IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Biomaterials Monday Sessions
       Session BI-MoP

Paper BI-MoP13
Surface Technologies to Optimize Osteopontin-immobilized Surfaces for Healing Biomaterials

Monday, October 29, 2001, 5:30 pm, Room 134/135

Session: Biorecognition Poster Session
Presenter: R. Ganapathy, University of Washington
Authors: S.M. Martin, University of Washington
R. Ganapathy, University of Washington
T. Kim, University of Washington
L.A. Martinson, University of Washington
D. Leach-Scampavia, University of Washington
S.L. Golledge, University of Washington
C. Giachelli, University of Washington
B.D. Ratner, University of Washington
Correspondent: Click to Email
Our efforts to develop biomaterial surfaces that modulate the healing and inflammatory response focus on immobilizing specific biological triggers of healing onto a bland, relatively non-protein adsorptive surface. This study illustrates the use of surface analysis tools to characterize such surfaces. Osteopontin (OPN) is a protein known to regulate inflammatory responses. Although its precise role is not fully understood, it has been implicated in wound-healing processes. We have thus chosen OPN as the protein to immobilize in these model experiments. ESCA data in our laboratory demonstrated that poly(2-hydroxyethyl methacrylate) (pHEMA) shows low protein adsorption, making it a suitable material for our immobilization studies. In the present study, a technique using carbonyldiimidazole (CDI) was used to immobilize OPN to the polyHEMA surface. We employed several techniques to verify presence of protein on the polyHEMA surface (ESCA, TOF-SIMS, FTIR) and quantified the amount immobilized (ELISA, radioiodination of OPN). ESCA high-resolution N 1s spectra indicated existence of OPN on the surface, and this data was confirmed by TOF-SIMS. Furthermore, data using I-125-labeled OPN showed a dose-response corresponding to the varying amounts of OPN used for the immobilization experiment. Though less accurate than the radiolabel data, the ELISA showed protein amounts in a similar range as well. These findings represent an important first step toward the creation of novel healing materials for biomedical applications and to using modern surface analytical tools to verify the surface engineering of a biomaterial. Studies funded by UWEB, EEC9529161.