1. By: Patti, Naida, Angelica, Yuanyuan, and Harper
Radioimmunoassays
By: Patti, Naida, Angelica, Yuanyuan, and Harper

2. What are they and how do they work?
The known antigen is made radioactive and is mixed with an antibody from that antigen. They then bind together and a serum with an unknown amount of that same antigen is added, which then causes the unknown antigen from the serum to fight with the radioactive antigen for the antibody binding sites. As more of the unknown antigen is produced, more if it binds with the antibody, taking the radioactive antibody's place. This then decreases the ration of the antibody-bound radioactive antigen to free the radioactive antigen.The antigens-bound ones are separated from the unbound ones and the radioactivity of the free antigens remain and can then be detected.

3. This is how it works…

4. The Strengths
Radioimmunoassays can carefully and accurately detect antigens with very small samples because immune reactions are highly sensitive.
It uses high tech equipment in order for the immune reactions to be specific
It still remains cheaper than other options.

5. The Weaknesses
Because radioactive materials and radio-labeled reagents are being used, it can be harmful if exposed to it.
The disposal of it can be just as dangerous because it can only be disposed in certain places and in certain ways.
This test requires specially trained people, a license to handle radioactive material, and storage of radioactive material and radioactive waste.

6. The First Case Custody case in New York State(October 28,1988)
A woman (Ninni Burgel) seeking custody of her children, was forced to provide hair samples to show if she quit using cocaine
Requested by her husband Frank Burgel
First case to use this test/process
Radioimmunoassay can trace cocaine located within hair
“Based on theory that cocaine fossilizes in a users hair and that as the hair grows it can provide a ‘calendar’ of cocaine use”
Combines radiation and antibodies
It can trace the smallest amount of cocaine(one-millionth the size than in other chemical tests)
Court prevented her from doing anything to her in order to pursue the tests

7. The Second Case
August 1972-January Burear of Biologics gave “four panels of 20 coded serum samples” to blood banks in order to test for the hepatitis B antigen
Banks used two methods:
-CEP-counterelectophoresis
-RIA-radioimmunoassay
Results:
CEP:63 to 83% were correct; RIA: 98 to 100%
CEP:5 to 25% received perfect scores; RIA:77 to 100%
CEP:0.5 to 25% weren’t able to reproduce the same results from the samples; RIA:0 to 5%
Shows how this test is more dependable

8. 1.What were some of the dangers posed by radioimmunoassay?

9. A: Radiation could be harmful to people if handled improperly so there are health and safety risks, especially when it comes to disposal of the test materials.

10. 2.In the custody case in NY, how did radioimmunoassay find cocaine?

11. A: It combined radiation and antibodies to find traces of cocaine in her hair.

12. 3.Why did blood banks start to use radioimmunoassay?

13. A: The banks used it to test for the Hepatitis B antigen

14. 4. How sensitive is radioimmunoassay in testing for drugs in the serum?

15. A: Radioimmunoassay is sensitive to as low as 10 to 100 parts per billion

16. 5. What kind of data can radioimmunoassay testing provide?

17. A: It can provide both qualitative and quantitative data.

18. Sources: