A device as the size of a Ping-Pong ball can extract a small blood sample while held against the skin for two minutes which may make blood sampling less painful and more convenient. 

A slight vacuum in the device enables a small sample of blood to flow into an attached sample tube, which can be mailed or handed to a laboratory and users report that the process is almost entirely painless.

Scientists at the University of Wisconsin-Madison (WI, USA) developed the device that can extract about 0.15 mL of blood , which is enough to test cholesterol levels, infection biomarkers, cancer cells and blood glucose. The technology relies on the forces that govern the flow of tiny fluid streams.

The device is being perfected by Tasso Inc. (Madison, WI, USA). The company, whose name means "badger" in Italian, has applied for a patent on channels that create capillary action to move blood toward the sample tube. Ben Casavant, PhD, the vice president and co-founder of the company, said, “The technology relies on the forces that govern the flow of miniscule liquid streams. At these scales, surface tension dominates over gravity, and that keeps the blood in the channel no matter how you hold the device.” 

Dr. Casavant added, “Although diabetics must test their blood sugar several times a day, they are not an initial market. We see our specialty as people who need to test semi-frequently or infrequently, to monitor cancer or chronic infectious diseases, for example. Instead of buying a machine or expensive equipment, we ship you this device, you put it on your arm for two minutes and send it back to the laboratory.” The device could help those who fear blood draws, and avoid time-consuming trips to laboratory for blood draws.