Enzyme-linked immunosorbent assay technique is based on the principal of interaction between

Options

A. DNA and DNA probe
B. RNA and RNA probe
C. antigen-antibody
D. antigen and RNA

Answer

**Step-by-Step Solution:**

1. **Understanding ELISA**: The Enzyme-linked Immunosorbent Assay (ELISA) is a widely used laboratory technique for detecting and quantifying substances such as proteins, hormones, antibodies, and antigens.

2. **Principle of ELISA**: The fundamental principle behind ELISA is the specific interaction between an antigen and an antibody. Antigens are substances that can induce an immune response, while antibodies are proteins produced by the immune system to identify and neutralize foreign objects like bacteria and viruses.

3. **Mechanism of Action**: In an ELISA test, a sample containing the target antigen is added to a plate coated with a specific antibody. If the target antigen is present, it will bind to the antibody on the plate. This binding is the key interaction that ELISA relies on.

4. **Detection**: After the antigen binds to the antibody, a secondary enzyme-linked antibody is added. This secondary antibody binds to the antigen, forming a complex. A substrate is then added that the enzyme can convert into a detectable signal (such as a color change). The intensity of the signal is proportional to the amount of antigen present in the sample.

5. **Conclusion**: Therefore, the ELISA technique is based on the principle of interaction between antigen and antibody.

**Final Answer**: The Enzyme-linked Immunosorbent Assay technique is based on the principle of interaction between antigen and antibody.

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