An entire laboratory at the size of a credit card
Microelectronic chips combine the function of many transistors and diodes and thus constitute powerful tools for computations. Likewise, microfluidic chips combine many functions of a chemical laboratory and allow us to control tiny amounts of chemical solutions to perform assays, reactions, separations and many other (bio)chemical processes on a very small scale. This is just like having an entire laboratory sitting in the palm of your hand, and that is why such systems are often called lab-on-a-chip systems.
Imagine moving solutions through channels as thin as a human hair - interesting things happen on such a length scale. Water behaves almost like honey, streams go alongside each other like colored stripes in toothpaste, and cells can be manipulated one by one for investigation. I will explain some of the underlying principles and show how these devices can help us to better understand diseases, make new therapies possible, and reduce animal tests of new pharmaceuticals.