Which lipoprotein electrophoresis method depends on both charge and molecular size?

Which lipoprotein electrophoresis method depends on both charge and molecular size?

• A. Polyacrylamide gel
• B. Paper
• C. Cellulose acetate
• D. Agarose

Answer: (A)

Electrophoretic separation depends on two factors: the net charge of the particle and how easily it can move through the medium, which is influenced by size. A polyacrylamide gel forms a fine, crosslinked network that acts like a molecular sieve. Larger lipoprotein particles are hindered more than smaller ones, so their migration is slowed in a way that reflects their size. At the same time, the overall charge of each lipoprotein affects its direction and rate of movement. This combination means migration patterns in polyacrylamide gel electrophoresis reflect both charge and molecular size, making it the method that best depends on both properties. In contrast, paper and cellulose acetate provide relatively simple, charge-driven movement with less size discrimination, and agarose—while useful for many biomolecules—lacks the same fine sieving that highlights size differences for lipoproteins.

Electrophoretic separation depends on two factors: the net charge of the particle and how easily it can move through the medium, which is influenced by size. A polyacrylamide gel forms a fine, crosslinked network that acts like a molecular sieve. Larger lipoprotein particles are hindered more than smaller ones, so their migration is slowed in a way that reflects their size. At the same time, the overall charge of each lipoprotein affects its direction and rate of movement. This combination means migration patterns in polyacrylamide gel electrophoresis reflect both charge and molecular size, making it the method that best depends on both properties. In contrast, paper and cellulose acetate provide relatively simple, charge-driven movement with less size discrimination, and agarose—while useful for many biomolecules—lacks the same fine sieving that highlights size differences for lipoproteins.