Taking inspiration from leeches, a new device that painlessly draws blood without large needles has been developed by a team of scientists from ETH Zurich.

To painlessly and accurately draw blood samples, the new device uses a combination of microneedles and a suction cup.

Much like leeches — which attach themselves to the host’s skin and suck blood with their teeth from the wounded area, subsequently creating negative pressure by swallowing — the 2.5 centimeter long silicone suction cup component of the device is affixed to the arm or back of a patient. Within that suction cup are a series of steel microneedles that puncture the skin when the device is pushed.

Within just minutes, negative pressure within the suction cup ensures that an appropriate amount of blood can be collected for diagnostic testing, the device's developers explained.

In addition to being easy to handle and posing significantly low risk of injury, the team believes the device will be appropriate for use in low-income regions.

Further, because the microneedles are located within the suction cup, the risk of injury after disposal is also reduced compared to blood sampling with conventional needles.

An article detailing the device, “A Bioinspired and Cost-Effective Device for Minimally Invasive Blood Sampling,” was published in the journal Advanced Science.