ELISA technique is based on -

The correct answer is Option (1) → Antigen-Antibody interactions

ELISA stands for enzyme linked immuno-sorbent assay. It is a test for the early diagnosis of an infection. It works on the antigen-antibody interaction: an antibody binds only to its own antigen. So an infection can be found either by detecting the antigens of the pathogen (proteins, glycoproteins and so on) or by detecting the antibodies made against the pathogen. ELISA is a widely used test for AIDS.

(1) Antigen-Antibody interactions — Correct. This is the principle on which ELISA works.

(2) DNA-Protein interactions — Incorrect. ELISA does not detect DNA. Methods such as PCR and DNA probes are used to detect nucleic acids.

(3) Protein synthesis — Incorrect. ELISA does not make any protein. It detects proteins that are already present.

(4) RNA interference — Incorrect. RNA interference is a way of silencing a particular mRNA. It is not a diagnostic test.

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NCERT Extract:
Molecular Diagnosis – …