Biomedical Engineering Department, The University of Memphis, Memphis, Tennessee 38152, USA.
Anal Chem. 2009 Dec 15;81(24):9955-60. doi: 10.1021/ac9016659.
Surface energy in small droplets can be used to drive samples through microchannels. When a sample fluid is spontaneously driven through a solution filled microchannel with liquid droplets on its entry (sample) and exit (reservoir) ports, it is termed as a passive pumping device. A passive pump driven microfluidic system integrated with microfabricated planar electrodes or electrode arrays (e.g., interdigitated electrode arrays or microband electrode arrays) can be considered as a manifold for flow injection analysis without an external pump and injector valve. Factors affecting the passive pump driven flow rate in a polydimethylsiloxane (PDMS)-glass hybrid microfluidic system, including the volume, viscosity, and surface tension of the sample solution and the tilt of the microfluidic channel, are analyzed. By placing 2 microL of hexacyanoferrate (II) solutions at the entry port of the device, peak shaped transients were recorded. The peak heights showed linear dependence on the sample concentrations between 3 x 10(-7) and 10(-5) M.
表面能可用于驱动微通道中的样本。当样本溶液在入口（样品）和出口（储液器）端口处被自发地驱动通过充满液体微滴的微通道时，它被称为被动泵送装置。与微制造平面电极或电极阵列（例如，叉指电极阵列或微带电极阵列）集成的被动泵驱动微流控系统可以被认为是没有外部泵和注射器阀的流动注射分析的歧管。分析了影响聚二甲基硅氧烷（PDMS）-玻璃混合微流控系统中被动泵驱动流速的因素，包括样品溶液的体积、粘度和表面张力以及微流道的倾斜度。通过在器件的入口端口处放置 2 μL 的亚铁氰化钾（II）溶液，记录到峰形瞬变。峰高显示出在 3 x 10(-7) 到 10(-5) M 之间的线性依赖于样品浓度。
