BIO13 - Comprehensive Results Of Protein Adsorption, Platelets Adhesion, And Blood Clot Formation on the DLC-Coated Surface of ePTFE Vascular Graft
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2022-06-01 |
| Journal | ASAIO Journal |
| Authors | Yasuhiro Fujii, Takashi Goyama, Tatsuyuki Nakatani, Daiki Ousaka, Yuichi Imai |
| Institutions | Okayama University, Okayama University of Science |
Abstract
Section titled āAbstractāBackground: Expanded polytetrafluoroethylene (ePTFE) vascular graft is currently the gold standard for small arterial bypass and hemodialysis vascular access because ePTFE is the fabric with the best hemocompatibility and patency in these situations to date. Recently, we developed a new technology to coat diamond-like carbon (DLC) to the inner surface of resin tubes with the expectation that DLC would improve the hemocompatibility of the material surface; however, no comprehensive study about DLC on a resin tube such as ePTFE has been conducted. This study aimed to obtain comprehensive basic data about the hemocompatibility of DLC-coated ePTFE to support the start of DLC application to vascular grafts and other resin medical tubular devices. Methods: The internal surfaces of ePTFE artificial vascular grafts was coated with DLC using an alternating current high-voltage methane plasma chemical vapor deposition system (Figure 1), and several hemocompatibility tests (Water angle test to see hydrophilicity, scanning electron microscope to see surface smoothness, protein adsorption tests, platelet adhesion tests, and whole blood contact tests) were performed. Results: DLC made ePTFE fibers more hydrophilic (decreased water angle, P<0.01) and smoother in appearance as observed by a scanning electron microscope (SEM). In addition, SEM showed that peeling of the DLC coating did not occur with the anastomosis maneuver. SDS-PAGE examination showed that protein adsorption was increased in almost all protein molecular size categories in the DLC-coated ePTFE graft. DLC-coated ePTFE increased albumin and fibrinogen adsorption (P<0.01) and decreased platelet adhesion (P<0.01). In the whole blood contact test, there was no thrombus formation with in vitro human blood and in vivo rat (replacement of the aorta), beagle (replacement of the carotid artery), and goat blood (arteriovenous shunt) in both types of ePTFE grafts. In all these implanting studies, the patency was comparable. However, there was a thin fibrin layer on the DLC-coated ePTFE after in vitro and in vivo whole blood contacts, which is a consistent finding with the in vitro protein adsorption test. Conclusions: In conclusion, several in vivo studies have shown that the hemocompatibility of a DLC-coated ePTFE graft is as good as that of normal ePTFE, despite the increased protein adsorption including fibrinogen. These results indicate that DLC coating can be used on less hemocompatible materials to improve their hemocompatibility to the ePTFE level. In addition, the newly developed DLC may be useful as an undercoating of vascular grafts or other tubular resin materials for the drug or cell attachment technology because it does not lead to an impairment of graft function.