One drop at a time: toward droplet microfluidics as a versatile tool for single-cell analysis

Applying droplet microfluidics to cells trapped within water-in-oil droplets offers a powerful way to study single cells in action. Wilhelm Huck and colleagues at Radboud University in the Netherlands have reviewed the application of this technique and research toward the study of individual cells. Unlike most cell analysis methods, it allows specific chemicals to be associated with the individual cell they come from or interact with. Researchers are currently addressing many technical challenges, including performing washing steps inside droplets and developing better ways to monitor and manipulate the cells at high-throughput rates. Current work is focused on reducing the complexity and enhancing the sensitivity of the technique. The authors also review applications that could soon become routine, including drug and antibody studies, tracking single-cell gene expression, studies of cell evolution and analysis of cellular interactions when droplets fuse.