Citation
Ye, S. H.; Johnson, C. A.; Woolley, J. R.; Snyder, T. A.; Gamble, L. J.; & Wagner, W. R. (2009). Covalent surface modification of a titanium alloy with a phosphorylcholine-containing copolymer for reduced thrombogenicity in cardiovascular devices. Journal of Biomedical Materials Research Part A, 91A(1), 18-28.Abstract
Our objective was to develop a surface modification strategy for a titanium alloy (TiAl(6)V(4)) to provide thromboresistance for surfaces in rigorous blood-contacting cardiovascular applications, such as that found in ventricular assist devices. We hypothesized that this could be accomplished by the covalent attachment of a phospholipid polymer, poly(2-methacryloyloxyethylphosphorylcholine (MPC)-co-methacryl acid) (PMA). TiAl(6)V(4) was H(2)O plasma treated by radio frequency glow discharge, silanated with 3-aminopropyltriethoxysilane (APS), and ammonia plasma treated to increase surface reactivity. The TiAl(6)V(4) surface was then modified with PMA via a condensation reaction between the amino groups on the TiAl(6)V(4) surface and the carboxyl groups on PMA. The surface composition was verified by X-ray photoelectron spectroscopy, confirming successful modification of the TiAl(6)V(4) surfaces with APS and PMA as evidenced by increased Si and P. Plasma treatments with H(2)O and ammonia were effective at further increasing the surface reactivity of TiAl(6)V(4) as evidenced by increased surface PMA. The adsorption of ovine fibrinogen onto PMA-modified surfaces was reduced relative to unmodified surfaces, and in vitro ovine blood contact through a rocking test revealed marked reductions in platelet deposition and bulk phase platelet activation relative to unmodified TiAl(6)V(4) and polystyrene controls. The results indicate that the PMA-modification scheme for TiAl(6)V(4) surfaces offers a potential pathway to improve the thromboresistance of the blood-contacting surfaces of cardiovascular devices. (C) 2008 Wiley Periodicals, Inc. J Biomed Mater Res 91A: 18-28, 2009Keyword(s)
Biomedical applicationsblood compatibilitycardiovascular devicescellulose-acetatecoated stentscoronary-arteriesphospholipid polymerplatelet activationprotein-adsorptionreductionstainless-steelsurface modificationtitanium alloyNotes
492BATimes Cited:17
Cited References Count:54