Poly (ethyleneglycol monomethylether) methacrylate (PEGMM)was synthesized by means of the reaction of methacrylyl chloride with sodium monomethylpolyethyleneglycoxide and was characterized by FTIR,;H-NMR,and ultra...Poly (ethyleneglycol monomethylether) methacrylate (PEGMM)was synthesized by means of the reaction of methacrylyl chloride with sodium monomethylpolyethyleneglycoxide and was characterized by FTIR,;H-NMR,and ultraviolet spectrometries. A series of poly (vinyl alcohol)-graft-PEGMM (PVA-g-PEGMM )and methyl methacrylate-PEGMM copolymer (PMMA-PEGMM) were prepared and tested for antithrombogenicity in vitro. The results indicate that the antithrombogenicity of the copolymers basically increases with the increasing of the DP of polyoxyethylene (POE) chain and tends to a plateau after the DP around 114,i.e. the long chain structure of POE is favourable to the antithrombogenicityof its copolymers ;moreover, the extent of the improvement ofantithrombogenicity also relates to the PEGMM content of the copolymers and the kind of the matrix that the POE chains are located on. These results are consistent with the anticipation of the hypothesis of maintaining proteins normal conformations for blood compatible bioraaterials.展开更多
A novel class of segmented copolymers, dimethyldiphenylpolysiloxane/poly (oxytetramethylene)-polyurea (PSPEU), was synthesized from α , ω-bis (γ-aminopropyl) dimethyldiphenylpolysiloxane (APMPS), which was prepared...A novel class of segmented copolymers, dimethyldiphenylpolysiloxane/poly (oxytetramethylene)-polyurea (PSPEU), was synthesized from α , ω-bis (γ-aminopropyl) dimethyldiphenylpolysiloxane (APMPS), which was prepared by means of basic ring-opening copolymerization of octamethylcyclotetrasiloxane, hexaphenylcyclotrisiloxane and 1, 3-bis (γ-aminopropyl) tetramethyl disiloxane. The relationships between the diphenylsiloxy contents and the properties of APMPS, including refractive index, glass transition temperature, solubility parameter as well as thermal stability, were investigated; meanwhile, the thermal stability, dynamic mechanical properties, mechanical properiesas well as the antithrombogenicity in vitro of the PSPEU were also revealed.展开更多
A novel class of aromatic polyimide-silicone segmented copolymer was synthesized with α, ω-bis (γ-aminopropyl) polydimethyldiphenylsiloxane (APMPS) as a silicone segment precursor, from which the segmented polyamic...A novel class of aromatic polyimide-silicone segmented copolymer was synthesized with α, ω-bis (γ-aminopropyl) polydimethyldiphenylsiloxane (APMPS) as a silicone segment precursor, from which the segmented polyamic acid-b-silicone intermediate could be prepared simply with DMF as solvent. The segmented copolymer displays microphase separation and exhibits improved antithrombogenicity, which depends mainly upon both the content level and the DP of the silicone segment. Thermal stability and mechanical property of the copolymer are between that of the aromatic polyimide and the silicone, and also relate to both the content level and the DP of the silicone segment.展开更多
Immobilization of heparin on biomaterials surface has been proven to be an effective strategy for preventing thrombus formation. However, the procedures of most immobilization methods(physical adsorption, covalent li...Immobilization of heparin on biomaterials surface has been proven to be an effective strategy for preventing thrombus formation. However, the procedures of most immobilization methods(physical adsorption, covalent linkage, electrostatic interaction) are complicated and time-consuming. In the present study, heparin with various concentrations immobilized on a titanium(Ti) substrate via polydopamine layer for improving blood compatibility was investigated. Water contact angle measurement showed that the immobilization of heparin resulted in an increase of the hydrophilicity. X-ray photoelectron spectroscopy(XPS) and Toluidine Blue O(TBO) tests displayed that the heparin molecules were successfully immobilized on Ti surface. The evaluations of blood compatibility(hemolysis rate, APTT, platelet adhesion and activation, fibrinogen conformational change) showed that the immobilization of heparin decreased hemolysis rate, prolonged blood coagulation time, reduced platelets adhesion and activation, and induced less fibrinogen conformational change. Moreover, a significant inhibition of blood coagulation and platelet adhesion was obtained when the heparin concentration was higher than 5 mg/mL, indicating that only with a certain surface densities could heparin perform its anticoagulant properties well. The results suggest that the immobilization of heparin via polydopamine layer can confer excellent antithrombotic properties, and the heparin immobilization method via polydopamine layer provides an alternative approach for other biomolecules immobilization on biomaterials surface. Thus it is envisaged that this method will be potentially useful for the surface modifi cation of blood-contacting biomaterials.展开更多
In this paper, blood compatibility of carbonnitride film synthesized by ion beam enhanced deposition is studied. Clotting time measurement, platelet adhesion test and surface energy determination were performed to eva...In this paper, blood compatibility of carbonnitride film synthesized by ion beam enhanced deposition is studied. Clotting time measurement, platelet adhesion test and surface energy determination were performed to evaluate the interaction between blood and material. The results show that carbonnitride film has better blood compatibility than titanium, and may be promising in biomaterial filed.展开更多
文摘Poly (ethyleneglycol monomethylether) methacrylate (PEGMM)was synthesized by means of the reaction of methacrylyl chloride with sodium monomethylpolyethyleneglycoxide and was characterized by FTIR,;H-NMR,and ultraviolet spectrometries. A series of poly (vinyl alcohol)-graft-PEGMM (PVA-g-PEGMM )and methyl methacrylate-PEGMM copolymer (PMMA-PEGMM) were prepared and tested for antithrombogenicity in vitro. The results indicate that the antithrombogenicity of the copolymers basically increases with the increasing of the DP of polyoxyethylene (POE) chain and tends to a plateau after the DP around 114,i.e. the long chain structure of POE is favourable to the antithrombogenicityof its copolymers ;moreover, the extent of the improvement ofantithrombogenicity also relates to the PEGMM content of the copolymers and the kind of the matrix that the POE chains are located on. These results are consistent with the anticipation of the hypothesis of maintaining proteins normal conformations for blood compatible bioraaterials.
文摘A novel class of segmented copolymers, dimethyldiphenylpolysiloxane/poly (oxytetramethylene)-polyurea (PSPEU), was synthesized from α , ω-bis (γ-aminopropyl) dimethyldiphenylpolysiloxane (APMPS), which was prepared by means of basic ring-opening copolymerization of octamethylcyclotetrasiloxane, hexaphenylcyclotrisiloxane and 1, 3-bis (γ-aminopropyl) tetramethyl disiloxane. The relationships between the diphenylsiloxy contents and the properties of APMPS, including refractive index, glass transition temperature, solubility parameter as well as thermal stability, were investigated; meanwhile, the thermal stability, dynamic mechanical properties, mechanical properiesas well as the antithrombogenicity in vitro of the PSPEU were also revealed.
文摘A novel class of aromatic polyimide-silicone segmented copolymer was synthesized with α, ω-bis (γ-aminopropyl) polydimethyldiphenylsiloxane (APMPS) as a silicone segment precursor, from which the segmented polyamic acid-b-silicone intermediate could be prepared simply with DMF as solvent. The segmented copolymer displays microphase separation and exhibits improved antithrombogenicity, which depends mainly upon both the content level and the DP of the silicone segment. Thermal stability and mechanical property of the copolymer are between that of the aromatic polyimide and the silicone, and also relate to both the content level and the DP of the silicone segment.
基金Funded by the Foundation of Jiangsu Provincial Key Laboratory for Interventional Medical Devices(JR1205)the National Natural Science Foundation of China(Nos.30870629,51175212)+2 种基金the Key Basic Research Program(2011CB606204)the Natural Science Research Program of Jiangsu Education Department(No.13KJB310014)the Natural Science Foundation of Nantong University(No.13R23)
文摘Immobilization of heparin on biomaterials surface has been proven to be an effective strategy for preventing thrombus formation. However, the procedures of most immobilization methods(physical adsorption, covalent linkage, electrostatic interaction) are complicated and time-consuming. In the present study, heparin with various concentrations immobilized on a titanium(Ti) substrate via polydopamine layer for improving blood compatibility was investigated. Water contact angle measurement showed that the immobilization of heparin resulted in an increase of the hydrophilicity. X-ray photoelectron spectroscopy(XPS) and Toluidine Blue O(TBO) tests displayed that the heparin molecules were successfully immobilized on Ti surface. The evaluations of blood compatibility(hemolysis rate, APTT, platelet adhesion and activation, fibrinogen conformational change) showed that the immobilization of heparin decreased hemolysis rate, prolonged blood coagulation time, reduced platelets adhesion and activation, and induced less fibrinogen conformational change. Moreover, a significant inhibition of blood coagulation and platelet adhesion was obtained when the heparin concentration was higher than 5 mg/mL, indicating that only with a certain surface densities could heparin perform its anticoagulant properties well. The results suggest that the immobilization of heparin via polydopamine layer can confer excellent antithrombotic properties, and the heparin immobilization method via polydopamine layer provides an alternative approach for other biomolecules immobilization on biomaterials surface. Thus it is envisaged that this method will be potentially useful for the surface modifi cation of blood-contacting biomaterials.
文摘In this paper, blood compatibility of carbonnitride film synthesized by ion beam enhanced deposition is studied. Clotting time measurement, platelet adhesion test and surface energy determination were performed to evaluate the interaction between blood and material. The results show that carbonnitride film has better blood compatibility than titanium, and may be promising in biomaterial filed.