title: Study of interactions between polymer nanoparticles and cell membranes at atomistic levels.
abstract: Knowledge of how the structure of nanoparticles and the interactions with biological cell membranes is important not only for understanding nanotoxicological effects on human, animal health and the environment, but also for better understanding of nanoparticle fabrication for biomedical applications. In this work, we use molecular modelling techniques, namely molecular dynamics (MD) simulations, to explore how polymer nanoparticles interact with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipid cell membranes. Two different polymers have been considered: 100 monomer units of polyethylene (approx. 2.83 kDa) and polystyrene (approx. 10.4 kDa), both of which have wide industrial applications. We found that, despite the polar lipid head groups acting as an effective barrier to prevent the nanoparticles from interacting with the membrane surface, irreversible adhesion can be initiated by insertion of dangling chain ends from the polymer into the hydrophobic interior of the membrane. In addition, alignment of chain segments from the polymers with that of hydrocarbon chains in the interior of the membrane facilitates the complete immersion of the nanoparticles into the cell membrane. These findings highlight the importance of the surface and the topological structures of the polymer particles that dictate the absorption behaviour into the membrane and, subsequently, induce the possible translocation into the cell.
authors.affiliation: Scientific Computing Department, Science and Technology Facilities Council, Daresbury Laboratory, Sci-Tech Daresbury, Warrington WA4 4AD, UK Manchester Pharmacy School, Faculty of Medical and Human Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK chin.yong@sftc.ac.uk.
authors.forename: Chin W
authors.initials: CW
authors.lastname: Yong
mesh_terms: D002448:Cell Adhesion / Q000502:physiology*; D002462:Cell Membrane / Q000737:chemistry / Q000502:physiology*; D008958:Models, Molecular; D053758:Nanoparticles / Q000737:chemistry*; D010713:Phosphatidylcholines / Q000737:chemistry*; D011108:Polymers
chemical_list: D010713:Phosphatidylcholines; D011108:Polymers; C028694:1-palmitoyl-2-oleoylphosphatidylcholine
keywords: cell membrane; molecular dynamics; polyethylene; polymer nanoparticle; polystyrene; surface adhesion