Biodegradable stents made of magnesium(Mg)and its alloys have been developed to minimize persistent inflammation or in-stent restenosis,which are the main problems for permanent stents.However,their rapid corrosion be...Biodegradable stents made of magnesium(Mg)and its alloys have been developed to minimize persistent inflammation or in-stent restenosis,which are the main problems for permanent stents.However,their rapid corrosion behavior under physiological conditions leads to poor vascular compatibility and premature structural failure,which remains an important unsolved clinical problem.Herein,we demonstrate a new strategy for solving this problem by combining poly(ether imide)(PEI)coating and subsequent tantalum(Ta)ion implantation.The PEI coating covers the whole surface of the Mg stent uniformly via a spray coating technique and provides Mg with superior corrosion resistance and stable sirolimus-carrying ability.Ta ion implantation is conducted by a sputtering-based plasma immersion ion implantation technique only onto the luminal surface of the PEI-coated Mg stent.Its extremely short processing time(<30 s)permits preservation of the PEI coating’s corrosion protection ability and sirolimus loading characteristics.In addition,a Ta-implanted skin layer that forms on the topmost surface of the PEI coating plays an effective role in not only preventing a rapid release of sirolimus from the surface but also improving the PEI coating’s surface hydrophilicity.Based on in vitro cellular response and blood compatibility tests,Ta ion implantation leads to the improvement of endothelial cell adhesion/proliferation and suppression of platelet adhesion/activation regardless of sirolimus loading.These results indicate that the combination of PEI coating and Ta ion implantation has significant innovative potential to provide excellent vascular compatibility and prevent in-stent restenosis and thrombosis.展开更多
Poly(ether imide)(PEI)has shown satisfactory corrosion protection capability with good adhesion strength as a coating for magnesium(Mg),a potential candidate of biodegradable orthopedic implant material.However,its in...Poly(ether imide)(PEI)has shown satisfactory corrosion protection capability with good adhesion strength as a coating for magnesium(Mg),a potential candidate of biodegradable orthopedic implant material.However,its innate hydrophobic property causes insufficient osteoblast affinity and a lack of osseointegration.Herein,we modify the physical and chemical properties of a PEI-coated Mg implant.A plasma immersion ion implantation technique is combined with direct current(DC)magnetron sputtering to introduce biologically compatible tantalum(Ta)onto the surface of the PEI coating.The PEI-coating layer is not damaged during this process owing to the extremely short processing time(30 s),retaining its high corrosion protection property and adhesion stability.The Ta-implanted layer(roughly 10-nm-thick)on the topmost PEI surface generates long-term surface hydrophilicity and favorable surface conditions for pre-osteoblasts to adhere,proliferate,and differentiate.Furthermore,in a rabbit femur study,the Ta/PEI-coated Mg implant demonstrates significantly enhanced bone tissue affinity and osseointegration capability.These results indicate that Ta/PEI-coated Mg is promising for achieving early mechanical fixation and long-term success in biodegradable orthopedic implant applications.展开更多
In recent years,pure iron(Fe)has attracted significant attention as a promising biodegradable orthopedic implant material due to its excellent mechanical and biological properties.However,in physiological conditions,F...In recent years,pure iron(Fe)has attracted significant attention as a promising biodegradable orthopedic implant material due to its excellent mechanical and biological properties.However,in physiological conditions,Fe has an extremely slow degradation rate with localized and irregular degradation,which is problematic for practical applications.In this study,we developed a novel combination of a nanostructured surface topography and galvanic reaction to achieve uniform and accelerated degradation of an Fe implant.The target-ion induced plasma sputtering(TIPS)technique was applied on the Fe implant to introduce biologically compatible and electrochemically noble tantalum(Ta)onto its surface and develop surface nano-galvanic couples.Electrochemical tests revealed that the uniformly distributed nano-galvanic corrosion cells of the TIPS-treated sample(nano Ta-Fe)led to relatively uniform and accelerated surface degradation compared to that of bare Fe.Furthermore,the mechanical properties of nano Ta-Fe remained almost constant during a long-term in vitro immersion test(~40 weeks).Biocompatibility was also assessed on surfaces of bare Fe and nano Ta-Fe using in vitro osteoblast responses through direct and indirect contact assays and an in vivo rabbit femur medullary cavity implantation model.The results revealed that nano Ta-Fe not only enhanced cell adhesion and spreading on its surface,but also exhibited no signs of cellular or tissue toxicity.These results demonstrate the immense potential of Ta-implanted surface nanostructures as an effective solution for the practical application of Fe-based orthopedic implants,ensuring long-term biosafety and clinical efficacy.展开更多
基金supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute(KHIDI)funded by the Ministry of Health&Welfare,Republic of Korea(Grant No:HI18C0493)
文摘Biodegradable stents made of magnesium(Mg)and its alloys have been developed to minimize persistent inflammation or in-stent restenosis,which are the main problems for permanent stents.However,their rapid corrosion behavior under physiological conditions leads to poor vascular compatibility and premature structural failure,which remains an important unsolved clinical problem.Herein,we demonstrate a new strategy for solving this problem by combining poly(ether imide)(PEI)coating and subsequent tantalum(Ta)ion implantation.The PEI coating covers the whole surface of the Mg stent uniformly via a spray coating technique and provides Mg with superior corrosion resistance and stable sirolimus-carrying ability.Ta ion implantation is conducted by a sputtering-based plasma immersion ion implantation technique only onto the luminal surface of the PEI-coated Mg stent.Its extremely short processing time(<30 s)permits preservation of the PEI coating’s corrosion protection ability and sirolimus loading characteristics.In addition,a Ta-implanted skin layer that forms on the topmost surface of the PEI coating plays an effective role in not only preventing a rapid release of sirolimus from the surface but also improving the PEI coating’s surface hydrophilicity.Based on in vitro cellular response and blood compatibility tests,Ta ion implantation leads to the improvement of endothelial cell adhesion/proliferation and suppression of platelet adhesion/activation regardless of sirolimus loading.These results indicate that the combination of PEI coating and Ta ion implantation has significant innovative potential to provide excellent vascular compatibility and prevent in-stent restenosis and thrombosis.
基金a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute(KHIDI)the Ministry of Health&Welfare,Republic of Korea(grant number:HI18C0493).
文摘Poly(ether imide)(PEI)has shown satisfactory corrosion protection capability with good adhesion strength as a coating for magnesium(Mg),a potential candidate of biodegradable orthopedic implant material.However,its innate hydrophobic property causes insufficient osteoblast affinity and a lack of osseointegration.Herein,we modify the physical and chemical properties of a PEI-coated Mg implant.A plasma immersion ion implantation technique is combined with direct current(DC)magnetron sputtering to introduce biologically compatible tantalum(Ta)onto the surface of the PEI coating.The PEI-coating layer is not damaged during this process owing to the extremely short processing time(30 s),retaining its high corrosion protection property and adhesion stability.The Ta-implanted layer(roughly 10-nm-thick)on the topmost PEI surface generates long-term surface hydrophilicity and favorable surface conditions for pre-osteoblasts to adhere,proliferate,and differentiate.Furthermore,in a rabbit femur study,the Ta/PEI-coated Mg implant demonstrates significantly enhanced bone tissue affinity and osseointegration capability.These results indicate that Ta/PEI-coated Mg is promising for achieving early mechanical fixation and long-term success in biodegradable orthopedic implant applications.
基金This study was supported by the Technology Innovation Program(Material parts package business)(No.20001221,Development of high strength and fatigue resistance metal and manufacturing technology for root analogue dental implants)funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea).
文摘In recent years,pure iron(Fe)has attracted significant attention as a promising biodegradable orthopedic implant material due to its excellent mechanical and biological properties.However,in physiological conditions,Fe has an extremely slow degradation rate with localized and irregular degradation,which is problematic for practical applications.In this study,we developed a novel combination of a nanostructured surface topography and galvanic reaction to achieve uniform and accelerated degradation of an Fe implant.The target-ion induced plasma sputtering(TIPS)technique was applied on the Fe implant to introduce biologically compatible and electrochemically noble tantalum(Ta)onto its surface and develop surface nano-galvanic couples.Electrochemical tests revealed that the uniformly distributed nano-galvanic corrosion cells of the TIPS-treated sample(nano Ta-Fe)led to relatively uniform and accelerated surface degradation compared to that of bare Fe.Furthermore,the mechanical properties of nano Ta-Fe remained almost constant during a long-term in vitro immersion test(~40 weeks).Biocompatibility was also assessed on surfaces of bare Fe and nano Ta-Fe using in vitro osteoblast responses through direct and indirect contact assays and an in vivo rabbit femur medullary cavity implantation model.The results revealed that nano Ta-Fe not only enhanced cell adhesion and spreading on its surface,but also exhibited no signs of cellular or tissue toxicity.These results demonstrate the immense potential of Ta-implanted surface nanostructures as an effective solution for the practical application of Fe-based orthopedic implants,ensuring long-term biosafety and clinical efficacy.
