(469a) Nanoparticle Induced Rupture of Lipid Bilayers

Interactions of nanoparticles (NP) with lipid bilayers (LB), which constitute the foundation of cell membranes, play an important role in emerging nanotechnologies. At the same time, NP encapsulation may lead to destabilization of LBs, raising multiple health-related concerns regarding NP toxicity. Tension-induced rupture of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) lipid membranes with encapsulated spherical and cylindrical NPs is studied using dissipative particle dynamics (DPD) simulations. A nanoparticle size dependent relationship is established for the probability of membrane rupture within given time as a function of the membrane surface tension. Two mechanisms of hole formation are explored: nucleation far from the NP and nucleation near the NP. The NP induced nucleation is treated in terms of an original theoretical model by introducing an effective contact angle on the three-phase, solvent-membrane-solid, boundary into the Derjuigan-Gutop theory.