Droplet-based microfluidics

Droplet-based microfluidic systems generate, manipulate and control sub-microlitre droplets enclosed within an immiscible carrier fluid. Owing to a number of remarkable features, such as the ability to precisely control the chemical and biological payload of each droplet and to produce thousands of droplets per second, this technology is transforming how chemists and biologists perform high-throughput or massively parallel experiments. In this Primer, we initially introduce and describe the basic features of droplet-based microfluidic systems and key issues that should be considered when developing new chemical and biological workflows. We provide a critical evaluation of how droplet-based microfluidic systems should be manufactured and the importance of integrating appropriate detection technologies to probe the small analytical volumes that are representatives of the technology set. We then discuss issues related to data collection and management, providing guidelines on how large data sets should be processed and manipulated. Furthermore, we showcase some of the most successful and important applications of droplet-based systems in the biological and chemical sciences and consider issues that currently hinder progress in both technology development and application. Finally, we provide some opinion on future directions for the technology set and where its greatest impact will be felt in the coming years. Droplet-based microfluidic systems generate microlitre droplets, giving users precise control over the chemical and biological contents of each droplet. In this Primer, Moragues et al. discuss the optimal use of droplet-based microfluidic systems and the most successful applications in biological and chemical sciences.