A study by Australian scientists has resulted in the development of a test for blood type that can be performed using antibody impregnated paper manufacturable for a few cents per test, which is significantly cheaper than existing tests of a similar nature. This could make all the difference in the developing world, considering it's essential to test for blood type before performing a blood transfusion on a patient whose blood type is unknown. The test essentially allows blood type to be determined based on the distance the blood travels along the channels in the paper from the point where it is dropped.
Whilst "home" blood test products already exist, being in the range of $10, they are potentially out of reach for people in developing countries. The new method has resulted in a prototype that allows ABO +/- blood type to be tested for in a single step with no mixing required and manufacturing costs of "a few cents per test." Why so low? Because the production process is simple: inkjet printing.
The prototype, developed at Monash University, Melbourne, involves three channels radiating from the center of the paper, each channel being treated with a different antibody. The way that each blood type spreads from the center of the paper along each channel varies due to the different way each blood type interacts with the antibodies, as, depending on the blood type, the antibodies have a different effect on the viscosity of the blood.
The results of the test become known after between 4 and 10 minutes, which, along with the low cost of manufacturing, make this a great boon for the medical community, especially in the developing world.
"With paper and printing been respectively the cheapest substrate and the most efficient manufacturing process, this test is a disruptive technology with cost orders of magnitude lower than alternatives," study co-author Professor Gil Garnier of the Australasian Pulp and Paper Institute told Gizmag. "It also offers a platform for other types of diagnostics and the ability to introduce more advanced signal amplification techniques."
The details of the study can be found in the paper titled "Paper Diagnostic for Instantaneous Blood Typing" in the journal Analytical Chemistry.