What kind of testing is used to determine the blood type based on the presence of antigens?

The hemagglutination test is a key method used to determine blood type, as it involves mixing a sample of blood with specific antibodies that correspond to certain antigens present on the surface of red blood cells. When the antigens from the blood cells react with the antibodies, agglutination or clumping occurs, which indicates a positive reaction for that particular blood type.

In this test, the presence of specific antigens, such as A and B antigens, is crucial for identifying whether the blood is type A, B, AB, or O. The visibility of clumping helps clinicians and laboratory technicians to accurately ascertain an individual's blood type and is particularly important for safe blood transfusions and organ transplants.

Other testing methods mentioned do not specifically determine blood type through antigen-antibody interactions. Electrophoresis, for example, is used for separating molecules based on size and charge, while culture tests involve growing organisms in vitro, and serological tests encompass a broader range of antibody detection methods rather than focusing solely on blood typing.