Question

What is the role of sodium dodecyl sulfate (SDS) in protein electrophoresis?
(A) Add net negative charge to the protein
(B) Separate lipids on the basis of their molecular weight
(C) Modify native conformation of a protein
(D) Allows direct destaining of the proteins
Choose the correct answer from the options given below:

• A. (A), (B), and (D) only
• B. (A) and (C) only
• C. (A), (B), (C), and (D)
• D. (B) and (D) only

Hint:

Focus on how SDS alters protein conformation and charge during electrophoresis.

Answer 1

The Correct Option is B

SDS, an anionic detergent, plays a dual role in protein electrophoresis. It denatures proteins by breaking non-covalent interactions, thus unfolding them into linear chains. It also coats proteins with a uniform negative charge proportional to their size, ensuring that the separation during SDS-PAGE is based solely on molecular weight rather than shape or charge.