CHINESE researchers have developed a cheap but accurate and easy-to-use paper test that can determine a patient’s blood type in just 30 seconds.
In a study published in the US journal Science Translational Medicine, Zhang Hong and his colleagues from China’s Third Military Medical University said there is a need to develop “a simple and economical strategy” for fast blood grouping.
That’s because conventional approaches are “encumbered by long turnaround times, labor-intensive operation, and technical training requirements.”
Unlike conventional methods, the new paper-based test, however, classified samples into the common ABO and Rh blood groups in less than 30 seconds, Zhang said.
To create the test, researchers took advantage of chemical reactions between blood serum proteins and a widely available dye called bromocreosol green.
Each test paper strip was also equipped with antibodies that recognized different blood type markers, such as A or B antigens, which can be found on the surface of red blood cells.
When a drop of blood was applied, the results appeared as visual color changes in the observation window of the paper strip — teal if a blood group antigen was present in a sample and brown if not.
The presence of A or B antigens or both indicates a patient’s blood type is A, B, or AB, while the absence of both A and B antigens indicates blood type O, Zhang said.
The paper-based test was also able to detect antibodies in blood plasma, which can help determine a patient’s blood type in full details and only took about two minutes to complete.