Abstract
In the development of the lab chip, cell manipulation is always an important issue. How to guide or position cell accurately would determine whether the experiment result is good or not. Besides, the technique chosen is almost critical. The inappropriate technique would damage the cells easily, and result in either degradation of cell function, or even cell death. In the techniques developed nowadays, involved with microfluidic channel and microfluidic components, researchers often adopt electrodynamics method, either dielectrophoresis or electroosmosis, optical tweezers, magnetic manipulation, microgrippers to achieve the goal of cell manipulation. However, these techniques have inherent drawbacks. For example, the buffer needed in dieletrophoresis and electroosmosis is usually not suitable for cell viability. Also the power of optical tweezers might result in some damage on cell. Based on the idea of microcage and the design of Lobster-sniffing inspired biomimic actuator developed by our lab, we introduce the idea of putting a small structure on a PDMS thin membrane with some offset to approach similar functions. While the PDMS thin membrane is actuated by the syringe pump, the small structure could provide a lateral actuation. Compared with the microfluidic electrodynamics, such an actuation method would have no constraint on the working fluid. The experiments show that it could function well in the cell culture solution, and even blood fluid. Also, benefited from the syringe pumps, such an actuation would provide large actuation rage and large force in the microchannel. At this stage, an easy calculation for membrane deformation model, ANSYS simulation for membrane deformation, device design, chip development, and the measurement for the characteristics of the chip have been finished. Also, an experiment for the trap and release of spheroids in culture medium has been demonstrated preliminarily, showing the practice of our PDMS membrane actuator.