title: Fibronectin adsorption on gold, Ti-, and Ta-oxide investigated by QCM-D and RSA modelling.
abstract: The adsorption of fibronectin on gold, Ti-, and Ta-oxide surfaces is investigated by means of the quartz crystal microbalance with dissipation (QCM-D) technique. The surface chemistry (gold, Ti-, and Ta-oxide) is found to influence the frequency shift observed during adsorption of the fibronectin layer with the magnitude being Delta f Au>Delta f Ti-oxide approximately Delta f Ta-oxide. Corresponding variations in the dissipation change normalised to frequency change (Delta D/Delta f) for the layer are observed. The QCM-D data are further analyzed by the random sequential adsorption (RSA) model, and adsorption rate parameter ka and footprint (a) determined, which supported the trend seen in the Delta f and Delta D/Delta f values. The value of ka found by the RSA modelling of the QCM-D resonance frequency data is found to match the ratio between the mass measured by QCM-D and the mass reported by optical techniques in literature. We conclude that comparison of the adsorption rate parameter (ka) obtained by RSA modelling of the QCM-D data with ka values obtained from RSA modelling of data obtained using optical techniques can be a route to determine the degree of hydration of the adsorbed protein layer.
authors.affiliation: Interdisciplinary Nanoscience Center and Department of Physics and Astronomy, University of Aarhus, 8000 Aarhus C, Denmark.
authors.forename: Anne Gry
authors.initials: AG
authors.lastname: Hemmersam
authors.forename: Kristian
authors.initials: K
authors.lastname: Rechendorff
authors.forename: Morten
authors.initials: M
authors.lastname: Foss
authors.forename: Duncan S
authors.initials: DS
authors.lastname: Sutherland
authors.forename: Flemming
authors.initials: F
authors.lastname: Besenbacher
mesh_terms: D000327:Adsorption; D005353:Fibronectins / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D006801:Humans; D010087:Oxides / Q000737:chemistry*; D011791:Quartz / Q000737:chemistry; D013499:Surface Properties; D013635:Tantalum / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D005353:Fibronectins; D010087:Oxides; D011791:Quartz; D013635:Tantalum; D006046:Gold; D014025:Titanium; C078151:tantalum oxide