AVS 53rd International Symposium
    Nanometer-scale Science and Technology Thursday Sessions
       Session NS+BI-ThM

Paper NS+BI-ThM9
Surface Nanostructuring using Colloidal Particles for Improved Biocompatibility

Thursday, November 16, 2006, 10:40 am, Room 2016

Session: Biological and Molecular Applications of Nanoscale Structures
Presenter: C.J. Nonckreman, Université Catholique de Louvain, Belgium
Authors: C.J. Nonckreman, Université Catholique de Louvain, Belgium
P.G. Rouxhet, Université Catholique de Louvain, Belgium
Ch.C. Dupont-Gillain, Université Catholique de Louvain, Belgium
Correspondent: Click to Email
Nanostructured surfaces offer new perspectives in different fields of application, including the design of biomaterials (implants, catheters, blood bags). The aim of this work is to create model surfaces presenting bimodal roughness characteristics (scales of 500 nm and 50 nm) using colloidal lithography. An appropriately designed nanoroughness is expected to modulate the effect of the surface chemical composition for controlling the interactions of cells and tissues with materials. Colloidal lithography was performed using adsorption of cationic polymers and adhesion of negatively charged colloidal particles. Polyallylamine hydrochloride was used to confer a positive charge to a glass substrate. On this conditioned surface, a layer of colloids (polystyrene latex) was formed owing to electrostatic attraction. Sequential steps of polycation adsorption and particle adhesion were applied on the substrate, which was then analyzed by scanning electron microscopy. Adjustment of conditions for incubation solutions (concentration, pH and ionic strength), rinsing and drying were tested in order to produce a high surface coverage with colloids and to minimize their aggregation. Thereby, a range of surface structures was obtained: layer of particles with a diameter of 470 nm, layer of particles with a diameter of 65 nm, bimodal roughness made by particles with a diameter of 65 nm on the top of particles with a diameter of 470 nm. The obtained surfaces are conditioned by adsorption of compounds which make them protein repellent, in particular Pluronic F68, a block copolymer of polypropylene oxide and polyethylene oxide. The surfaces finally obtained are being tested with respect to plasma protein adsorption, in particular competitive adsorption of fibrinogen and albumin, and to biocompatibility.