Immunoelectron microscopy

Immunoelectron microscopy

It combines immunology technology and electron microscopy technology to develop a new type of serological detection method, that is, after labeling antibody with ferritin, it is used to detect the specimen to be tested, so that it penetrates into the cell and binds to the presence of The site of the antigen was fixed with osmium acid, and the section was embedded and examined with an electron microscope. The ferritin molecule shows clearly visible black particles under the electron microscope, so it can accurately show the location of the antigen, making its application reach the level of subcellular detection. In addition, there have also been reports of using enzyme-labeled antibodies to treat the specimens for immunoelectron microscopy, but the contrast under the electron microscope was not as clear as the ferritin-labeled antibodies.

In addition to the above two methods, colloidal gold-labeled antibody globulin can also be used to detect antigens and observed under an electron microscope. The colloidal gold technology is also called colloidal gold probes. It is a system of gold solution in which tiny gold particles of 1 ~ 100nm are dispersed in another solution, that is, the gold solution is used to mark Antibody globulin is used to check the specimen. Because it penetrates into the cell and binds to the corresponding antigen, it can be observed under an electron microscope. This technique was first used by Faulk and Taylor in 1971 to determine the surface antigen of Salmonella. In order to improve the sensitivity of the colloidal gold technology, Holgate combined the technology with the silver imaging method in 1983, and established the immunogoldsliver staining (IGSS). The principle is that the specimen is stained with gold-labeled protein and then used Silver developing solution treatment, that is, using hydroquinone to catalyze the reduction of silver ions into silver atoms. The silver atoms form a silver shell around the gold particles, so that the colloidal gold particles can be observed under the light microscope, and the visibility is improved.