Changes

==Introduction==

==Introduction==

The radioimmunoassay (RIA) is a sensitive technique used to detect the presence of antigen in a sample using radiolabelled antibodies. Developed in the 1960's, the RIA proved a powerful tool in antigen detection, although the procedure was soon overtaken by ELISA, which utilises enzymes rather than radioactive labels. RIAs are still used today however, to measure:  

The radioimmunoassay (RIA) is a sensitive technique used to detect the presence of antigen in a sample using radiolabelled antibodies. Developed in the 1960's, the RIA proved a powerful tool in antigen detection, although the procedure was soon overtaken by ELISA, which utilises enzymes rather than radioactive labels. RIAs are still used today however, to measure:  

**RIA used in this way has been employed in the detection of the hepatitis B surface antigen in donor blood, reducing the occurrence of hepatitis infections as a result of blood transfusions in humans

**RIA used in this way has been employed in the detection of the hepatitis B surface antigen in donor blood, reducing the occurrence of hepatitis infections as a result of blood transfusions in humans

*Measuring plasma levels of hormones and controlled substances

*Measuring plasma levels of hormones and controlled substances

*Measuring anti-DNA antibodies present in systemic lupus erythematosus (SLE)

*Measuring anti-DNA antibodies present in [[SLE|systemic lupus erythematosus (SLE)]]

=Drawbacks=

==Drawbacks==

Although the RIA is a very sensitive test, and therefore widely-used, there are disadvantages to its use:

Although the RIA is a very sensitive test, and therefore widely-used, there are disadvantages to its use:

*The substances being used are radioactive

*The substances being used are radioactive

[[Category:Immunological Testing]]

[[Category:Immunological Testing]]