On-chip actuation transmitter for enhancing the dynamic response of cell manipulation using a macro-scale pump

An on-chip actuation transmitter for achieving fast and accurate cell manipulation is proposed. Instead of manipulating cell position by a directly connected macro-scale pump, polydimethylsiloxane deformation is used as a medium to transmit the actuation generated from the pump to control the cell position. This actuation transmitter has three main advantages. First, the dynamic response of cell manipulation is faster than the conventional method with direct flow control based on both the theoretical modeling and experimental results. The cell can be manipulated in a simple harmonic motion up to 130 Hz by the proposed actuation transmitter as opposed to 90 Hz by direct flow control. Second, there is no need to fill the syringe pump with the sample solution because the actuation transmitter physically separates the fluids between the pump and the cell flow, and consequently, only a very small quantity of the sample is required (<1 μl). In addition, such fluid separation makes it easy to keep the experiment platform sterilized because there is no direct fluid exchange between the sample and fluid inside the pump. Third, the fabrication process is simple because of the single-layer design, making it convenient to implement the actuation transmitter in different microfluidic applications. The proposed actuation transmitter is implemented in a lab-on-a-chip system for red blood cell (RBC) evaluation, where the extensibility of red blood cells is evaluated by manipulating the cells through a constriction channel at a constant velocity. The application shows a successful example of implementing the proposed transmitter.