W. Soboyejo, Princeton University, Princeton, NJ
Multi-Scale RGD Coated Surfaces for Biomedical Applications: Cell/Surface Interactions and Cell Adhesion
J. Chen, C. Milburn, E. Paetzell, R. Bly, W. Moore, S. Agonafer and W.O. Soboyejo
Princeton Institute of Science and Technology of Materials, and the Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544
Abstract
This paper presents RGD-coated biomedical surfaces for the improvement of cell attachment and Osseo integration. These include Ti, Co-Cr and Si surfaces that are relevant to orthopedics, dentistry, tissue engineering and bio-micro-electro-mechanical systems (BioMEMS). The RGD coating procedure is shown to apply to metallic (Ti and Co-Cr) and non-metallic (Si) surfaces that form surface oxides upon exposure to air. The coatings are also shown to form on flat, laser textured and porous surfaces with a range of architectures. In each of these cases, the results of cell spreading and adhesion studies are presented. The studies of cell spreading reveal that RGD coatings enhance the rate of cell spreading, adhesion and cytoskeleton organization and mineralization. The coatings are also shown to enhance the initial interfacial strengths between biomedical surfaces and human osteoblasts/human osteo-sarcoma cells, which are characterized on flat surfaces using shear assay experiments. Subsequently, the combined effects of surface texture and RGD coatings are explored using laser textured microgrooved silicon and titanium surfaces with different groove spacings. The RGD-coated microgroove geometries are shown to promote improved cell spreading and contact guidance, which is known to reduce scar tissue formation. Finally, cell/surface interactions are studied in micro-porous titanium structures with a range of pore sizes. In each of these structures, RGD coatings are shown to enhance the rate of cell spreading and proliferation. The adhesion between cells and the textured/porous surfaces is also quantified using micro-pipette aspiration. The implications of the results are then discussed for potential applications in orthopedics, dentistry, tissue engineering and BioMEMS.
Summary: This paper presents RGD-coated biomedical surfaces for the improvement of cell attachment and Osseo integration. These include Ti, Co-Cr and Si surfaces that are relevant to orthopedics, dentistry, tissue engineering and bio-micro-electro-mechanical systems (BioMEMS). The RGD coating procedure is shown to apply to metallic (Ti and Co-Cr) and non-metallic (Si) surfaces that form surface oxides upon exposure to air. The coatings are also shown to form on flat, laser textured and porous surfaces with a range of architectures. In each of these cases, the results of cell spreading and adhesion studies are presented. The studies of cell spreading reveal that RGD coatings enhance the rate of cell spreading, adhesion and cytoskeleton organization and mineralization. The coatings are also shown to enhance the initial interfacial strengths between biomedical surfaces and human osteoblasts/human osteo-sarcoma cells, which are characterized on flat surfaces using shear assay experiments. Subsequently, the combined effects of surface texture and RGD coatings are explored using laser textured microgrooved silicon and titanium surfaces with different groove spacings. The RGD-coated microgroove geometries are shown to promote improved cell spreading and contact guidance, which is known to reduce scar tissue formation. Finally, cell/surface interactions are studied in micro-porous titanium structures with a range of pore sizes. In each of these structures, RGD coatings are shown to enhance the rate of cell spreading and proliferation. The adhesion between cells and the textured/porous surfaces is also quantified using micro-pipette aspiration. The implications of the results are then discussed for potential applications in orthopedics, dentistry, tissue engineering and BioMEMS.
