Sound valve-control for programmable microfluidic devices

In the domain of microfluidic devices, a paradigm shift from application-specific to fully-programmable solutions takes place (a similar development from ASICS to FPGAs has been observed in conventional circuitry). So-called Programmable Microfluidic Devices (PMDs) provide a promising platform in this regard. Here, fluids can be pushed into various reaction vessels whose inflow and outflow is controlled by valves. The regular structure in combination with the flexibility of defining various flow paths through valves allows to realize a vast range of biological or chemical applications by only changing the corresponding valve-control sequence. However, determining a sound valve-control constitutes a non-trivial task. Although first automatic approaches for this problem have recently been proposed, we show that they frequently yield impractical control sequences. In this work, we address this issue by providing a precise definition of the underlying design task. Afterwards, we present complementary solutions (both exact as well as heuristic) and discuss how they guarantee a sound valve-control. Experimental evaluations demonstrate that the proposed solutions are capable of automatically generating a sound valve-control for PMDs.

I. Introduction

Microfluidics bears the potential to revolutionize the fields of chemical synthesis and biological analysis [1]. Corresponding devices efficiently handle and process sample volumes in the nano-to pico-liter range and, by this, allow to automatically conduct complex applications such as protein crystallization, high-throughput screening in drug development, or single cell analysis [1], [2] using very small volumes of samples and reagents.