gel diffusion

diffusion /dif·fu·sion/ (dĭ-fu´zhun)

1. the process of becoming diffused, or widely spread.

2. the spontaneous movement of molecules or other particles in solution, owing to their random thermal motion, to reach a uniform concentration throughout the solvent, a process requiring no addition of energy to the system.

3. in hemodialysis, the movement of solutes across semipermeable membranes down concentration gradients.

4. immunodiffusion.

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double diffusion  an immunodiffusion test in which both antigen and antibody diffuse into a common area so that, if the antigen and antibody are interacting, they combine to form bands of precipitate.

gel diffusion  a test in which antigen and antibody diffuse toward one another through a gel medium to form a precipitate.

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gel diffusion.

See immunodiffusion.