An open source for multiplexed, stable and transient flows to advance life science using microfluidic control automation

Abstract

Multiplexed fluid control is a demanding task in various life sciences and bioengineering research. We here present an open-source microfluidic sequence automation (MiSA) that offers flexible and multiplexed fluid control for various applications, providing a constant flow via pressure-based feedback control with 10-plex capability and pulsed flow in the order of 100 ms. MiSA is self-contained, including a pressure source, and employs an Arduino Micro to integrate ten solenoid valves, an off-the-shelf pressure regulator, and a flow sensor to balance cost and reliability. To offer stable microflow control, especially at a low flow rate under a low flow resistance, MiSA uses a potentiometer that tunes the range of the pressure control by effectively leveraging the full 8-bit output from the Arduino Micro applied to the pressure regulator. We demonstrate the practical use of MiSA for multiplexed chemical reactions by performing the hybridization-based in situ sequencing. To demonstrate the flexibility of MiSA, we show the extensions of our system for two pressure regulations under open-loop control in the flow rate by demonstrating three independent applications for droplet generation, microfluidic spinning of spider silk fiber, and atomization of protein solution. We envision that this open source will offer resources for researchers to quickly explore microfluidic applications with an affordable investment.