A Novel Electrical Microfluidics System Actuated by Biological Cell Motors

微纳米技术的下一个趋势是将微纳米系统与活跃的生物元素和信息传递手段相结合。沿着这一思路，PI提出了设计、制造和测试一种由生物细胞马达驱动的新型电动微流体泵。建议的微泵将通过将无害的大肠杆菌菌株与基于MEMS的微流体通道相集成来实现。每个大肠杆菌细胞由底部由旋转马达驱动的几个鞭毛组成。如果细胞通过单个鞭毛细丝附着在表面，马达就会以较高的转速转动整个细胞体。所提出的设计利用该机构通过粘性泵在微流体通道中输送液体。根据初步的流体力学模拟，所提出的电池马达泵可以提供几乎每分钟0.25纳升的流量。电旋转将被用来电控制电池的转速，从而控制流量。在这种新的控制方案下，细胞驱动生物学和MEMS的拟议集成将产生面向下一代应用的智能微流控系统。为所提议的项目设定了以下目标。设计和制造MEMS微流控通道：将进行一系列流体动力学模拟，以研究微流体通道中的体积流量与单元马达的分布和转速的关系。在此基础上，利用MEMS加工技术在硅衬底上制作了微流控通道系统。通道的侧壁将由用于细胞附着的金垫和用于通过电旋转控制细胞旋转的金属电极组成。电池与微流体通道一体化：金将作为电池与微流体通道之间的界面材料。将采用两种成熟的技术将电池连接到金色图案的衬底上。一种是产生适合附着鞭毛细丝的底物。第二个重点是设计鞭毛细丝，为附着提供良好的配体。

0201004TungThe next trend in micro and nano technology is in the direction of integrating micro and nano systems with active bio-elements and means of information transduction. Along this line, the PI's propose to design, fabricate, and test a novel electrical microfluidics pump actuated by biological cell motors. The proposed micro pump will be realized through the integration of a harmless strain of E. coli cells with a MEMS-based microfluidics channel. Each E. coli cell consists of several flagella driven at the base by a rotary motor. If the cell is attached to a surface by a single flagellar filament, the motor turns the whole cell body at a high rotational speed. The proposed design utilizes this mechanism to transport liquid in a microfluidics channel through viscous pumping. According to a preliminary fluid mechanics simulation, the proposed cell motor pump can deliver a flow rate of almost 0.25 nanoliter per minute. Electro-rotation will be used to electrically control the cell rotational speed and thus the flow rate. With this novel control scheme, it is envisioned that the proposed integration of cell actuation biology and MEMS will result in an intelligent microfluidics system for next generation applications.The following objectives have been established for the proposed project.Design and fabricate MEMS microfluidics channel: A series of fluid dynamics simulations will be conducted to investigate the dependence of the volumetric flow rate in a microfluidics channel on the distribution and rotational speed of cell motors. Based on the results, a microfluidics channel system will be fabricated using MEMS processing techniques on a silicon substrate. The sidewall of the channel will consist of gold pads for cell attachment and metal electrode for controlling cell rotation through electro-rotation.Integrate cells with microfluidics channel: Gold will be used as the interface material between the cells and the microfluidics channel. Two mature technologies will be adapted to attach the cells to a gold patterned substrate. One involves generation of a suitable substrate for attachment of the flagellar filaments. The second concentrates on engineering flagellar filaments that will provide good ligands for attachment.