Partitioning of 1-alkanols in composite raft-like lipid membrane

Abstract

Though 1-alkanols are well known to have anesthetic properties, the mode of operation remains enigmatic. We perform extensive atomistic molecular dynamics simulation to study the partitioning of 1- alkanols of different chain-lengths in raft-like model membrane made up of mixture of unsaturated dioleoyl-phosphatidylcholine (DOPC) and saturated dipalmitoyl-phosphatidylcholine (DPPC) and choles- terol (Chol) exhibiting phase coexistence of liquid-ordered (lo) - liquid disordered (ld) phase domains. Our simulation shows that the effect of 1-alkanols on the mechanical properties of the membrane has been pronounced with the chain-length of it. In particular, the 1-alkanols prefer to partition in the ld phase domain. The penetration of the 1-alkanols in the membrane increases significantly for the long-chain alkanol. We also have found the dependency of the order of chains of the lipids and rigidity of the membrane on the 1-alkanols.