Coarse-grained molecular dynamics simulation of tethered lipid assemblies

Using coarse-grained molecular dynamic simulations based on the MARTINI force field, we study the self-assembly of free dipalmitoylphosphatidylcholine (DPPC) lipids onto PEGylated lipids tethered to a solid substrate. We show that upon increasing lipid concentration, structural transitions occur from tethered spherical nanoparticles, to tethered cylinders and bicelles, to a tethered lipid bilayer with pores, to an unporated tethered lipid bilayer, and finally to a tethered lipid bilayer with liposomes on top of it. The simulation results compare well with structures inferred from experimental observations. In addition, we demonstrate the structural stability and local fluidity of the tethered lipid bilayer.