EPTFE polytetrafluoroethylene

One other material that is used for its limited cell adhesion feature is expanded pol-ytetrafluoroethylene (ePTFE). Polytetrafluoroethylene (PTFE) was launched in the 1940s by Du Pont de Nemours as Teflon brand name. PTFE was used for the first time as a vascular prosthesis in 1963 by Edwards Lifescience and then in 1970s by Gore-Tex in expanded and microporous form (Fig. 13.12). Polytetrafluoroethylene is very stable chemically and has high hydrophobic grade that provides reduced throm-bogenicity compared to material such as PET. However, ePTFE-related mechanical properties are very poor with low compliance and elasticity. 

Polytetrafluoroethylene suture is composed of expanded polytetrafluoroethylene (ePTFE), resulting in a porous microstructure having longitudinally oriented nodes and fibrils. The suture is sold by W. L. Gore Associates, Inc. under the trade name Gore-Tex Suture. 

More recently, W. L. Gore Associates, Inc. [31] have used expanded polytetrafluoroethylene (ePTFE) porous films and PFSA resin solutions to produce a composite membrane. In this process, the PFSA solution was brushed onto both sides of the ePTFE film so as to impregnate and substantially occlude the interior volume of the film a nonionic surfactant (5%, w/v) was then added into the PFSA solution as a penetrant. The surfactant was removed by soaking in isopropanol after drying at 140 °C (this procedure was repeated several times so as to fully occlude the interior... 

I. Baek, C.Z. Bai, J. Hwang, J. Park, J.S. Park, D.J. Kim, Suppression of neointimal hyperplasia by sirolimus-eluting expanded polytetrafluoroethylene (ePTFE) haemodialysis grafts in comparison with paclitaxel-coated grafts, Nephrol. Dial. Transplant. 27 (2012) 1997-2004. 

Fig 1 22 Boston Scientific Endotak quadripolar Reliance G implantable cardioverter-defibrillator lead. Two expanded polytetrafluoroethylene (ePTFE or Gore-Tex) jackets black arrows) cover the shock coils to prevent tissue ingrowth (courtesy of Boston Scientific)... 

Surface topographic features on the micron scale were shown to influence the fate of neutrophils by activating either non-apoptotic, or apoptotic cell death. Shive et al. [44] revealed that neutrophils underwent a rapid apoptosis on a polye-therurethane urea film even when they were exposed to physiological level of shear stress. Chang et al. [45] have shown that neutrophils cultured on roughened polytetrafluoroethylene (ePTFE) resulted in non-apoptotic cell death by the release of reactive oxygen species, while neutrophils adhered to smooth polystyrene remain viable. 

Polytetrafluoroethylene (PTFE, Teflon, Fluorel) is best known for its excellent chemical stability and low coefficient of friction. Expanded PTFE (ePTFE) contains micropores created by stretching PTFE film and is used in small-diameter vascular grafts and for artificial heart valve sewing rings... 

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