ELISA Test

Question 1

What is ELISA?

Answer 1

Enzyme 
Linked
Immuno
Sorbent 
Assay

Question 2

What is an ELISA used for?

Answer 2

Testing whether patients have a specific antibody or antigen

Question 3

How do ELISAs give results?

Answer 3

They use antibodies bound to enzymes which when the complimentary substate is added a colour change can be observed

Question 4

What is a Direct ELISA?

Answer 4

• Test for antigens

- Immobilised antibodies are fixed to a well

Question 5

What is an Indirect ELISA?

Answer 5

• Test for antibodies

- Immobilised antigens are fixed to a well

Question 6

How is a direct ELISA carried out?

Answer 6

1 - Immobilised antibodies are fixed to a well
2- Sample added (blood plasma)
3- If blood plasma contains complementary antigens then an antigen-antibody complex will form
4- Rinse to remove unbound antigens
5- Same antibody with an enzyme is added
6- Rinse to remove unbound antibodies
7- Add substrate 
8- Observe

Question 7

How is an indirect ELISA carried out?

Answer 7

1 - Immobilised antigens are fixed to a well
2- Sample added (blood plasma)
3- If blood plasma contains complementary antibodies then an antigen-antibody complex will form
4- Rinse to remove unbound antibodies
5- Different antibody with an enzyme is added which will only bind if the first antibody is present
6- Rinse to remove unbound antibodies and enzymes
7- Add substrate
8- Observe