title: Interaction between dipolar lipid headgroups and charged nanoparticles mediated by water dipoles and ions.
abstract: In this work, a theoretical model describing the interaction between a positively or negatively charged nanoparticle and neutral zwitterionic lipid bilayers is presented. It is shown that in the close vicinity of the positively charged nanoparticle, the zwitterionic lipid head groups are less extended in the direction perpendicular to the membrane surface, while in the vicinity of the negatively charged nanoparticle, the headgroups are more extended.This result coincides with the calculated increase in the osmotic pressure between the zwitterionic lipid surface and positively charged nanoparticle and the decrease of osmotic pressure between the zwitterionic lipid surface and the negatively charged nanoparticle.Our theoretical predictions agree well with the experimentally determined fluidity of a lipid bilayer membrane in contact with positively or negatively charged nanoparticles. The prospective significance of the present work is mainly to contribute to better understanding of the interactions of charged nanoparticles with a zwitterionic lipid bilayer, which may be important in the efficient design of the lipid/nanoparticle nanostructures (like liposomes with encapsulated nanoparticles), which have diverse biomedical applications, including targeted therapy (drug delivery) and imaging of cancer cells.
authors.affiliation: SMARTEH Research and Development of Electronic Controlling and Regulating Systems, Trg tigrovcev 1, Tolmin SI-5220, Slovenia. aljaz.velikonja@avelik.homeip.net
authors.forename: Aljaž
authors.initials: A
authors.lastname: Velikonja
authors.forename: Poornima Budime
authors.initials: PB
authors.lastname: Santhosh
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Gongadze
authors.forename: Mukta
authors.initials: M
authors.lastname: Kulkarni
authors.forename: Kristina
authors.initials: K
authors.lastname: Eleršič
authors.forename: Šarka
authors.initials: Š
authors.lastname: Perutkova
authors.forename: Veronika
authors.initials: V
authors.lastname: Kralj-Iglič
authors.forename: Nataša Poklar
authors.initials: NP
authors.lastname: Ulrih
authors.forename: Aleš
authors.initials: A
authors.lastname: Iglič
mesh_terms: D007477:Ions / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008560:Membrane Fluidity / Q000502:physiology*; D008962:Models, Theoretical; D053758:Nanoparticles / Q000737:chemistry*; D009997:Osmotic Pressure / Q000502:physiology; D055672:Static Electricity; D014867:Water / Q000737:chemistry*
chemical_list: D007477:Ions; D008051:Lipid Bilayers; D014867:Water