What is Ouchterlony double diffusion method?
Ouchterlony double immunodiffusion (also known as passive double immunodiffusion) is an immunological technique used in the detection, identification and quantification of antibodies and antigens, such as immunoglobulins and extractable nuclear antigens.
What is the reaction of Ouchterlony double diffusion?
Double Immuno-diffusion It is a special precipitation reaction on gels where antibodies react with specific antigens forming large antigen-antibody complexes which can be observed as a line of the precipitate. In double immunodiffusion, both the antibody and antigen are allowed to diffuse into the gel.
What are the limitations of Ouchterlony?
In the absence of staining, the Ouchterlony double immunodiffusion assay is sensitive to 100ug/ml of specific antibody, however a limitation of the technique is that is requires high concentrations of both antigen and antibody and are relatively insensitive to antibodies with low affinities (Hornbeck 1991).
Why is double diffusion important?
Double diffusion convection plays a significant role in upwelling of nutrients and vertical transport of heat and salt in oceans. Such mixing helps regulate the gradual overturning circulation of the ocean, which control the climate of the earth.
What is the principle of Ouchterlony?
This procedure was developed by Örjan Ouchterlony. Principle: When soluble antigen and antibody samples are placed in adjacent wells in agarose gel, they diffuse radially into the agarose gel and set up two opposing concentration gradients between the wells.
Why is ouchterlony called double diffusion?
In the Ouchterlony double diffusion, both the antigen and the antibody diffuse toward each other in a semisolid medium to a point till their optimum concentration is reached. A band of precipitation occurs at this point.
When two antigens are identical their Precipitin lines form?
Identity: It occurs when two antigens share identical epitopes. As the antiserum forms a single precipitin line with each antigen, the two lines grow toward each other and fuse to give a single curved line of identity. 2. Nonidentity: It occurs when two antigens are unrelated (i.e. share no common epitopes).
Why is immunodiffusion used?
Immunodiffusion tests are usually performed to support the diagnosis when the initial EIA is positive. Immunodiffusion tests measure precipitin-type antibodies (reported as IgG antibodies). These are less sensitive than EIAs but more specific.
What is single immunodiffusion?
Single Radial Immunodiffusion is a technique used extensively for the quantitative estimation of antigens. Antibody of known specificity is distributed evenly in an agar gel and a sample containing the antigen of interest is placed in a well within the gel.