Use of plasma glow for surface-engineering biomolecules to enhance bloodcompatibility of Dacron and PTFE vascular prosthesis

The search for a nonthrombogenic material having patency to be used for sma ll diameter vascular graft applications continues to be a field of extensiv e investigation. The purpose of the present study was to examine whether su rface modification of polytetra fluoroethylene (PTFE, Teflon) and polyethyl ene-terephthalate (Dacron) vascular grafts might extend graft biocompatibil ity without modifying the graft structure. A series of surface coatings wer e prepared by modifying the argon plasma-treated PTFE and Dacron grafts wit h collagen IV and laminin and subsequently immobilizing bioactive molecules like PGE(1), heparin or phosphatidyl choline via the carbodiimide function alities. Surface analysis by Fourier transform infrared spectroscopy-attenu ated total reflectance revealed the presence of new functional groups on th e modified graft surfaces. In vitro studies showed that fibrinogen adsorpti on and platelet adhesion on modified grafts were significantly reduced. Thi s study proposes that surface grafting of matrix components (collagen-type IV and laminin) and subsequent immobilization of bioactive molecules (PGE(1 ), heparin or phosphatidyl choline) changed the surface conditioning of vas cular grafts and subsequently improved their biocompatibility. However, mor e detailed in vivo studies are needed to confirm these observations. (C) 20 00 Elsevier Science Ltd. All rights reserved.