The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Lin Sicong - One of the best experts on this subject based on the ideXlab platform.
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blood compatibility of Polyurethane Surface grafted copolymerization with sulfobetaine monomer
Colloids and Surfaces B: Biointerfaces, 2004Co-Authors: Yuan Jiang, Bian Rongbing, Shen Jian, Tong Ling, Lin SicongAbstract:Abstract Surface modification is an effective way to improve the hemocompatibility and remain bulk properties of biomaterials. Recently, polymer tailed with zwitterions was found having good blood compatibility. In this study, the grafting copolymerization of sulfobetaine onto Polyurethane Surface was obtained through two steps. In the first step, Polyurethane film coupled with vinyl groups was obtained through the reaction between the carboxyl group of acrylic acid (AA) and the NH-urethane group of Polyurethane by dicyclohexylcarbodiimide (DCC). In the second step, sulfobetaine was grafted copolymerization on the Surface using AIBN as an initiator. The reaction process was monitored with ATR-IR spectra and X-ray photoelectron spectroscopy (XPS) spectra. The wettability of films was investigated by water contact angle measurement. The blood compatibility of the grafted films was evaluated by platelet adhesion in platelet rich plasma (PRP) and protein absorption in bovine fibrinogen (BFG). Low platelet adhesion was observed on the grafted films incubated in PRP for 1 and 3 h, respectively. The protein absorption was reduced on the grafted films after incubated in bovine fibrinogen for 2 h. All of these results revealed that the improved blood compatibility was obtained by grafting copolymerization with zwitterionic monomer of sulfobetaine onto Polyurethane film. In addition, introducing vinyl groups onto Surface through DCC and AA is a novel method to functionalize Polyurethane for further modification.
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Platelet adhesive resistance of Polyurethane Surface grafted with zwitterions of sulfobetaine.
Colloids and surfaces. B Biointerfaces, 2004Co-Authors: Yuan Jiang, Shen Jian, Hou Qing-feng, Liu Baolei, Lin SicongAbstract:A possible approach to improve the blood compatibility of poly(etherurethane)s (PU) involves the covalent attachment of key molecular on its Surface. Recently, polymer tailed with zwitterions was found having good blood compatibility. The purpose of present study was to design and synthesis a novel nonthrombogenic biomaterial by modifying the Surface of poly(etherurethane) with zwitterions of sulfobetaine via HDI spacer. The films of Polyurethane were grafted with sulfobetaine by a three-step procedure. In the first step, the film Surfaces were treated with hexamethylene diisocyanate (HDI) in toluene at 50 degrees C in the presence of di-n-butyl tin dilaurate(DBTDL) as a catalyst. The extent of the reaction was measured by ATR-IR spectra; a maximum number of free NCO group was obtained after a reaction time of 2.5 h. In the second step, the primary amine group of N,N-diethylethylenediamine (DEA) or N,N-dimethylethylenediamine (DMA) was allowed to react in toluene with isocyanate groups bound on Surface. In the third step, two kinds of sulfobetaines were formed in the Surface through the ring-opening reaction between tertiary amine of DMA or DEA and 1,3- propanesultone (PS). The reaction process was monitored with ATR-IR spectra and XPS spectra. The wettability of films was investigated by water contact angle measurement. A platelet adhesion experiment was conducted as a preliminary test to confirm the improved blood compatibility of PU. The number of platelets adhering to PU decreased greatly compared to original after 1 h and 3 h of contact with human plate-rich plasma.
Yuan Jiang - One of the best experts on this subject based on the ideXlab platform.
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blood compatibility of Polyurethane Surface grafted copolymerization with sulfobetaine monomer
Colloids and Surfaces B: Biointerfaces, 2004Co-Authors: Yuan Jiang, Bian Rongbing, Shen Jian, Tong Ling, Lin SicongAbstract:Abstract Surface modification is an effective way to improve the hemocompatibility and remain bulk properties of biomaterials. Recently, polymer tailed with zwitterions was found having good blood compatibility. In this study, the grafting copolymerization of sulfobetaine onto Polyurethane Surface was obtained through two steps. In the first step, Polyurethane film coupled with vinyl groups was obtained through the reaction between the carboxyl group of acrylic acid (AA) and the NH-urethane group of Polyurethane by dicyclohexylcarbodiimide (DCC). In the second step, sulfobetaine was grafted copolymerization on the Surface using AIBN as an initiator. The reaction process was monitored with ATR-IR spectra and X-ray photoelectron spectroscopy (XPS) spectra. The wettability of films was investigated by water contact angle measurement. The blood compatibility of the grafted films was evaluated by platelet adhesion in platelet rich plasma (PRP) and protein absorption in bovine fibrinogen (BFG). Low platelet adhesion was observed on the grafted films incubated in PRP for 1 and 3 h, respectively. The protein absorption was reduced on the grafted films after incubated in bovine fibrinogen for 2 h. All of these results revealed that the improved blood compatibility was obtained by grafting copolymerization with zwitterionic monomer of sulfobetaine onto Polyurethane film. In addition, introducing vinyl groups onto Surface through DCC and AA is a novel method to functionalize Polyurethane for further modification.
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Platelet adhesive resistance of Polyurethane Surface grafted with zwitterions of sulfobetaine.
Colloids and surfaces. B Biointerfaces, 2004Co-Authors: Yuan Jiang, Shen Jian, Hou Qing-feng, Liu Baolei, Lin SicongAbstract:A possible approach to improve the blood compatibility of poly(etherurethane)s (PU) involves the covalent attachment of key molecular on its Surface. Recently, polymer tailed with zwitterions was found having good blood compatibility. The purpose of present study was to design and synthesis a novel nonthrombogenic biomaterial by modifying the Surface of poly(etherurethane) with zwitterions of sulfobetaine via HDI spacer. The films of Polyurethane were grafted with sulfobetaine by a three-step procedure. In the first step, the film Surfaces were treated with hexamethylene diisocyanate (HDI) in toluene at 50 degrees C in the presence of di-n-butyl tin dilaurate(DBTDL) as a catalyst. The extent of the reaction was measured by ATR-IR spectra; a maximum number of free NCO group was obtained after a reaction time of 2.5 h. In the second step, the primary amine group of N,N-diethylethylenediamine (DEA) or N,N-dimethylethylenediamine (DMA) was allowed to react in toluene with isocyanate groups bound on Surface. In the third step, two kinds of sulfobetaines were formed in the Surface through the ring-opening reaction between tertiary amine of DMA or DEA and 1,3- propanesultone (PS). The reaction process was monitored with ATR-IR spectra and XPS spectra. The wettability of films was investigated by water contact angle measurement. A platelet adhesion experiment was conducted as a preliminary test to confirm the improved blood compatibility of PU. The number of platelets adhering to PU decreased greatly compared to original after 1 h and 3 h of contact with human plate-rich plasma.
Jawahar L Mehta - One of the best experts on this subject based on the ideXlab platform.
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Structural evaluation of radially expandable cardiovascular stents encased in a Polyurethane film.
Journal of Biomedical Materials Research Part B, 2006Co-Authors: Steve Trigwell, Samiran De, R Sharma, Malay K. Mazumder, Jawahar L MehtaAbstract:A method of encasing cardiovascular stents with an expandable Polyurethane coating has been developed to provide a smooth homogeneous inner wall allowing for a confluent growth of endothelial cells. In this design, the metal wire stent structure is completely covered by the Polyurethane film, minimizing biocorrosion of the metal (stainless steel or nitinol), and providing a homogeneous Surface for Surface treatment and incorporation of various eluting drugs to prevent platelet aggregation while supporting endothelialization. The Polyurethane Surface was treated with a helium plasma for sterilization and promotes growth of cells. The article details the performance of the coated film to expand with the metal stent up to 225% during deployment. Stress/strain behavior of Polyurethane films, subsequent plasma treatment of the Surface, and the adhesion of the coating to the stent structure upon expansion are presented. A film of less than 25 μm was found to be sufficient for corrosion resistance and flexibility without producing any excess stress on the stent structure. Straining the film to 225% and plasma modification did not affect the mechanical and Surface properties, but allowed for improved biocompatibility as determined by the critical Surface tension, Surface chemistry, and roughness. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Shen Jian - One of the best experts on this subject based on the ideXlab platform.
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blood compatibility of Polyurethane Surface grafted copolymerization with sulfobetaine monomer
Colloids and Surfaces B: Biointerfaces, 2004Co-Authors: Yuan Jiang, Bian Rongbing, Shen Jian, Tong Ling, Lin SicongAbstract:Abstract Surface modification is an effective way to improve the hemocompatibility and remain bulk properties of biomaterials. Recently, polymer tailed with zwitterions was found having good blood compatibility. In this study, the grafting copolymerization of sulfobetaine onto Polyurethane Surface was obtained through two steps. In the first step, Polyurethane film coupled with vinyl groups was obtained through the reaction between the carboxyl group of acrylic acid (AA) and the NH-urethane group of Polyurethane by dicyclohexylcarbodiimide (DCC). In the second step, sulfobetaine was grafted copolymerization on the Surface using AIBN as an initiator. The reaction process was monitored with ATR-IR spectra and X-ray photoelectron spectroscopy (XPS) spectra. The wettability of films was investigated by water contact angle measurement. The blood compatibility of the grafted films was evaluated by platelet adhesion in platelet rich plasma (PRP) and protein absorption in bovine fibrinogen (BFG). Low platelet adhesion was observed on the grafted films incubated in PRP for 1 and 3 h, respectively. The protein absorption was reduced on the grafted films after incubated in bovine fibrinogen for 2 h. All of these results revealed that the improved blood compatibility was obtained by grafting copolymerization with zwitterionic monomer of sulfobetaine onto Polyurethane film. In addition, introducing vinyl groups onto Surface through DCC and AA is a novel method to functionalize Polyurethane for further modification.
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Platelet adhesive resistance of Polyurethane Surface grafted with zwitterions of sulfobetaine.
Colloids and surfaces. B Biointerfaces, 2004Co-Authors: Yuan Jiang, Shen Jian, Hou Qing-feng, Liu Baolei, Lin SicongAbstract:A possible approach to improve the blood compatibility of poly(etherurethane)s (PU) involves the covalent attachment of key molecular on its Surface. Recently, polymer tailed with zwitterions was found having good blood compatibility. The purpose of present study was to design and synthesis a novel nonthrombogenic biomaterial by modifying the Surface of poly(etherurethane) with zwitterions of sulfobetaine via HDI spacer. The films of Polyurethane were grafted with sulfobetaine by a three-step procedure. In the first step, the film Surfaces were treated with hexamethylene diisocyanate (HDI) in toluene at 50 degrees C in the presence of di-n-butyl tin dilaurate(DBTDL) as a catalyst. The extent of the reaction was measured by ATR-IR spectra; a maximum number of free NCO group was obtained after a reaction time of 2.5 h. In the second step, the primary amine group of N,N-diethylethylenediamine (DEA) or N,N-dimethylethylenediamine (DMA) was allowed to react in toluene with isocyanate groups bound on Surface. In the third step, two kinds of sulfobetaines were formed in the Surface through the ring-opening reaction between tertiary amine of DMA or DEA and 1,3- propanesultone (PS). The reaction process was monitored with ATR-IR spectra and XPS spectra. The wettability of films was investigated by water contact angle measurement. A platelet adhesion experiment was conducted as a preliminary test to confirm the improved blood compatibility of PU. The number of platelets adhering to PU decreased greatly compared to original after 1 h and 3 h of contact with human plate-rich plasma.
Jian Shen - One of the best experts on this subject based on the ideXlab platform.
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chemically induced graft copolymerization of 2 hydroxyethyl methacrylate onto Polyurethane Surface for improving blood compatibility
Applied Surface Science, 2011Co-Authors: Chunli He, Xiaobo Huang, Li Li, Miao Wang, Jian Shen, Jiang YuanAbstract:Abstract To improve hydrophilicity and blood compatibility properties of Polyurethane (PU) film, we chemically induced graft copolymerization of 2-hydroxyethyl methacrylate (HEMA) onto the Surface of Polyurethane film using benzoyl peroxide as an initiator. The effects of grafting temperature, grafting time, monomer and initiator concentrations on the grafting yields were studied. The maximum grafting yield value was obtained 0.0275 g/cm2 for HEMA. Characterization of the films was carried out by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), water contact angle measurements. ATR-FTIR data showed that HEMA was successfully grafted onto the PU films Surface. Water contact angle measurement demonstrated the grafted films possessed a relatively hydrophilic Surface. The blood compatibility of the grafted films was preliminarily evaluated by a platelet-rich plasma adhesion test and hemolysis test. The results of platelet adhesion experiment showed that Polyurethane grafted polymerization with monomer of 2-hydroxyethyl methacrylate had good blood compatibility featured by the low platelet adhesion. Hemolysis rate of the PU-g-PHEMA films was dramatically decreased than the ungrafted PU films. This kind of new biomaterials grafted with HEMA monomers might have a potential usage for biomedical applications.
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enhanced blood compatibility of Polyurethane functionalized with sulfobetaine
Colloids and Surfaces B: Biointerfaces, 2008Co-Authors: Jiang Yuan, Jian ShenAbstract:Abstract The purpose of this work is to develop a biocompatible Polyurethane Surface by the tailoring of sulfobetaine. The Polyurethane film was first grafted polymerization with acrylic acid by ozonization, followed by immobilizing sulfobetaine via two routes: (i) synthesize primary amine group terminated sulfobetaine and then couple onto the Surface of Polyurethane using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC); (ii) couple the primary amine group terminated tertiary amine onto the Surface of Polyurethane primarily using EDC and then form sulfobetaine through a ring-opening reaction between tertiary amine and 1,3-propanesultone (PS). The reaction process was monitored with attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The blood compatibility was evaluated by a hemolytic test and platelet-rich plasma (PRP) adhesion experiment. Little hemolysis took place on the Surface of Polyurethane grafted with sulfobetaine. Platelets adhering on the Surface of grafted Polyurethane decreased greatly as compared to the original after 1 and 3 h of incubation with PRP.