Biologically Functionalized Expanded Polytetrafluoroethylene Blood Vessel Grafts

Abstract

Cardiovascular diseases plague human health due to the lack of transplantable small-diameter blood vessel (SDBV) grafts. Although expanded polytetrafluoroethylene (ePTFE) has the potential to be used as a biocompatible material for SDBV grafts, long-term patency is still the biggest challenge. As discussed in this paper, by virtue of a novel material formulation and a new and benign alcohol/water lubricating agent, biofunctionalized ePTFE blood vessel grafts aimed at providing long-term patency were fabricated. Compared to the most prevalent modification of polytetrafluoroethylene (PTFE), namely surface treatment, this method realized bulk treatment, which could guarantee homogeneous and long-lasting performance throughout PTFE products. These blood vessel grafts included embedded functional biomolecules, such as arginylglycylaspartic acid (RGD), heparin, and selenocystamine (SeCA), using water as a solvent in paste extrusion and in the expansion of ePTFE. Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM) results confirmed the existence of those targeting biomolecules in the as-fabricated ePTFE blood vessel grafts. Meanwhile, the greatly improved biological functions of the grafts were demonstrated via live and dead assays, cell morphology, CD31 staining, nitric oxide (NO) release, and anticoagulation tests. This novel and benign material formulation and fabrication method provides an opportunity to produce multi-biofunctional ePTFE blood vessel grafts in a single step, thus yielding a potent product with significant commercial and clinical potential.