Biocompatibility,particularly blood compatibility is the most important property required for biomedical materials.The improvement of blood compatibility is always an important research task for biomaterial research a...Biocompatibility,particularly blood compatibility is the most important property required for biomedical materials.The improvement of blood compatibility is always an important research task for biomaterial research and development.It is an important way to develop biomaterials by constructing special molecules onto the proper mechanical material surface.Polyetherurethanes are widely used as biomaterials due to their good biocompatibility and mechanical properties.Nevertheless,their blood compatibility is still not adequate for the more demanding applications.The purpose of present study was to synthesis a novel nonthrombogenic biomaterial by modifying the surface of polyetherurethane.Ozone was used to introduce active peroxide groups onto polyetherurethane surface and graft polymerization of N,N dimethyl N methacryloxyethyl N (3 sulfopropyl) ammonium (DMMSA), a sulfobetaine structure,onto the ozone activated polyetherurethane surface was conducted.The nonthrombogenic properties of grafted film were also studied.The grafted film was characterized by ATR FTIR,XPS and contact angle measurement.The ATR FTIR,XPS of the grafted PU film indicated that the graft polymerization did take place,the grafted PU film surface was covered with the DMMSA polymer.The grafting yields in different condition were studied.The grafting yields increased with the increase of the monomer concentration.Water absorption and contact angle showed that the hydrophilicity of the film had been improved greatly,and the hydrophilicity of the film increased with the grafting yield.The blood compatibility of the grafted films was evaluated by platelet adhesion in platelet rich plasma and scanning electron microscopy observation using PU film as the reference.No platelet adhesion was observed for the grafted films incubated for 60 min and 180 min,however,the ungrafted PU film was covered with platelet.The result of platelet adhesion experiment indicated that the PDMMSA chains could prevent platelet adhesion.That means this new material is expected to have potential biomedical applications.展开更多
With the aim of creating biodegradable materials for medical devices clinical appointments with high hemocompatibility we have developed a new polymer product.The basis of this product is plasticized by polyethylene g...With the aim of creating biodegradable materials for medical devices clinical appointments with high hemocompatibility we have developed a new polymer product.The basis of this product is plasticized by polyethylene glycol bacterial copolymer of hydroxybutyrate and oxovalerate. A well-known antitbrombotic supplement--acetylsalicylic acid has been added to improve hemocompatibility in the polymer. The results of our studies showed a controlled prolonged separation of acetylsalicylic acid from polymeric material in the blood. We studied in vitro the dynamics of liberation of acetylsalicylic acid from polymeric coatings. It was shown that the concentration of polyethylene glycol and the thickness of the polymer layer can affect the rate of diffusion of acetylsalicylic acid from polymer films.展开更多
The objective of this study was to investigate the hemocompatibility and cell responses to some novel poly（L-lactide） （PLA） composites containing surface modified hydroxyapatite particles for potential application...The objective of this study was to investigate the hemocompatibility and cell responses to some novel poly（L-lactide） （PLA） composites containing surface modified hydroxyapatite particles for potential applications as a bone substitute material. The surface of hydroxyapatite （HA） particles was first grafted with L-lactic acid oligomers to form grafted HA （g-HA） particles. The g-HA particles were further blended with PLA to prepare g-HA/PLA composites. Our previous study has shown signifi- cant improvement in tensile properties of these materials due to the enhanced interracial adhesion between the polymer matrix and HA particles. To further investigate the potential applications of these composites in bone repair and other orthopedic sur- geries, a series of in vitro and in vivo experiments were conducted to examine the cell responses and hemocompatibility of the materials. In vitro experiments showed that the g-HA/PLA composites were well tolerated by the L-929 cells. Hemolysis of the composites was lower than that of pure PLA. Subcutaneous implantation demonstrated that the g-HA/PLA composites were more favorable than the control materials for soft tissue responses. The results suggested that the g-HA/PLA composites are promising and safe materials with potential applications in tissue engineering.展开更多
Currently commercialized coronary stents are mainly made of the medical 316L stainless steel and cobalt-based alloy(L605) due to their good combination of properties,especially excellent mechanical properties.However,...Currently commercialized coronary stents are mainly made of the medical 316L stainless steel and cobalt-based alloy(L605) due to their good combination of properties,especially excellent mechanical properties.However,the presence of high quantity of nickel and/or cobalt elements,the agents known to trigger the toxic and allergic responses,in these materials has caused many clinic concerns.The potential adverse effect of nickel ions release has prompted the development of high nitrogen nickel-free austenitic stainless steels for medical application.Nitrogen in steel is not only to replace the nickel but also improve the properties of steel.In this paper,the harmfulness and release of nickel from metallic stents,and the advantages in mechanical properties and hemocompatibility of high nitrogen nickel-free stainless steels for coronary stents are reviewed.Apart from the highlight of nickel-free,the superiority of high strength and better hemocompatibility of high nitrogen nickel-free stainless steels can guarantee to manufacture thinner strut coronary stents with remarkable anticoagulation ability.High nitrogen nickel-free stainless steels as a promising coronary stents material will attract more and more clinical doctors and stents makers to bring them into clinical application.展开更多
文摘Biocompatibility,particularly blood compatibility is the most important property required for biomedical materials.The improvement of blood compatibility is always an important research task for biomaterial research and development.It is an important way to develop biomaterials by constructing special molecules onto the proper mechanical material surface.Polyetherurethanes are widely used as biomaterials due to their good biocompatibility and mechanical properties.Nevertheless,their blood compatibility is still not adequate for the more demanding applications.The purpose of present study was to synthesis a novel nonthrombogenic biomaterial by modifying the surface of polyetherurethane.Ozone was used to introduce active peroxide groups onto polyetherurethane surface and graft polymerization of N,N dimethyl N methacryloxyethyl N (3 sulfopropyl) ammonium (DMMSA), a sulfobetaine structure,onto the ozone activated polyetherurethane surface was conducted.The nonthrombogenic properties of grafted film were also studied.The grafted film was characterized by ATR FTIR,XPS and contact angle measurement.The ATR FTIR,XPS of the grafted PU film indicated that the graft polymerization did take place,the grafted PU film surface was covered with the DMMSA polymer.The grafting yields in different condition were studied.The grafting yields increased with the increase of the monomer concentration.Water absorption and contact angle showed that the hydrophilicity of the film had been improved greatly,and the hydrophilicity of the film increased with the grafting yield.The blood compatibility of the grafted films was evaluated by platelet adhesion in platelet rich plasma and scanning electron microscopy observation using PU film as the reference.No platelet adhesion was observed for the grafted films incubated for 60 min and 180 min,however,the ungrafted PU film was covered with platelet.The result of platelet adhesion experiment indicated that the PDMMSA chains could prevent platelet adhesion.That means this new material is expected to have potential biomedical applications.
文摘With the aim of creating biodegradable materials for medical devices clinical appointments with high hemocompatibility we have developed a new polymer product.The basis of this product is plasticized by polyethylene glycol bacterial copolymer of hydroxybutyrate and oxovalerate. A well-known antitbrombotic supplement--acetylsalicylic acid has been added to improve hemocompatibility in the polymer. The results of our studies showed a controlled prolonged separation of acetylsalicylic acid from polymeric material in the blood. We studied in vitro the dynamics of liberation of acetylsalicylic acid from polymeric coatings. It was shown that the concentration of polyethylene glycol and the thickness of the polymer layer can affect the rate of diffusion of acetylsalicylic acid from polymer films.
基金supported by the Research Fund for the Doctoral Program of Higher Education(Grant No.20060217012)
文摘The objective of this study was to investigate the hemocompatibility and cell responses to some novel poly（L-lactide） （PLA） composites containing surface modified hydroxyapatite particles for potential applications as a bone substitute material. The surface of hydroxyapatite （HA） particles was first grafted with L-lactic acid oligomers to form grafted HA （g-HA） particles. The g-HA particles were further blended with PLA to prepare g-HA/PLA composites. Our previous study has shown signifi- cant improvement in tensile properties of these materials due to the enhanced interracial adhesion between the polymer matrix and HA particles. To further investigate the potential applications of these composites in bone repair and other orthopedic sur- geries, a series of in vitro and in vivo experiments were conducted to examine the cell responses and hemocompatibility of the materials. In vitro experiments showed that the g-HA/PLA composites were well tolerated by the L-929 cells. Hemolysis of the composites was lower than that of pure PLA. Subcutaneous implantation demonstrated that the g-HA/PLA composites were more favorable than the control materials for soft tissue responses. The results suggested that the g-HA/PLA composites are promising and safe materials with potential applications in tissue engineering.
基金supported by the National Natural Science Foundation of China (Grant No. 31000428)the National Basic Research Program of China ("973" Program) (Grant No. 2012CB619101)
文摘Currently commercialized coronary stents are mainly made of the medical 316L stainless steel and cobalt-based alloy(L605) due to their good combination of properties,especially excellent mechanical properties.However,the presence of high quantity of nickel and/or cobalt elements,the agents known to trigger the toxic and allergic responses,in these materials has caused many clinic concerns.The potential adverse effect of nickel ions release has prompted the development of high nitrogen nickel-free austenitic stainless steels for medical application.Nitrogen in steel is not only to replace the nickel but also improve the properties of steel.In this paper,the harmfulness and release of nickel from metallic stents,and the advantages in mechanical properties and hemocompatibility of high nitrogen nickel-free stainless steels for coronary stents are reviewed.Apart from the highlight of nickel-free,the superiority of high strength and better hemocompatibility of high nitrogen nickel-free stainless steels can guarantee to manufacture thinner strut coronary stents with remarkable anticoagulation ability.High nitrogen nickel-free stainless steels as a promising coronary stents material will attract more and more clinical doctors and stents makers to bring them into clinical application.
