title: Combination of collagen and fibronectin to design biomimetic interfaces: Do these proteins form layer-by-layer assemblies?
abstract: Layer-by-layer (LbL) assembly is a surface modification method which may bring complexity to biointerfaces designed to control cell-material interactions. This work aims at investigating the LbL assembly of two extracellular matrix proteins, collagen (Col) and fibronectin (Fn), on polystyrene substrates. LbL assembly, which is widely applied to polyelectrolytes, is not easily transferred to proteins. Different buffers and conditions are tested, and LbL assembly is compared to the simultaneous adsorption of Fn and Col. Build-up and properties of the films are monitored using quartz crystal microbalance, ellipsometry, water contact angle measurements, and atomic force microscopy. Results show that denatured Col leads to smoother films, and that the addition of a polyethyleneimine anchoring layer increases film thickness. A more regular construction and thicker films are obtained with Hepes (pH 7.4) compared to other buffers. However, the LbL assembly is not sustainable and stops after the deposition of a few layers. Films obtained by simultaneous adsorption have lower water contact angles, different morphologies, lower water content and are as thick or thicker compared to the ones prepared by the LbL method. The present work shows that collagen and fibronectin are not involved in a true LbL assembly process. The obtained biointerfaces however exhibit different properties compared to those obtained by the one-step adsorption of these proteins. These differences could be exploited to control cell fate.
authors.affiliation: Institute of Condensed Matter and Nanosciences, Université catholique de Louvain, Croix du Sud 1 (Bte L7.04.01), 1348 Louvain-la-Neuve, Belgium.
authors.forename: Sara
authors.initials: S
authors.lastname: Mauquoy
authors.affiliation: Institute of Condensed Matter and Nanosciences, Université catholique de Louvain, Croix du Sud 1 (Bte L7.04.01), 1348 Louvain-la-Neuve, Belgium. Electronic address: christine.dupont@uclouvain.be.
authors.forename: Christine
authors.initials: C
authors.lastname: Dupont-Gillain
mesh_terms: D000327:Adsorption; D000818:Animals; D032701:Biomimetics; D002417:Cattle; D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism; D003094:Collagen / Q000737:chemistry* / Q000378:metabolism; D005109:Extracellular Matrix / Q000737:chemistry* / Q000378:metabolism; D005353:Fibronectins / Q000737:chemistry* / Q000378:metabolism; D007124:Immunoenzyme Techniques; D008422:Materials Testing; D058525:Quartz Crystal Microbalance Techniques; D013499:Surface Properties
chemical_list: D005353:Fibronectins; D003094:Collagen
keywords: Adsorption; Biointerfaces; Collagen; Extracellular matrix; Fibronectin; Layer-by-layer