Immunodiffusion is a diagnostic test which involves diffusion through a substance such as agar which is generally soft gel agar (2%) or agarose (2%), used for the detection of antibodies or antigen.
The commonly known types are:
Single diffusion in one dimension (Oudin procedure)
Double diffusion in one dimension (Oakley Fulthorpe procedure)
↑"Radial Immunodiffusion". Edvotek, Inc. 2017. Archived from the original(photograph) on 2017-08-07. Retrieved 2017-08-07. Photograph of precipitin circles in a Petri dish during radial immunodiffusion.
↑"Diffusion Patterns". Immunodiffusion principles and application. Archived from the original on 2019-12-11. Retrieved 2017-05-19. Photographs of Ouchterlony immunodiffusion patterns showing stained precipitin lines of full identity, partial identity and non-identity.