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, performs two key roles in protein electrophoresis. It denatures proteins by disrupting non-covalent interactions, unfolding them into linear chains. Additionally, it coats proteins with a uniform negative charge proportional to their size. This dual action ensures that separation during SDS-PAGE relies solely on molecular weight, eliminating influence from protein shape or intrinsic charge.