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Öğe Enhanced biocompatibility of GPC by ion implantation and deposition(Elsevier Science Sa, 2007) Zimmerman, R.; Guerhan, I.; Muntele, C.; Ila, D.; Rodrigues, M.; Oezdal-Kurt, F.; Sen, B. H.Biocompatible Glassy Polymeric Carbon (GPC) is used for artificial heart valves and in other biomedical applications. Although it is ideally suited for implants in the blood stream, tissue that normally forms around the moving parts of a GPC heart valve sometimes loses adhesion and creates embolisms downstream. We have previously shown that oxygen ion implantation slightly enhances cell adhesion to GPC. Here we compare silver ion implantation and silver deposition, each of which strongly inhibits cell attachment on GPC. Inhibition of cell adhesion is the more desirable improvement to current GPC cardiac implants. In vitro biocompatibility tests have been carried out with model cell lines to demonstrate that traces of silver can favorably influence the surface of GPC for biomedical applications. (c) 2007 Published by Elsevier B.V.Öğe The influence of ion implantation on cell attachment to glassy polymeric carbon(Amer Inst Physics, 2006) Zimmerman, R.; Gurhan, I.; Ozdal-Kurt, F.; Sen, B. H.; Roigues, M.; Ila, D.; Kirkby, KJ; Chivers, D; Gwilliam, R; Smith, AIn vitro biocompatibility tests have been carried out with model cell lines to demonstrate that near surface implantation of silver in Glassy Polymeric Carbon (GPC) can completely inhibit cell attachment on implanted areas while leaving adjacent areas unaffected. Patterned ion implantation permits precise control of tissue growth on medical applications of GPC. We have shown that silver ion implantation or argon ion assisted surface deposition of silver inhibits cell growth on GPC, a desirable improvement of current cardiac implants.Öğe Investigation of cell growth on ion beam patterns on GPC surface(Elsevier Science Sa, 2009) Zimmerman, R.; Muntele, C.; Gurhan, I.; Ozdal-Kurt, F.; Sen, B. H.; Rodrigues, M.; Ila, D.We have used implanted silver ions near the surface of Glassy Polymeric Carbon (GPC) to completely inhibit cell attachment and adhesion to GPC. The effect improves the safety and function of the GPC heart valve exposed to the blood stream. The strength, durability and low density make GPC a favored material for in vivo medical applications, including transcutaneous electrodes and replacement heart valves. However, the possible release of endothelial tissue that forms on the smooth surfaces of the GPC heart valve has the potential of creating an embolism. We have shown that L929 endothelial cells avoid silver implanted areas of GPC but attach and strongly adhere to areas close to silver implanted surfaces. Patterned ion implantation permits precise control of tissue growth on GPC and other biocompatible substrates. Cell growth inhibited by silver ion implanted patterns on an otherwise biocompatible substrate may be useful for in vitro studies of the way that cells sense and move away from inhospitable environments. (C) 2009 Published by Elsevier B.V.Öğe Ion implantation inhibits cell attachment to glassy polymeric carbon(Elsevier Science Bv, 2007) Zimmerman, R.; Deliloglu-Gurhan, I.; Ozdal-Kurt, F.; Sen, B. H.; Rodrigues, M.; Ila, D.Implantation of MeV gold, oxygen, carbon ions into GPC alters the surface topography of GPC and enhances the already strong tendency for cells to attach to GPC. We have shown that implantation of silver ions near the surface strongly inhibits cell growth on GPC. Both enhanced adhesion of and inhibition of cell growth are desirable improvements on cardiac implants that have long been successfully fabricated from biocompatible glassy polymeric carbon (GPC). In vitro biocompatibility tests have been carried out with model cell lines to demonstrate that ion beam assisted deposition (IBAD) of silver, as well as silver ion bombardment, can favorably influence the surface of GPC for biomedical applications. (c) 2007 Elsevier B.V. All rights reserved.Öğe Nano- and micro-structural evolution of UHMWPE by ion beam(Materials Research Soc, 2007) Calzzani, F.; Chhay, B.; Zimmerman, R.; Oztarhan, A.; Ila, D.; Ila, D; Baglin, J; Kishimoto, N; Chu, PKIt is important to produce uniform nano-patterns with no possibility of surface exfoliation on polyethylene devices used in medical and in aerospace industry. We studied the change in the surface morphology of polyethylene at nanoscale using MeV ion beam. We have investigated the change in the surface morphology before and after ion bombardment. We have made an attempt to change the morphology to produce a uniform surface with reduced cracks and reduced granularity. For this process we have chosen ultra-high-molecular-weight polyethylene (UHMWPE). Coupons of these materials were exposed to various fluences of MeV Ag+ ions. The surface morphology and the change in the chemical structure were studied using scanning micro Raman, FTIR and AFM.
