It takes between 10 and 20 minutes to verify the type of blood we have (A, B, AB or O), not including the time it takes to transport the blood to a laboratory.
However, a paper test that identifies the blood group con just a few drops of blood and in a few seconds It has been developed by scientists from the Third Military Medical University in Chongqing (China).
The green tint of bromocreosol (basically a dye that interacts with blood) has been included in a test strip with antibodies that recognized different blood type markers, the antigens. The paper strip appeared in bluish green if an antigen from a particular blood group was in the sample and in brown if it was not.
The color change occurs in 30 seconds and looks like a thermometer. The researchers analyzed 3,550 blood samples and had an accuracy rate of 99.9%. The study has been published in the journal Science Translational Medicine.