Development of dielectrophoresis chromatography employing asymmetric insulating structures and electric fields

芯片实验室能够在一个电子设备中自动执行多种复杂的化学诊断，这个电子设备很容易戴在你的拇指上。由于芯片实验室操纵的是极小体积的流体，因此它也被称为微流体装置。小型化实现了便携性和可访问性，并为将化学实验室带到需要的地方打开了大门，无论是生产线，远程医疗诊所，敏感环境还是食品和水安全的真实的实时监控。 从技术角度来看，小型化导致更高的分辨率和灵敏度，改进的集成度，更低的成本和极快的处理时间。为了操纵和分选生物颗粒，如细胞和复杂的大分子，介电泳是最常用的技术之一，因为它依赖于颗粒对所施加电场的响应差异。活细胞和死细胞对非均匀电场的反应与死细胞不同，不同生物体的细胞也是如此。 基于绝缘体的介电电泳为颗粒分选增加了另一个“旋钮”，三维绝缘结构的放置作为颗粒迁移路径中的障碍物，其“挤压”电场。 理论预测，使用不对称的障碍物提供了另一个“旋钮”来分类粒子。该项目将通过实验验证使用非对称绝缘结构和非均匀电场在微流体装置中分选和分离生物颗粒。不对称绝缘介电电泳将在一些生物粒子中引起加速，而在另一些生物粒子中引起减速，其中瞬时速度由粒子几何形状和电荷决定。加速度的差异将导致不同的停留时间，产生类似于色谱过程的分离，从而创建介电泳色谱的第一个演示。将精心设计的绝缘柱几何形状与基于绝缘体的介电泳中的定制DC偏置低频AC电信号相结合，用于筛选各种感兴趣的生物颗粒，其大小，形状和电荷各不相同。色谱效应将导致与固定相的明显相互作用，以及颗粒通过装置的差异迁移。 颗粒将从固定相洗脱作为一个？高峰期？并被引导至装置内的特定储存器以进行收集。该项目将通过开发一种新的分选和分离颗粒的技术来推进微流体技术的发展。本项目将为本科生和研究生提供一个首要的研究机会，并将通过妇女参与工程方案协助为女学生提供研究机会。

A lab-on-a-chip is capable of automatically performing multiple complex chemical diagnostics in an electronic device that will easily fit on your thumb. As a lab-on-a chip manipulates an extremely small volume of fluid, it is also termed a microfluidic device. Miniaturization enables portability and accessibility, and opens the door for taking the chemical laboratory to where it is needed, be that a production line, a remote medical clinic, a sensitive environment, or real time monitoring of food and water safety. From a technical standpoint, miniaturization leads to higher resolution and sensitivity, improved integration, lower cost, and an extremely rapid processing time. To manipulate and sort biological particles, such as cells and complex macromolecules, dielectrophoresis is one of the most common techniques, as it relies on differences in particle response to an applied electric field. Living and dead cells respond differently to a nonuniform electric field than dead cells, as do cells from different organisms. Insulator-based dielectrophoresis adds another "knob" for particle sorting, with the placement of three-dimensional insulating structures as obstacles in the path of particle migration which "squeeze" the electric field. Theory predicts that using asymmetric obstacles provides yet another "knob" to sort particles. This project will experimentally validate the use of asymmetric insulating structures and nonuniform electric fields to sort and isolate biological particles in a microfluidic device. Asymmetric insulating dielectrophoresis will induce acceleration in some biological particles, and deceleration in others, with instantaneous velocity determined by particle geometry and charge. Differences in acceleration will lead to different residence times, creating a separation that is similar to a chromatographic process, creating the first demonstration of dielectrophoretic chromatography. A combination of carefully designed insulating post geometries with customized DC-biased, low frequency AC electric signals in insulator-based dielectrophoresis will be used to screen various bioparticles of interest, with variations in size, shape, and charge. The chromatographic effect will lead to distinct interaction with the stationary phase, and differential migration of the particles through the device. Particles will be eluted from the stationary phase as a ?peak? of concentrated particles and directed to a specific reservoir within the device for collection. This project will advance the state of the art in microfluidics by developing a new technique to sort and isolate particles. The present project will provide a premier research opportunity for undergraduate and graduate students, and will also assist in providing research opportunities for female students through the Women in Engineering programs.