Question

The blotting technique used for separation of proteins is called

• A. Eastern blotting
• B. Southern blotting
• C. Western blotting
• D. Northern blotting

Answer 1

Answer: (C)

Western blotting

Answer 2

Western blotting is a widely used technique for the detection and analysis of proteins based on their ability to bind to specific antibodies. In Western blotting (immunoblotting) the protein mixture is applied to a gel electrophoresis in a carrier matrix ($SDS-PAGE$, native $PAGE$, etc.) to sort the proteins by size, charge, or other differences in individual protein bands. The separated protein bands are then transferred to a carrier membrane (e.g, nitrocellulose, nylon or $PVDF$). This process is called blotting. The proteins adhere to the membrane in the same pattern as they have been separated due to interactions of charges. The proteins on this immunoblot are then accessible for antibody binding for detection. Antibodies are used to detect target proteins on the western blot (immunoblot). The antibodies are conjugated with fluorescent or radioactive labels or enzymes that give a subsequent reaction with an applied reagent, leading to a colouring or emission of light, enabling detection.