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What is Elek's gel precipitation test used for diagnosing: and explain in detail?
Elek's gel precipitation test is an example of double diffusion in two dimensions. It is used to demonstrate C. dipthariae. Precipitation band: If the strain is toxigenic, the toxin diffuses in the agar, meets with the antitoxin and produces arrow-shaped precipitation band. Nontoxigenic stain will not produce any precipitation line. The precipitate lines would fuse with each other if the toxins produced by die strains are identical.