Microfluidic Flow Rate Control Device: From Concept to Product Through Additive Manufacturing

Recent growth of the microfluidics technology field and its applications demands more modular, flexible, reliable, easy to use and complete solutions. One key component in a microfluidic system is the section in charge of propelling and controlling flow through the microfluidic chip, this consists mainly of an impulsion (actuator) part, a sensor to read a signal and feed it to the actuator which modifies flow, and a closed control loop to set the desired operating point. Present solutions are not completely integrated as a final product to the user, but merely as a group of components which need to be coupled. The approach presented here provides one single plug and play device for liquids. Users only have to connect it to the hydraulic circuit of their microfluidic system and define a flow rate set point to start their experiments, thus avoiding setup difficulties. This microfluidic flow rate control device consists mainly of an electronics control board and a fluidic section composed of sensors and actuators. For the latter component, DLP 3D printing process of additive manufacturing was used as a rapid prototyping tool, going from conceptual design to a final product in a few months. Feedback between real performance and numerical modelling allowed operation improvements in the equipment thanks to fast prototyping and testing capacity. Finally, a fully integrated plug and play system which controls flows in a range of 10–1000 µL/min with a ± 1 µL/min resolution and easily coupled to microfluidic lines is obtained. In summary, additive manufacturing contributes not only as a tool to build new ideas, but also to optimize an already designed device, thanks to reduced costs and simplified fabrication processes for complex three-dimensional structures.