By encapsulating a small number of bacterial cells within microfluidic droplets and observing the response of these cells to their environment, we are able to make quantitative measurements on the behavior of the cells in time. Furthermore by working within an array of sationary droplets, we are able to repeat the experiments hundreds or thousands of times in parallel. This ability to obtain detailed statistics of any behavior that is observed allows us to address questions on microbiology from a probabilstic perspective. By combining with mathematical models of cell behavior, we gain access to subtle variations between individual cells or colonies.
Applications of this approach are being developed to observe the emergence of resistance to antibiotics, or to detect naturally occurring heterogeneities between individual cells.