Molecular dynamics study of changes in physico-chemical properties of DMPC lipid bilayers by addition of nonionic surfactant C12E10

摘要

Changes in physico-chemical properties of dimyristoyl phosphatidylcholine (DMPC) lipid bilayers caused by the addition of 9.4mol% nonionic surfactant decaoxyethylene monododecyl ethers (C12E10) have been investigated by molecular dynamics calculations. In spite of addition of single chain C12E10, the lipid bilayers showed an increase of membrane area. Isothermal area compressibility, which is a measure of membrane softness in lateral direction, also increased by 50% for DMPC/C12E10 mixed bilayers. Furthermore, the order parameter of C-H vector for DMPC acyl tails decreased. We found that these changes are caused by the hydrophilic head groups of C12E10 which are located near the glycerol backbone of the DMPC molecules and have bulky random coil conformation without any preferential ordered structures.