
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发表时间：
2011-02-01
期刊：
影响因子：
2.9
通讯作者：
Santiago, Juan G.
中科院分区：
文献类型：
--
作者：
Bahga, Supreet S.;Kaigala, Govind V.;Santiago, Juan G.
我们提出了一个理论和实验研究，通过改变通道截面增加ITP检测的灵敏度。本文提出了一个简单的、非定常的、无扩散的平台模式ITP模型。我们的模型考虑到详细的化学平衡计算，并处理任意变化的通道横截面。我们已经验证了我们的模型与ITP的一个更全面的模型的数值模拟。我们发现，使用强收敛通道可以导致一个大的增加灵敏度和同时减少测定时间，相比均匀的横截面通道。我们已经验证了我们的理论预测与详细的实验，通过改变通道的几何形状和分析物浓度。我们展示了使用强会聚通道的有效性，通过展示间接荧光检测，灵敏度为100 nM。我们还提出了简单的分析关系的依赖区域长度和测定时间的几何参数的强收敛通道。我们的理论分析和实验验证提供了有用的指导原则，优化芯片的几何形状，在所需的检测时间，芯片面积和电源的约束下，最大限度地提高灵敏度。
We present a theoretical and experimental study on increasing the sensitivity of ITP assays by varying channel cross-section. We present a simple, unsteady, diffusion-free model for plateau mode ITP in channels with axially varying cross-section. Our model takes into account detailed chemical equilibrium calculations and handles arbitrary variations in channel cross-section. We have validated our model with numerical simulations of a more comprehensive model of ITP. We show that using strongly convergent channels can lead to a large increase in sensitivity and simultaneous reduction in assay time, compared to uniform cross-section channels. We have validated our theoretical predictions with detailed experiments by varying channel geometry and analyte concentrations. We show the effectiveness of using strongly convergent channels by demonstrating indirect fluorescence detection with a sensitivity of 100 nM. We also present simple analytical relations for dependence of zone length and assay time on geometric parameters of strongly convergent channels. Our theoretical analysis and experimental validations provide useful guidelines on optimizing chip geometry for maximum sensitivity under constraints of required assay time, chip area and power supply.