title: Effect of silica nanoparticles on the interfacial properties of a canonical lipid mixture.
abstract: The incorporation of silica nanoparticles (NPs) from the subphase into Langmuir lipid monolayers formed by three components, 1,2-Dipalmitoyl-sn-glycerol-3-phosphocholine (DPPC), 1,2-Dioleoyl-sn-glycero-3-phosphocholine (DOPC) and Cholesterol (Chol), modifies the thermodynamic and rheological behavior, as well as the structure of the pristine lipid film. Thus, the combination of structural characterization techniques, such as Brewster Angle Microscopy (BAM) and Atomic Force Microscopy (AFM), with interfacial thermodynamic and dilational rheology studies has allowed us to deepen on the physico-chemical bases governing the interaction between lipid molecules and NPs. The penetration of NPs driven by the interaction (electrostatic or hydrogen bonds) with the polar groups of the lipid molecules affects the phase behaviour (surface pressure-area, П-A , isotherm) of the monolayer. This can be easily rationalized considering the modification of the packing and cohesion of the molecules at the interface as revealed BAM and AFM images. Furthermore, oscillatory barrier experiments have allowed obtaining information related to the effect of NPs on the monolayer response under dynamic conditions that presents a critical impact on the characterization of biological relevant systems because most of the processes of interest for these systems present a dynamic character.
authors.affiliation: CNR-Istituto per l'Energetica e le Interfasi, UOS Genova, Via De Marini 6, 16149 Genova, Italy. Electronic address: eduardogs@quim.ucm.es.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Guzmán
authors.affiliation: CNR-Istituto per l'Energetica e le Interfasi, UOS Genova, Via De Marini 6, 16149 Genova, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Ferrari
authors.affiliation: CNR-Istituto per l'Energetica e le Interfasi, UOS Genova, Via De Marini 6, 16149 Genova, Italy.
authors.forename: Eva
authors.initials: E
authors.lastname: Santini
authors.affiliation: CNR-Istituto per l'Energetica e le Interfasi, UOS Genova, Via De Marini 6, 16149 Genova, Italy.
authors.forename: Libero
authors.initials: L
authors.lastname: Liggieri
authors.affiliation: CNR-Istituto per l'Energetica e le Interfasi, UOS Genova, Via De Marini 6, 16149 Genova, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Ravera
mesh_terms: D008055:Lipids / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D012212:Rheology; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D008055:Lipids; D012822:Silicon Dioxide
keywords: Atomic Force Microscopy; Canonical mixture; Langmuir monolayers; Lipids; Nanoparticles