E-Mail An innovative new device which can examine and separate single cells on the basis of their response to stimuli could boost personalised medicine and advance our understanding of our own molecular mechanisms. Developed at the University of Exeter's Living Systems Institute, the Functional Phenotype Flow Cytometer (FPFC) moves individual cells between "virtually" separate microfluidic channels, thereby exposing them to a substance that can induce a cellular response. For the first time, it allows scientists to sort cells by their function, and by the strength of the response, in greater granularity than ever before. The research, published in Advanced Biology and funded by the BBSRC, with support from the Academy of Medical Sciences and the Swiss National Science Foundation, has potential to improve personalised medicine, by detecting whether a specific drug is likely to work for a patient before it is administered.