Design and realization of flexible droplet-based lab-on-a-chip devices: From theory to practice

This article provides an overview on the emerging field of droplet-based microfluidic networks. In such networks, droplets i.e., encapsulating biochemical samples can be adaptively transported via microchannels through different operations for particular experiments. This approach is particularly promising for the next generation of lab-on-a-chip devices, which should support more complex operations and more flexibility. We give an accessible introduction to droplet-based microfluidics and describe the principles, of microfluidic switches, which are the main components in microfluidic networks. Based on these principles we present the addressing schemes for microfluidic bus networks. Since the design of microfluidic networks is a rather complex task, which requires the consideration of a huge number of physical parameters, we introduce design automation methods and simulation tools. Finally, we present a method for the precise generation of individual droplets, which enables the practical realization of microfluidic networks. Moreover, we show the latest experimental results on droplet generation and switching.