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Öğe Aliphatic Polyurethane Films Based on Hexamethylene Diisocyanate and Saccharides for Biocompatible Transparent Coating on Optic Medical Devices(Wiley-V C H Verlag Gmbh, 2022) Gurses, Canbolat; Karaaslan-Tunc, Merve Goksin; Kelestemur, Unzile; Balcioglu, Sevgi; Gulgen, Selam; Koytepe, Suleyman; Ates, BurhanPolyurethanes are widely used in daily life, from the textile industry to medical applications. In this study, a biocompatible and transparent coating from polyethylene glycol-based polyurethanes including different type of saccharide (xylose as monosaccharide, sucrose as disaccharide, or starch as polysaccharide) is prepared. Prepared optically transparent polyurethanes are characterized with different instrumental analysis techniques and contact-angle measurements. Thermogravimetric analysis data allow understanding that the synthesized saccharide based polyurethanes are resistant to high temperatures, which means that medical devices can be easily coated with one of the saccharide-based polymers during the manufacturing process. The study results also show that synthesized polyurethane samples having a different kind of saccharides present high biocompatibility and transparency properties via In vitro cytotoxicity analysis and optic transparency tests. For xylose, sucrose, or starch containing polyurethanes, the tranmittance values are 97.72%, 85.20%, and 89.23%, respectively. In addition, scanning electron microscope images show that the samples also have smooth surfaces which can be used for proper coating of medical devices. Consequently, this manuscript addresses synthesis and characterization of the optically transparent polyurethanes based on specific saccharides for biocompatible and transparent surfaces especially in optic medical devices such as colonoscopy applications and laparoscopic detection probes.Öğe Biodegradable non-aromatic adhesive polyurethanes based on disaccharides for medical applications(Elsevier Sci Ltd, 2014) Ates, Burhan; Koytepe, Suleyman; Karaaslan, Merve Goksin; Balcioglu, Sevgi; Gulgen, SelamThis work addresses synthesis, characterization, adhesive properties, protein adsorption and in vitro biodegradation of non-aromatic polyurethanes (NPUs). The following reactants were used in the syntheses of polyurethanes (PUs): non-aromatic 4,4'-Methylenebis(cyclohexyl isocyanate) (MCI), disaccharides (maltose and sucrose) and polyethylene glycol 200 (PEG 200). The NPUs exhibited low glass transition temperature (T-g) and good thermal stability. The dynamic contact angles on NPUs were influenced by the ratios of PEG 200-disaccharide monomer and the hard segment of the NPUs. The highest adhesion strength in whole polyurethanes was found as 307.6 +/- 50.1 kPa for 15% sucrose containing polyurethane. Protein adsorptions of polyurethane films were measured as average 10 pg Bovine Serum Albumin (BSA)/cm(2) and 5 mu g fibrinogen/cm(2) for maltose, and 15 mu g BSA/cm(2) and 5 mu g fibrinogen/cm(2) for sucrose. Biodegradability ratios of NPUs were in the range of 15-35% for 8 weeks depending on the disaccharides containing NPUs. (C) 2013 Elsevier Ltd. All rights reserved.Öğe Biomimetic approach to tunable adhesion of polyurethane adhesives through Fe3+ crosslinking and hydrophobic tween units with balance of adhesion/cohesion forces(Elsevier Sci Ltd, 2019) Ates, Burhan; Koytepe, Suleyman; Balcioglu, Sevgi; Karaaslan, Merve Goksin; Kelestemur, Unzile; Gulgen, Selam; Ozhan, OnuralBiocompatible adhesives have some limitations such as weak adhesion and low flexibility. To overcome these limitations, we described multiple strategies to provide strong adhesion and high flexibility through Tweens, chlorogenic acid (CLA) and polyethylene glycol (PEG) by reducing excessive interaction between tissue and the adhesive. We synthesized polyurethane-based adhesives using aliphatic 4,4'-methylenebis(cyclohexyl isocyanate) (HMDI), PEG, CLA and Tween units. Hydrophobic side chains in polymer resulted in lower Tg (- 36.95-30.36 degrees C) which indicated more flexibility. The highest adhesion strengths were found as almost 346 kPa for bare polyurethane and 492 kPa for chelated polymer (PU-T40-CLA-15% (5% Tween 40, 15% chlorogenic acid and 80% PEG 200 containing polymer)) with FeCl3. The addition of Tween units provided more stable structure to polymers which proved with in vitro erosion studies. Relatively low erosion values were seen as 5.7, 5.6 and 8.2% in PU-T40-CLA-5% (15% Tween 40, 5% chlorogenic acid and 80% PEG 200 containing polymer), PU-T40-CLA-10% (10% Tween 40, 10% chlorogenic acid and 80% PEG 200 containing polymer), and PU-T40-CLA-15% (5% Tween 40, 15% chlorogenic acid and 80% PEG 200 containing polymer), respectively. In vitro biocompatibility results showed high cell viability in PU-T40-15% as more than 100%. Overall, our findings indicated that these material designs (PU-T-CLAs) provided to overcome the significant challenges of tissue adhesives by improving the flexible character and adhesive strength of the adhesives.Öğe Chlorogenic Acid Containing Bioinspired Polyurethanes: Biodegradable Medical Adhesive Materials(Taylor & Francis As, 2015) Ates, Burhan; Koytepe, Suleyman; Karaaslan, Merve Goksin; Balcioglu, Sevgi; Gulgen, Selam; Demirbilek, Murat; Denkbas, Emir BakiHighly adhesive bioinspired polyurethanes (PUs) based on the chlorogenic acid (CLA) were prepared from 4,4'-methylenebis (cyclohexyl isocyanate) (MCI) and polyethylene glycol 200 (PEG 200). The polyurethanes exhibited the lowest glass transition temperature (T-g), improved thermal stability and good adhesive properties. The highest adhesion strength was found as 373.3 +/- 47.5 kPa for 10% CLA containing PUs. The polyurethanes were observed to be biodegradable and were in the range of 19-24% for 8 weeks as depending on chlorogenic acid containing of PUs. As a result, prepared biocompatible-adhesive bioinspired polyurethanes are good candidates for medical applications as a tissue adhesive material. [GRAPHICS] .Öğe Design of Xylose-Based Semisynthetic Polyurethane Tissue Adhesives with Enhanced Bioactivity Properties(Amer Chemical Soc, 2016) Balcioglu, Sevgi; Parlakpinar, Hakan; Vardi, Nigar; Denkbas, Emir Baki; Karaaslan, Merve Goksin; Gulgen, Selam; Taslidere, ElifDeveloping biocompatible tissue adhesives with high adhesion properties is a highly desired goal of the tissue engineering due to adverse effects of the sutures. Therefore, our work involves synthesis, characterization, adhesion properties, protein adsorption, in vitro biodegradation, in vitro and in vivo biocompatibility properties of xylose-based semisynthetic polyurethane (NPU-PEG-X) bioadhesives. Xylose-based semisynthetic polyurethanes were developed by the reaction among 4,4'-methylenebis(cyclohexyl isocyanate) (MCI), xylose and polyethylene glycol 200 (PEG). Synthesized polyurethanes (PUs) showed good thermal stability and high adhesion strength. The highest values in adhesion strength were measured as 415.0 +/- 48.8 and 94.0 +/- 2.8 kPa for aluminum substrate and muscle tissue in 15% xylose containing PUs (NPU-PEG-X-15%), respectively. The biodegradation of NPU-PEG-X-15% was also determined as 19.96 +/- 1.04% after 8 weeks of incubation. Relative cell viability of xylose containing PU was above 86%. Moreover, 10% xylose containing NPU-PEG-X (NPU-PEG-X-10%) sample has favorable tissue response, and inflammatory reaction between 1 and 6 weeks implantation period. With high adhesiveness and biocompatibility properties, NPU-PEG-X can be used in the medical field as supporting materials for preventing the fluid leakage after abdominal surgery or wound closure.