ELASTICITY OF BILAYERS CONTAINING PEG LIPIDS

The addition of lipids with a poly(ethylene glycol) head group (Stealt h or grafted or PEG lipids) to a phosphatidylcholine bilayer changes t he mechanical properties of the membrane. We calculate the dependences of the bending and stretching elasticities of the bilayer on the PEG lipid concentration and on the monomer number in its polymer chain. Th e role of the bending elasticity at blocked flip-flop of the pure bila yer is revealed.