CAREER: Developing Asymmetric-Polarization AC Electroosmosis for Lab-on-a-chip

研究的目标是开发和验证一个电动芯片上的实验室，用于稳健和快速检测低浓度生物颗粒(例如。水、食物和临床样本中的病毒、细菌、细胞)。这项研究解决了此类检测长期存在的灵敏度和选择性的瓶颈问题。该方法是：1)根据不同的电荷/质量比，根据生物粒子对电动输运的响应来区分生物粒子；2)通过加速生物粒子通过对流扩散到传感器来快速浓缩局部粒子浓度；3)在引入电动信号放大的同时，通过阻抗测量来量化粒子浓度。上述功能是通过非对称极化交流电渗透来实现的，它是新发现的，处于电动微流体研究的前沿。这种单芯片实验室工作在低电压、低功耗的情况下，其所有的电子处理有利于现场生物物品检测的便携性、并行性和自动化。生物物品检测具有重要意义，因为生物物品经常作为病原体和/或毒素的载体/指示物。随着世界日益关注传染病和生物恐怖主义对食品、水和环境造成的毒素/病原性污染，而且由于及早发现病原体/毒素对社会的威胁可以大大减轻，民用和军事应用对快速生物物品检测的需求正在扩大。该研究所提出了一种新型的电动芯片实验室，用于检测低浓度的生物粒子。这项研究不仅将产生实用的检测芯片，还将为学生提供一个独特的机会，探索微系统、生物/化学/电子学和微流变学的跨学科研究现状。

The research objective is to develop and validate an electrokinetic lab-on-chip forrobust and rapid detection of low concentration bioparticle (eg. virus, bacteria, cells) inwater, food and clinical samples. The research tackles the long-standing bottleneckissues of sensitivity and selectivity for such detection. The approach is: 1) to differentiatebioparticles by their response to electrokinetic transport based on various charge/massratio, 2) to rapidly enrich local particle concentration by expediting bioparticles' diffusionto sensors with convection, and 3) to quantify particle concentration by impedimetricmeasurement while incorporating electrokinetic signal amplification. The abovefunctions are to be realized by asymmetric-polarization AC electro-osmosis, which isnewly discovered and at the forefront of electrokinetic microfluidic research. Such lab-on-a-chip operates at small voltage with low power consumption, and its all electricalprocesses facilitate portability, parallelism and automation for on-site bioparticledetection.Bioparticle detection is of great significance because bioparticles often serve ascarrier/indicator of pathogens and/or toxins. As the world becomes increasinglyconcerned with toxin/pathogenic contamination in food, water and environment frominfectious diseases and bioterrorism, and because the threat of pathogen/toxins tosocieties could be substantially mitigated with early detection, the demand for rapidbioparticle detection is expanding for both civilian and military applications. The PIproposes a novel electrokinetic lab-on-a-chip to detect bioparticles at low concentrations.The research will not only lead to a practical detection chip but also afford students aunique opportunity to explore the state-of-art of interdisciplinary research inmicrosystem, bio/chemi/electronics and microfluidics.