TINY electronic devices known as a “lab-on-a-chip” are now routinely used to analyse small biological samples, sometimes a few microlitres or less, and to carry out out other tasks such as purifying proteins and DNA. Some even reproduce the functions of a complete organ, like a kidney or lung, so that they can be used to test drugs reliably and cheaply.
Many of these devices, though, end up not so little because of the bulky ancillary parts and chunky bits of tubing required to pump fluids in and out of the chips. This can limit their application. What would be good is a way to make the complete system more portable—or, indeed, wearable so that the devices can be used to test patients regularly. That means shrinking the external paraphernalia down to a size more comparable to the chip itself.