A Novel Electrical Microfluidics System Actuated by Biological Cell Motors

0201004Tung微米和纳米技术的下一个趋势是将微米和纳米系统与活性生物元素和信息转导手段相结合。沿着这条路线，PI的建议，设计，制造和测试一种新的电动微流体泵驱动的生物细胞马达。建议的微泵将通过整合一个无害的E.大肠杆菌细胞与基于MEMS的微流体通道。每个E.大肠杆菌细胞由几个鞭毛组成，鞭毛在基部由旋转马达驱动。如果细胞通过一根鞭毛丝附着在一个表面上，马达就会使整个细胞体高速旋转。所提出的设计利用该机制通过粘性泵送在微流体通道中输送液体。根据初步的流体力学模拟，所提出的细胞马达泵可以提供几乎每分钟0.25纳升的流速。电旋转将用于电控制单元旋转速度，从而控制流速。通过这种新颖的控制方案，可以预见，细胞驱动生物学和MEMS的集成将导致下一代应用的智能微流体系统。该项目的目标如下：设计和制造MEMS微流体通道：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率对微流体通道中的微流体的体积流率的依赖性。细胞马达的分布和旋转速度。基于这些结果，将使用MEMS处理技术在硅衬底上制造微流体通道系统。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。将细胞与微流体通道集成：金将用作细胞与微流体通道之间的界面材料。将采用两种成熟的技术将细胞附着到金图案化基底上。一个涉及产生用于鞭毛丝附着的合适基质。第二集中在工程鞭毛丝，将提供良好的配体连接。

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.