(180e) Interactions Between Lipid Bilayers and Carbon-Based Nanoparticles

In this talk, we present results of coarse-grained molecular dynamics (MD) simulations of interactions between dipalmitoylphosphatidylcholine (DPPC) lipid membranes and carbon-based nanoparticles (carbon nanotubes and fullerenes). Understanding these interactions is important for development of biomimetic devices and assessment of potentially harmful effects of nanomaterials on living cells. The considered nanoparticles are hydrophobic and therefore they tend to reside in the interior of the lipid bilayer. It is observed that these nanoparticles may affect several physical properties of the membrane, including its bending modulus, spontaneous curvature, and the lateral pressure profile. Fluctuations of tilt of the lipid molecules are also affected in the direct neighborhood of the nanoparticles. In addition, we observe that the dynamics of the thermal fluctuations of the membrane is significantly affected by the nanoparticles, especially when the latter approach the border between the hydrophilic head-groups and the hydrophobic tail-groups of the lipids.

The information obtained from MD simulations is used to construct a meso-scale model for lipid vesicles with nanoparticles embedded in their membranes. This model is used to assess possibility of the nanoparticle-induced membrane instability. The talk is concluded by a discussion of possible effect of the embedded nanoparticles on biophysical processes in cellular membranes.