Enhanced biocompatibility of porous Nitinol

Porous Nitinol (PNT) material has found vast applications in the medical industry as inter-body fusion devices, synthetic bone grafts, recombinant human bone morphogenetic protein, etc.  However, nickel release from PNT is anticipated to be greater as compared to nitinol wires or stents in the human body since there is a larger surface area in contact with body fluids. Furthermore, surface preparation is known to play a major role in a material’s biocompatibility. This study addresses the biocompatibility and corrosion resistance of passivated and unpassivated PNTs as well as electropolished and un-electropolished PNTs.  ASTM potentiodynamic and potentiostatic in vitro corrosion tests were conducted to evaluate the corrosion resistance in biological media. The growth of endothelial cells on various surface treated PNTs and their morphologies were observed using optical microscopy, SEM/EDS and Raman Spectroscopy.