Disease is an enemy of mankind; and we have been trying to avoid or combat with it. While as in all other wars, intelligence plays an important role in this war against disease. We human beings have developed many means to investigate and detect the information of diseases, and in-vitro diagnostic (IVD) medical test kits based on immunoassay principle is a prominent example of them. Thanks to the complex mechnism of our body immune system, if any virus intrudes into our body, or any change in the body function, the immune system will try to combat with this intrusion or change. And antibody is one weapon. This antibody will bind to the virus antigen, and make the latter to lose its function. In this way, it will help to get rid of bad effect of the virus. Immunoassay is based on the reaction between antigen and antibody.
For example, if we can detect the antibody in the human body fluid (serum, urine etc.), we can say that the tested person is infected or was infected with certain disease. In order to detect the antibody, we may fix antigens on a substrate, and then another antigen labeled with dye staff. When we first add specimen from the testee to the substrate, the target antibody will bind to the fixed antigens; and when we add the labeled antigen as marker too, the labeled antigen will be captured on the substrate. The dye stuff can be treated to show certain color, proving the presence of the target antibody. If no target in the specimen, the antigens labeled with dye stuff just move away, and no color will develop, indicating a negative result.
Considering that an estimated 60% to 70% of healthcare and clinical decision is based on IVD testing results, such as IVD disease diagnostics and health status testing, IVD medical diagnostic testing represents a cornerstone of human health promotion and maintenance. And the IVD testing devices market is still under the process of expanding, due to its low cost and rapidity of the testing procedure.