Structural and Functional Regulation of Self-Assembled Molecular Membrane formed by Amphiphilic Graft Peptide

Abstract

Molecular membranes of the amphiphilic graft peptide (PAAgPLLeu) consisted of polyallylamine main chain and hydrophobic poly(L-Leu) graft chains, as a model of lipid molecules were prepared at water-water interface. Under acidic conditions, PAAgPLLeu formed a regular and dense thin molecular membrame, with the poly(L-Leu) graft chains took a β-sheet structure at the water-water interface. Under this condition, the molecular membrane shows chiral selectivity for an amino acid having the same optical activity as the graft chains of the amphiphilic copolymer. The permeability of L-Leu through the nano-sheet was 26 times greater than that of D-isomer.