Western blot

Definition

Western blot is a lab technique used to detect specific proteins in a sample through gel electrophoresis and antibodies. It is widely utilized for confirming the presence of viral proteins and immune responses.

5 Must Know Facts For Your Next Test

1. Western blotting involves separating proteins based on their molecular weight using gel electrophoresis.
2. After separation, proteins are transferred onto a membrane, usually made of nitrocellulose or PVDF.
3. Primary antibodies are used to bind to the target protein, followed by secondary antibodies that enable detection.
4. The technique can be used to confirm the results of an ELISA test by verifying the presence of specific antigens or antibodies.
5. Western blot is crucial in diagnosing infections like HIV by detecting viral proteins.

Review Questions

• What is the primary purpose of Western blot in a laboratory setting?
• How are proteins separated in Western blotting before they are transferred onto a membrane?
• Why might Western blot be used as a follow-up test after an ELISA?

Related terms

ELISA:

Enzyme-Linked Immunosorbent Assay, a test that uses antibodies and color change to identify a substance.

Antibody:

A protein produced by the immune system that binds specifically to an antigen.

Gel Electrophoresis:

A method for separating molecules (like DNA or proteins) based on size and charge using an electric field.