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Cell adhesion study of the titanium alloys exposed to glow discharge
(Elsevier, 2007) Abidzina, V.; Deliloglu-Guerhan, I.; Ozdal-Kurt, F.; Sen, B. H.; Tereshko, I.; Elkin, I.; Budak, S.; Muntele, C.; Ila, D.
Titanium for biomedical application stems mainly from its advantageous bulk mechanical properties in combination with a high degree of biocompatibility that is largely attributable to their surface properties. This work is focused on the investigation of surface properties of treated titanium and cell adhesion to titanium treated in glow-discharge plasma. Pure titanium samples (grade 4) were exposed to low-energy ion irradiation in a specially constructed plasma generator, where materials were irradiated by ions of residual gases in vacuum. The ion energy was 1-10 keV. The irradiation dose was maintained at 10(17) ions cm(-2). The irradiation time varied from 5 to 60 min. Rutherford backscattering spectrometry (RBS) was used for surface studies. RBS showed the presence of iron on the titanium surface that occurred from the cathode of plasma generator. In vitro biocompatibility test have been carried out with model cell lines (L929 mouse fibroblasts) to demonstrate that low-energy ion irradiation can favorably influence the surface of titanium for biomedical application. Scanning electron microscopy (SEM) was the main tool to demonstrate the cell attachment properties. (c) 2007 Elsevier B.V. All rights reserved.
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.
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, A
In 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.
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.
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.
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, PK
It 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.
Nanoscale surface modification of UltraHigh Molecular Weight Polyethylene (UHMWPE) samples with the W plus C ion implantation
(Materials Research Soc, 2007) Urkac, E. Sokullu; Oztarhan, A.; Tihminlioglu, F.; Kaya, N.; Budak, S.; Chhay, B.; Muntele, C.; Oks, E.; Nikolaev, A.; Ila, D.; Ila, D; Baglin, J; Kishimoto, N; Chu, PK
In this work, Ultra High Molecular Weight Poly Ethylene (UHMWPE) samples Were implanted by W + C ions using Metal-Vapour Vacuum Arc (MEVVA) ion implantation system with a fluence of 10(17) ion/cm(2) and extraction voltage of 30 kV. Samples were characterized with Raman Spectra, ATR-FTIR, UV-VIS-NlR Spectrum and RBS. Surface morphology of implanted and unimplanted samples were examined in nanoscale with AFM.
Polymeric thermal analysis of C+H and C+H+Ar ion implanted UHMWPE samples
(Elsevier Science Bv, 2007) Kaya, N.; Oztarhan, Ahmet M.; Urkac, E. S.; Ila, D.; Budak, S.; Oks, E.; Nikolaev, A.; Ezdesir, A.; Tihminlioglu, F.; Tek, Z.; Cetiner, S.; Muntele, C.
Chemical surface characterization of C + H hybrid ion implanted UHMWPE samples were carried out using DSC (differential scanning calorimeter) and TGA (thermal gravimetric analysis) techniques. Samples were implanted with a fluence of 10(17) ion/cm(2) and an extraction voltage of 30 kV. The study of TGA and DSC curves showed that: (1) Polymeric decomposition temperature increased, (2) T-m, Delta C-p and Delta H-m values changed while Delta C-p and Delta H-m increased. T-g value could not be measured, because of some experimental limitations. However, the increase in Delta H-m values showed that T-g values increased, (3) the branch density which indicated the increase in number of cross-link (M-c) decreased in ion implanted samples and (4) increase in Delta H-m values indicated increase in crystallinity of implanted surface of UHMWPE samples. Published by Elsevier B.V.
Structural and Thermal Characterization of Ti plus O Ion Implanted UltraHigh Molecular Weight Polyethylene (UHMWPE)
(Amer Inst Physics, 2009) Oztarhan, A.; Urkac, E. Sokullu; Tihminlioglu, F.; Kaya, N.; Ila, D.; Budak, S.; Chhay, B.; Muntele, C.; Oks, E.; Nikolaev, A.; McDaniel, FD; Doyle, BL
In this work, Metal-Gas Hybrid Ion Implantation technique was used as a tool for the surface modification of Ultra High Molecular Weight Polyethylene (UHMWPE). Samples were Ti + O ion implanted by using Metal-Vapour Vacuum Arc (MEVVA) ion implanter to a fluence of 5x10(16) ion/cm(2) for each species and extraction voltage of 30 kV. Untreated and surface treated samples were investigated by Rutherford Back Scattering (RBS) Spectrometry, Attenuated Total Reflectance - Fourier Transform Infrared (ATR-FTIR) Spectroscopy, Thermo Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). Results indicate that Ti + O ion implantation can be applied on UHMWPE surfaces successfully. ATR-FTIR spectra indicate that the C-H concentration on the surface decreased after Ti + O implantation. Thermal characterization with TGA and DSC shows that polymeric decomposition temperature is shifted after ion implantation.
Thermal Behaviour of W plus C Ion Implanted Ultra High Molecular Weight Polyethylene (UHMWPE)
(Amer Inst Physics, 2009) Urkac, E. Sokullu; Oztarhan, A.; Tihminlioglu, F.; Ila, D.; Budak, S.; Chhay, B.; Muntele, C.; Oks, E.; Nikolaev, A.; McDaniel, FD; Doyle, BL
The aim of this work was to examine thermal behavior of the surface modified Ultra High Molecular Weight Poly Ethylene (UHMWPE) in order to understand the effect of ion implantation on the properties of this polymer which is widely used especially for biomedical applications. UHMWPE samples were Tungsten and Carbon (W+C) hybrid ion implanted by using Metal Vapour Vacuum Arc (MEVVA) ion implantation technique with a fluence of 10 17 ions/cm2 and extraction voltage of 30kV. Untreated and surface-treated samples were investigated by Rutherford Back Scattering (RBS) Analysis, Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) Spectrometry, Thermo Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). This study has shown that ion implantation represents a powerful tool on modifying thermal properties of UHMWPE surfaces. This combination of properties can make implanted UHMWPE a preferred material for biomedical applications.
Thermal characterization of Ag and Ag plus N ion implanted ultra-high molecular weight polyethylene (UHMWPE)
(Elsevier Science Bv, 2007) Urkac, E. Sokullu; Oztarhan, A.; Tihminlioglu, F.; Kaya, N.; Ila, D.; Muntele, C.; Budak, S.; Oks, E.; Nikolaev, A.; Ezdesir, A.; Tek, Z.
Most of total hip joints are composed of ultra-high molecular weight polyethylene (UHMWPE). However, as ultra-high molecular weight polyethylene is too stable in a body, wear debris may accumulate and cause biological response such as bone absorption and loosening of prosthesis. In this study, ultra-high molecular weight polyethylene samples were Ag and Ag + N hybrid ion implanted by using MEVVA ion implantation technique to improve its surface properties. Samples were implanted with a fluence of 10(17) ion/cm(2) and extraction voltage of 30 kV. Implanted and unimplanted samples were investigated by thermo-gravimetry analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), optical microscopy (OM) and contact Angle measurement. Thermal characterization results showed that the ion bombardment induced an increase in the % crystallinity, onset and termination degradation temperatures of UHMWPE. (c) 2007 Elsevier B.V. All rights reserved.

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