Often cell populations are analysed by looking at average values of a population, such as size, shape and expression of proteins. However, a cell population is not homogeneous; it consists of different individual cells with different responses to stimuli.
Microfluidic technologies are a perfect tool to analyse the properties of individual cells. For example, the beating of individual spermatozoa can be measured by using electrical impedance measurements or optical analysis. More valuable information is present in the data, but this is currently not used.