Radial immunodiffusion

Radial immunodiffusion (also known as Mancini method, Farr assay, or single radial immunodiffusion assay) is a common laboratory technique used to quantify the concentration of antigens (such as proteins) in a sample. The method was first described by Mancini, Carbonara, and Heremans in 1965.

Principle

Radial immunodiffusion involves the diffusion of antigens through a gel that contains specific antibodies. The antigen diffuses from a well into the gel, forming a circular precipitate. The diameter of this circle is directly proportional to the concentration of the antigen in the sample.

Procedure

The procedure for radial immunodiffusion involves several steps:

1. A gel is prepared with a specific antibody.
2. Wells are cut into the gel.
3. The sample is added to the well.
4. The gel is incubated to allow for antigen-antibody interaction.
5. The diameter of the precipitate is measured.

Applications

Radial immunodiffusion is used in various fields, including:

1. Immunology: to quantify specific proteins in a sample.
2. Clinical pathology: to diagnose and monitor diseases.
3. Research: to study antigen-antibody interactions.

Limitations

While radial immunodiffusion is a useful technique, it has several limitations:

1. It is not suitable for measuring low concentrations of antigens.
2. It requires specific antibodies for each antigen.
3. It is time-consuming and requires careful handling.

See also

• Immunodiffusion
• Immunoprecipitation
• Ouchterlony double diffusion

References

• Radial immunodiffusion
• Absolute myocardial blood flow
  Absolute myocardial blood flow
• Cavity numbers increase exponentially with sugar consumption
  Cavity numbers increase exponentially with sugar consumption