Question

Which is more polar? Phosphatidylethanolamine or phosphatidylcholine when separating them using Thin Layer chromatography? And why? Please explain why it is more polar, in terms of its structure.

Answer 1

Ans. The choline group bears a +1 charge surrounded by three hydrophobic methyl groups. The ethanolamine group also has a positively charged amino group, but only one hydrophobic methyl group.

# So, presence of three hydrophobic methyl groups in phosphatidylcholine makes it relatively more hydrophobic than ethanolamine.

In other words, because of having a single hydrophobic methyl group (compared to three in phosphatidylcholine), phosphatidylethanolamine is more hydrophilic than phosphatidylcholine.