In today’s field of modern medicine, knowing someone’s blood type is a very important piece of information. Whenever we might need a blood donor in case of emergencies, it’s vital to know your and the donor’s blood type before moving through the blood transfusion, because the consequences of transfusing the wrong blood type could be fatal. Not everyone has the luxury of knowing their blood types, however, especially those who live in remote or rural areas where testing labs aren’t available. That’s where these Chinese researchers from the Third Military Medical University in Chongqing come in: they have invented a blood type testing apparatus that only uses dye and color changing paper
Source: Daily Mail UK
Traditional blood typing is done with the aid of a centrifuge, a machine that spins blood within a tube to separate the blood’s components into layers. Remote areas do not have this equipment, so that’s where the researchers have put their focus towards: a blood test that doesn’t need a centrifuge.
The researchers worked around this by searching and collecting a kind of dye that interacts with blood, called bromocresol green. You see, what gives people different blood types are the kind of antigens and antibodies their red blood cells have around their membrane, and this dye changes color according to the antigens and antibodies found within the blood sample.
Source: Wikimedia Commons
The device, similar to a thermometer (or a pregnancy test) has two ends. The left end has a solution that contains antibody A and the right one has a solution that contains antibody B. Then, the user puts a few drops of blood at the center, along with a drop of the dye. The solution will seep into the paper to reach the antibody solutions. If the blood is type A, then the left solution containing antibody A would turn brown and the one right one with antigen B would turn teal. If the blood was type B, the left would turn teal and the right would turn brown. If the blood was AB, both solutions would become teal, whilst if the blood was O (a blood type without any antigens), both solutions would turn brown.
What’s great is that the solution only takes 30 seconds to change color, compared to lab tests that takes hours or even days. It’s also 99.9% accurate; and since the apparatus relies only on color change (which even red-green colorblind people can see), it’s easy for emergency responses and for people in remote areas to access and use.
The researchers plan on improving this technology by making sure it can work in different settings and environments, as well as detect rarer blood types (i.e. blood types with positive or negative Rh factors). In the meantime, the results look very promising, and this technology could be a big game changer in the medical field.