Dual biofunctional polymer modifications to address endothelialization and smooth muscle cell integration of ePTFE vascular grafts

Abstract

Expanded polytetrafluoroethylene (ePTFE) grafts were coated on the luminal surface with a cell-adhesive fluorosurfactant (FSP) polymer to promote endothelialization, followed by ethanol hydration to degas the pores and subsequent cell-adhesive, enzymatically degradable poly(ethylene glycol)-based hydrogel incorporation into the graft interstices to accommodate potential smooth muscle cell integration in the graft wall. The FSP coating on ePTFE was stable as demonstrated by a significantly reduced receding water contact angle on FSP-coated ePTFE (14.5 ± 6.4°) compared to uncoated ePTFE (105.3 ± 4.5°, P < 0.05) after ethanol exposure. X-ray photoelectron spectroscopy analysis of the same surfaces confirmed FSP presence. Localization of the FSP and hydrogel within the ePTFE graft construct was assessed using fluorescently labeled polymers, and demonstrated hydrogel infiltration throughout the thickness of the graft wall, with FSP coating limited to the lumen and adventitial surfaces. FSP at the luminal surface on dual-coated grafts was able to bind endothelial cells (EC) (98.7 ± 23.1 cells/mm(2) ) similar to fibronectin controls (129.4 ± 40.7 cells/mm(2) ), and significantly higher than uncoated ePTFE (31.6 ± 19 cells/mm(2,) P < 0.05). These results indicate that ePTFE grafts can be simultaneously modified with two different polymers that have potential to directly address both endothelialization and intimal hyperplasia. Such a construct is a promising candidate for an off-the-shelf synthetic graft for small-diameter graft applications.

Mechanical and microstructural analysis of a radially expandable vascular conduit for neonatal and pediatric cardiovascular surgery

“…Similarly, no group had a significant difference in the network OI [ Figure 5(D)] in pre-and postexpansion. The node and fiber topology of ePTFE; 41,43 results from material processing and is not a function of expansion, thereby making similar fiber network alignment pre and postexpansion desirable. While the entire fiber network appears to be highly aligned, the algorithm evaluates both the nodes and the fiber edges which are 90 degrees apart and results in a reduced magnitude of fiber alignment.…”

Semifluorinated Alkanes as New Drug Carriers—An Overview of Potential Medical and Clinical Applications

“…Microporous expanded PTFE (ePTFE or better known as GoreTex ® ) is used in reconstructive surgery, especially for intravascular bypass grafts. F-alkyl groups can modify the surface of polymers, including ePTFE, reduce thrombogenicity and friction, protect against enzymatic degradation and enhance the adhesion and growth of certain cells [38][39][40].…”

Selection of different endothelialization modes and different seed cells for tissue-engineered vascular graft

“…To solve the problem of intimal hyperplasia and thrombosis of TEVGs, the coating modified on TEVGs is a feasible method. Studies have shown that the use of fluorosurfactant (FSP) or heparin coating can inhibit the intimal hyperplasia and thrombosis of ePTFE vascular grafts effectively [ 41 ]. The patency rate of polyurethane (PU) vascular grafts modified by heparin and cell-adhesive peptides was significantly higher than that of unmodified PU vascular grafts after 9 weeks of implantation [ 42 ].…”