Effect of C60 nanoparticles on elasticity of small unilamellar vesicles composed of DPPC bilayers*

Abstract

The interaction between C60 nanoparticles and biomembranes has been of great interest in researches over the past decades due to their novel applications as well as potential cytotoxicity. In this work, we study the deformation of the small unilamellar vesicles composed of dipalmitoylphosphatidylcholine (DPPC) lipid bilayers infiltrated with C60 nanoparticles of different molecular concentrations through coarse-grained molecular dynamics simulations. By employing the Helfrich spontaneous curvature model, the bending modulus and the spontaneous curvature of the vesicles with C60 nanoparticles of different concentrations are obtained according to the simulation data. The results show that the bending modulus and the spontaneous curvature of pure DPPC vesicle membranes are approximately 1.6 × 10−19 J and 1.4 nm−1, respectively. Both of them increase linearly approximately as the C60 concentration increases from 0 to 16.3%. The density profiles of vesicles, the order of lipid packing and the diffusion characteristics of DPPC and C60 are also investigated.