title: Electrical method to quantify nanoparticle interaction with lipid bilayers.
abstract: Understanding as well as rapidly screening the interaction of nanoparticles with cell membranes is of central importance for biological applications such as drug and gene delivery. Recently, we have shown that "striped" mixed-monolayer-coated gold nanoparticles spontaneously penetrate a variety of cell membranes through a passive pathway. Here, we report an electrical approach to screen and readily quantify the interaction between nanoparticles and bilayer lipid membranes. Membrane adsorption is monitored through the capacitive increase of suspended planar lipid membranes upon fusion with nanoparticles. We adopt a Langmuir isotherm model to characterize the adsorption of nanoparticles by bilayer lipid membranes and extract the partition coefficient, K, and the standard free energy gain by this spontaneous process, for a variety of sizes of cell-membrane-penetrating nanoparticles. We believe that the method presented here will be a useful qualitative and quantitative tool to determine nanoparticle interaction with lipid bilayers and consequently with cell membranes.
authors.affiliation: Institute of Materials, École Polytechnique Fédérale de Lausanne, EPFL-STI-IMX-SuNMIL, Lausanne CH-1015, Switzerland.
authors.forename: Randy P
authors.initials: RP
authors.lastname: Carney
authors.forename: Yann
authors.initials: Y
authors.lastname: Astier
authors.forename: Tamara M
authors.initials: TM
authors.lastname: Carney
authors.forename: Kislon
authors.initials: K
authors.lastname: Voïtchovsky
authors.forename: Paulo H
authors.initials: PH
authors.lastname: Jacob Silva
authors.forename: Francesco
authors.initials: F
authors.lastname: Stellacci
mesh_terms: D000327:Adsorption; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D004563:Electrochemistry / Q000379:methods*; D008051:Lipid Bilayers / Q000737:chemistry* / Q000378:metabolism; D053758:Nanoparticles / Q000737:chemistry*; D010743:Phospholipids / Q000737:chemistry
chemical_list: D008051:Lipid Bilayers; D010743:Phospholipids