AVS 50th International Symposium
    Biomaterial Interfaces Friday Sessions
       Session BI+PS-FrM

Paper BI+PS-FrM8
Study of RGD Peptide and Fibronectin Adsorption on Polymer Surfaces Micropatterned by Cold Plasma and Ion Beams

Friday, November 7, 2003, 10:40 am, Room 318/319

Session: Plasma Methods for Bio-interfaces
Presenter: C. Satriano, University of Catania, Italy
Authors: C. Satriano, University of Catania, Italy
M. Manso, Joint Research Centre, Ispra, Italy
N. Giamblanco, University of Catania, Italy
G. Ceccone, Joint Research Centre, Ispra, Italy
D. Gilliland, Joint Research Centre, Ispra, Italy
F. Rossi, Joint Research Centre, Ispra, Italy
G. Marletta, University of Catania, Italy
Correspondent: Click to Email
Thin films of polycaprolactone (PCL) and polyhydroxymethylsiloxane (PHMS) were patterned by Ar@super +@ ions beams or cold microwave Ar plasmas through Ni masks. The dimensions of the patterns stripes and pitches were typically between 30 and 100 µm. In the case of Ar@super +@ irradiation, the two ion energies of 50 keV and 0.5 keV were used, with fluences ranging from 1x1014 to 5x1015 ions/cm@super 2@. For plasma irradiation, the samples were placed on a grounded or RF biased sample holder (-50V), for different times. The surface structure and composition changes were characterized by spatially resolved X-Ray Photoelectron Spectroscopy (XPS) and Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS). The surface roughness on the micro- and nanometer scale was determined by Atomic Force Microscopy (AFM). The surface charge and dispersive/polar forces distribution were determined by Zeta Potential (ZP) and Surface Free Energy (SFE) measurements respectively. Finally the change of thickness and visco-elastic properties of the films was investigated by the Quartz Crystal Microbalance with Dissipation monitoring (QCM-D) technique. The adsorption of RGD peptide sequences and fibronectin was investigated as a function of the different treatment parameters, including ion energy and dose. The in-situ kinetics of adsorption and modeling of the viscoelastic properties of the adsorbed layers were studied by using QCM-D technique, while the chemical structure and lateral distribution of the adlayers were characterized ex situ by Small Spot XPS, ToF-SIMS Imaging measurements and AFM. The results showed that selective patterning of the adsorbed peptide and fibronectin could be achieved mainly in connection with the polar to dispersive ratio of the surface free energy. In particular, the surface modification seems to affect also the morphology adlayers.