Question

Match the images and the steps of ELISA

a. A substrate is present which the enzyme cleaves and colored reaction is produced
b. Enzyme linked antibody binds to specific antibody.
c. Blood serum from the patient is added and incubated for 30 minutes(wash)
​d. The well is first coated with a antigen and then washed

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

If a person has AIDS then he will produce antibodies against it which is usually IGg.So in this experiment this antibody is detected.
First the ELISA plate is coated with a antigen and then washed to remove unbound antigen.
Then the Patient serum is extracted and added to the well which will have IGg present in them if the patient is infected.This is allowed to incubated for sometime and then washed to remove antibody which have bound to the walls of the well and not the antigen.
Now an enzyme linked anti IGg is added and allowed to bind to the IGg from the blood serum sample.And then the well is washed again.Now a substrate is present in the well which will react with the enzyme and produce a colored reaction.And if the colored reaction does not occur then it means no antibodies were present in blood plasma and the person does not have AIDS.