2- ELISA

Question 1

What is an ELISA ?

Answer 1

Enzyme linked immunosorbent assay

Question 2

What are ELISA’s used for?

Answer 2

ELISA is a technique using antibodies and colour change to identify the concentration of an antigen in a mixture

Question 3

What are the two types of ELISA?

Answer 3

Direct and Indirect

Question 4

Why is a solution of non reacting protein added to the plate?

Answer 4

To block any unbound sites to prevent non-specific binding of the antibody
(block sites to stop the antibody sticking to them)

Question 5

What is an example of a non reacting protein that may be added?

Answer 5

Bovine serum albumin or powdered milk

Question 6

What causes the colour change to the solution?

Answer 6

Caused by the substrate breaking down in the enzyme and releasing a coloured product

Question 7

What does a colour change show?

Answer 7

That the enzyme is present, without the enzyme the antibody also wouldn’t be present

Question 8

What makes the colour change stronger?

Answer 8

The higher the concentration of the antibody the stronger the colour change