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Home List of Titles Adsorption and enzymatic cleavage of osteopontin at interfaces with different surface chemistries
Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/198477
- Adsorption and enzymatic cleavage of osteopontin at interfaces with different surface chemistries
- Malmstrom, Jenny; Shipovskov, Stepan; Christensen, Brian; Sorensen, Esben S.; Kingshott, Peter; Sutherland, Duncan S.
- Osteopontin is a highly charged glycoprotein present in the extra cellular matrix of a wide range of tissues. It is, in particular, relevant for biomaterials through its role in mineralized tissue remodeling. The adsorption and enzymatic cleavage of osteopontin at four different surface chemistries (methyl-, carboxylic-, and amine-terminated alkanethiol self-assembled monolayers and bare gold) have been studied utilizing a combination of the quartz crystal microbalance with dissipation and surface plasmon resonance. Full length bovine milk osteopontin was used which is well characterized with respect to post-translational modifications. Osteopontin adsorbed at all the surfaces formed thin (~2-5 nm) hydrated layers with the highest amount of protein and the highest density layers observed at the hydrophobic surface. Less protein and a higher level of hydration was observed at the polar surfaces with the highest level of hydration being observed at the gold surface. The energy dissipation of these thin films (as measured by the ΔD/ΔF value) was altered at the different surface chemistries and interestingly a higher dissipation correlated with a higher density. Thrombin was able to bind and cleave the surface bound osteopontin at the hydrophobic surface. The altered levels of osteopontin binding, hydration of the layer, and susceptibility to thrombin cleavage suggest that osteopontin adopts different conformations and/or orientations at the different material surfaces.
- Publication type
- Journal article
- Biointerphases, Vol. 4, no. 3 (Sep 2009), pp. 47-55
- Publication year
- FOR Code(s)
- 0299 Other Physical Sciences; 0303 Macromolecular and Materials Chemistry
- American Vacuum Society
- Publisher URL
- Copyright © 2009 American Vacuum Society.
- Peer reviewed