As if tumbling down an artificial waterfall, this video shows a stream of bacteria cells flowing into a network of tiny man-made channels. The channels are made from PDMS, a transparent polymer also found in silly putty. Each bend and twist has been carefully engineered to guide the cells in solution into the rectangular compartments (on the right), which measure less than 1/1000 cm across. This microfluidic device doesn’t rely on gravity to control the flow but pressure. By lowering the pressure on one side of the device relative to the other, the cells are ‘pulled’ across the channels. Then comes the really clever bit – by adding different chemicals into different compartments, a wide range of experiments is possible. The lives of millions of cells can be watched from above. It’s no wonder that these devices, built onto chips roughly the size of a credit card, are revolutionising cell biology research.
Written by John Ankers
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.