Hi-tech device combines with low-cost test for straightforward blood typing

Australian researchers developed a paper-based blood type test and a smartphone app to rapidly interpret the result. The test is simple enough to be used by non-experts and the smartphone link could help users at remote medical facilities.

Identifying a patient’s blood group correctly is crucial as giving them the wrong type can be fatal. This is because blood-type specific antibodies in the plasma trigger a strong immune response when they detect non-matching red blood cells.

In 2010, scientists created a simple blood group test by printing three hydrophobic microchannels onto tissue paper and loading them with different antibodies. Different blood types then travel different lengths along the channels. The device could distinguish the four blood types (A, B, AB and O) but not the Rh factors (positive or negative).

Wei Shen and his group from Monash University in Melbourne, Australia, have now extended the test to recognise all four blood types as well as the Rh factor. They also developed a smartphone app that reads the resulting barcode-like pattern using the camera, with the whole test taking only two minutes.