Next-generation craniomaxillofacial implants(CMFIs) are redefining personalized bone reconstruction by balancing and optimizing biomechanics,biocompatibility,and bioactivity—the "3Bs".This review highlights...Next-generation craniomaxillofacial implants(CMFIs) are redefining personalized bone reconstruction by balancing and optimizing biomechanics,biocompatibility,and bioactivity—the "3Bs".This review highlights recent progress in implant design,material development,additive manufacturing,and preclinical evaluation.Emerging biomaterials,including bioresorbable polymers,magnesium alloys,and composites with bioactive ceramics,enable patient-specific solutions with improved safety and functionality.Triply periodic minimal surface(TPMS) architectures exemplify how structural design can enhance both mechanical performance and biological integration.Additive manufacturing technologies further allow the fabrication of geometrically complex,customized impla nts that meet individual anatomical and pathological needs.In parallel,multiscale evaluation techniques—from mechanical testing to in vitro and in vivo models—provide comprehensive insights into implant performance and safety.Looking ahead,the field is poised to benefit from several transformative trends:the development of smart and multifunctional biomaterials;Al-driven design frameworks that leverage patient-specific data and computational modeling;predictive additive manufacturing with real-time quality control;and advanced biological testing platforms for preclinical evaluation.Together,these advances form the foundation of a data-informed,translational pipeline from bench to bedside.Realizing the full potential of nextgene ration CMFIs will require close interdisciplina ry collaboration across mate rials science,computational engineering,and clinical medicine.展开更多
To improve the corrosion resistance of biodegradable Mg alloys,WE43 alloys were implanted with Fe,Ti,Zn and Zr ions at the same implantation dose.The surface morphology,valence state of elements,nano-hardness(NH),elas...To improve the corrosion resistance of biodegradable Mg alloys,WE43 alloys were implanted with Fe,Ti,Zn and Zr ions at the same implantation dose.The surface morphology,valence state of elements,nano-hardness(NH),elastic modulus(EM),degradation rate and in vitro cell experiments of the modified WE43 alloys were systematically studied.A modified layer composed of Mg,MgO,the implanted elements and their oxides was formed on the modified alloys.Since high-speed metal ions caused severe surface lattice damage,the surface hardness of the substrate considerable increased.Electrochemical tests demonstrated a substantial enhancement in the corrosion resistance of the modified alloys via the implantation of Ti and Zr ions,resulting in a reduction of the corrosion current density to 88.1±9.9 and 15.6±11.4μA cm^(−2),respectively,compared with the implantation of Fe and Zn ions.Biocompatibility tests showed that the implantation of Fe,Ti,Zn and Zr ions enhanced the anticoagulant and hemolytic resistance of the WE43 alloy.All surface-modified samples showed negligible cytotoxicity(0-1)at 12.5%extract concentration.Moreover,the alloys implanted with Fe,Ti and Zn ions significantly promoted proliferation of human umbilical vein endothelial cells(HUVEC)compared with the unmodified alloy.The results demonstrate that Ti ion implantation is the best choice for WE43 alloy modification to achieve outstanding corrosion resistance and biocompatibility.展开更多
The possible application of magnesium(Mg)in glaucoma surgical treatment has been investigated in our previous work.In this paper,the degradation behavior and biocompatibility of Mg coated with hydroxyapatite(HA)and di...The possible application of magnesium(Mg)in glaucoma surgical treatment has been investigated in our previous work.In this paper,the degradation behavior and biocompatibility of Mg coated with hydroxyapatite(HA)and dicalcium phosphate dihydrate(DCPD)in eye environment were evaluated,and uncoated Mg was used for comparison.It was found that uniform corrosion occurred macroscopically to the coated Mg samples in sodium lactate ringer’s injection(SLRI)as well as in the rabbit eyes.In micro-scale,the corrosion was characterized by local cracking and pitting primarily.Mg and calcium(Ca)were incorporated into the surface corrosion products and a multi-layer structure was formed.Compared to other samples,HA-coated Mg slowed down dramatically the alkalinity of the solution and the ion release of the sample,and exhibited the lowest corrosion rate in SLRI,which was about 0.22 mm/a.In terms of biocompatibility,fibroblasts demonstrated high viability in the HA-coated and DCPD-coated Mg groups(p<0.05)in vitro.In vivo,HA-coated Mg was found to show lower inflammatory response and fibrosis than the other groups did,as indicated by hematoxylin-eosin and immunofluorescence staining.During the degrading process of HA-coated Mg in the rabbits’eyes,no inflammation was found in the anterior chamber,lens,and vitreous body.HA-coated Mg was fully biodegraded fifteen weeks post-operation,and the scleral drainage channel(SDC)was formed without obvious scarring.It is concluded that HA-coated Mg implantation is a promising adjunctive procedure to improve the success rate of trabeculectomy.Statement of significance:Magnesium(Mg)has shown to be a potential biomaterial for ophthalmic implants in our previous work.However,inflammatory response resulted from the low corrosion resistance of Mg is a major concern.It is shown here that Mg coated with different calcium phosphates can improve these properties in varying degrees and keep the scleral drainage channel unobstructed and unscarred.Based on our in vitro and in vivo studies,HA-coated Mg exhibited a better degradation behavior and excellent biocompatibility.The scleral drainage channel still exists and aqueous humor flows out smoothly after the full degradation of the implant.It is concluded that HA-coated Mg is a promising biomaterial to increase the therapeutic efficiency of trabeculectomy for glaucoma.展开更多
Although the degradability and biosafety of magnesium alloys make them advantageous for biological applications,medical implants made of magnesium alloys often fail prematurely due to corrosion.Therefore,improving the...Although the degradability and biosafety of magnesium alloys make them advantageous for biological applications,medical implants made of magnesium alloys often fail prematurely due to corrosion.Therefore,improving the corrosion resistance of magnesium alloys has become an urgent problem in the alloy design process.In this study,we designed and prepared Mg-xZn-0.5Y-0.5Zr(x=1,2,and 3,wt%)alloys in a hot extruded state and analyzed their surface structure through scanning electron microscopy,energy dispersion spectrometry,and X-ray diffraction.It was found that increasing the Zn content refined the recrystallized grains in the alloy.Particularly in Mg-3Zn-0.5Y-0.5Zr,the I phase became finer,forming both granular and nanoscale needle-like particles.Surface characterization after the immersion experiment showed that the corrosion product layer was mainly composed of Mg(OH)_(2),Zn(OH)_(2),CaCO_(3),and hy-droxyapatite.The degradation rate of ZW305K was the lowest,measured as 4.1 and 6.0 mm·a^(-1) with the hydrogen precipitation method and weight loss method respectively.Electrochemical experiments further explained the corrosion circuit model of the alloy in solution and confirmed the earlier results.The maximum polarization resistance of ZW305K was 874.5Ω·cm^(2),and the lowest corrosion current density was 0.104 mA·cm^(-2).As a biomedical alloy,it must exhibit good biocompatibility,so the alloy was also tested through cytotoxicity,cell adhesion,and staining experiments.The cell viability of each group after 48 h was greater than 80%,showing that the addition of zinc enhances the alloy’s biocompatibility.In summary,the prepared alloys have the potential to be used as biodegradable implant materials.展开更多
Previous work indicated that long-period stacking ordered(LPSO) phase and/or γ’ in rare earth containing Mg biomaterials had contradictory mechanisms responsible for their degradation in less complex or standard sal...Previous work indicated that long-period stacking ordered(LPSO) phase and/or γ’ in rare earth containing Mg biomaterials had contradictory mechanisms responsible for their degradation in less complex or standard salt media, such as 0.9 % NaCl solution. They needed to be further investigated in a more realistic simulated body fluid(SBF). The present work investigated the influence of the amount and types of intermetallics on the degradation behavior of as-cast Mg-xDy-Zn(x = 5, 10, 15 wt.%) alloys using immersion test in Dulbecco's modified Eagle's medium(DMEM) + Glutamax together with 10 % Fetal bovine serum(FBS) under cell culture conditions. It was revealed that the existence of intermetallics exhibited different effects on the degradation behavior of alloys. At the early stage of immersion, Mg-10Dy-1.5Zn alloy suffered the most serious degradation among these three alloys, owing to its more severe micro galvanic corrosion. With the immersion proceeding, the degradation rate of Mg-5Dy-1.5Zn alloy consistently increased because of the scattered distribution of few intermetallics. In contrast, the continuous network structure of intermetallics and a compact degradation layer provided protection from further degradation for Mg-10Dy-1.5Zn and Mg-15Dy-1.5Zn alloys. In the as-cast Mg-5Dy-1.5Zn alloy, only small amount of intermetallics composed of W, γ’ and18R LPSO phases acted as galvanic cathodes, accelerating its degradation. With Dy content increasing to 10 and 15 wt.%, large amounts of intermetallics including 18R LPSO and dense γ’ phases were formed, which on the other hand can serve as a continuous network barrier to retard degradation propagation. Finally, the good adhesion and proliferation of the Human umbilical cord perivascular(HUCPV) on the surface of the Mg-10Dy-1.5Zn and Mg-15Dy-1.5Zn alloy indicated their good biocompatibility.展开更多
To address the limited wear resistance observed in traditional titanium alloys,we have developed an ultrafine-grained equiatomic TiMoNb compositionally complex alloy(CCA)with exceptional wear resistance.However,there ...To address the limited wear resistance observed in traditional titanium alloys,we have developed an ultrafine-grained equiatomic TiMoNb compositionally complex alloy(CCA)with exceptional wear resistance.However,there is a significant lack of in vitro and in vivo evaluation of the TiMoNb CCA for biomedical applications.In this study,we comprehensively evaluate the corrosion behavior,tribo-corrosion performance,biocompatibility,and osseointegration of the TiMoNb alloy.Our findings indicate that the alloy exhibits strong corrosion resistance and stable tribo-corrosion behavior,attributed to the presence of Ti-rich nanoscale precipitates that impede tribo-corrosion-induced shear deformation,along with a protective nanoscale oxide layer.Furthermore,in vitro and in vivo evaluations demonstrate the excellent biocompatibility of the TiMoNb alloy and reveal its ability to promote the regeneration of defective femurs and its favorable bone osseointegration capability.Overall,our study underscores the potential of the TiMoNb alloy as a promising material for dental implants and provides valuable insights into the tribo-corrosion mechanisms of ultrafine-grained alloys.展开更多
Ti-Mo-O alloys were used to analyze the effect of Mo and O contents on the mechanical compatibility and biocompatibility.The bending modulus,bending yield strength and springback ratio of the alloys were evaluated by ...Ti-Mo-O alloys were used to analyze the effect of Mo and O contents on the mechanical compatibility and biocompatibility.The bending modulus,bending yield strength and springback ratio of the alloys were evaluated by using three-point bending tests and bending load-unloading tests.The biocompatibility was investigated by the adhesion,proliferation and the alkaline phosphatase(ALP)activity of mouse osteoblast-like cells(MC3T3-E1).The results showed that the bending modulus and bending yield strength first were increased and then decreased with the increase in Mo content,while the springback ratio exhibited an opposite trend to the bending modulus.With the increase in O content,the bending modulus remained almost constant,while the bending yield strength was increased.The springback ratio exhibited a similar trend to the bending yield strength.The in vitro biological experiments showed that the Ti-Mo-O alloys had excellent biocompatibility due to the formed stable oxide films on their surface.With the increase in O and Mo contents,the TiO_(2)-MoO_(2)oxide film became denser.Combining with mechanical compatibility and biocompatibility,the Ti-15Mo-0.2O and Ti-15Mo-0.3O alloys were more suitable for the biomedical application of spinal fixation device.展开更多
The poor mechanical properties of pure zinc(Zn)restrain its applications in orthopedics,which requires high loading capacity.Alloying with lithium(Li)element can enhance strength,however,the work-hardening rate is imp...The poor mechanical properties of pure zinc(Zn)restrain its applications in orthopedics,which requires high loading capacity.Alloying with lithium(Li)element can enhance strength,however,the work-hardening rate is impaired with increased Li content.Here,introducing scandium(Sc)into a low Li-containing Zn-0.1Li alloy could effectively refine its microstructure,reducing the average grain size from 10 to 4μm.The refinement in microstructure led to a significant improvement in tensile strength,im-proving from 257 MPa of Zn-0.1Li to 341 MPa of Zn-0.1Li-0.1Sc,meanwhile,the work-hardening rate remained positive during the whole plastic deformation stage.The addition of Sc-impaired elongation is due to numerous microcracks formed at the Zn/ScZn_(12)interfaces,as well as in the large-sized ScZn_(12)particles.Corrosion tests revealed an accelerated corrosion rate due to the galvanic effect between the Zn matrix and ScZn_(12)phase.Even so,the Zn-0.1Li-1.0Sc alloy still exhibited superior biocompatibility with rat/mouse mesenchymal stem cells and close osteogenesis capacity to the original Zn-0.1Li alloy.These findings demonstrated that the addition of Sc in low Li-containing alloys could improve mechanical strength without sacrificing the work-hardening rate and biocompatibility.展开更多
Utilizing nanotechnology and composites to create a protective film on titanium alloy is an effective means of achieving the desired high performance.Self-assembly of nanocomposite structures offers a promising route ...Utilizing nanotechnology and composites to create a protective film on titanium alloy is an effective means of achieving the desired high performance.Self-assembly of nanocomposite structures offers a promising route to forming high entropy alloy films(HEAFs),but controlled preparation remains challeng-ing.This work used magnetron sputtering through adjusting preparation parameters to prepare ZrNbTi-CrCu HEAFs,achieving a significant improvement in corrosion resistance and biocompatibility induced by the precipitation of Cu.According to the electrochemical corrosion test,without obvious corrosion pits on the surface of S2 after corrosion,a passivation film composed of bimetallic oxide CuCrO2 formed on the film surface,indicating that ZrNbTiCrCu HEAFs have remarkable corrosion resistance performance.In the cytocompatibility experiment,the cell viability of HEAFs reached over 95%due to the precipitation of Cu,suggesting their excellent biocompatibility.In addition,ZrNbTiCrCu HEAFs exhibit outstanding an-tibacterial ability,especially when the sputtering current is 0.6 A,and the in vitro antibacterial rate of the sample against Escherichia coli is close to 99%.展开更多
In this study,the effect of annealing on the microstructure and following corrosion and biological properties of Mg-1.0Ca-0.5Zn-0.1Y-0.03Mn(at.%)alloy prepared by rapid solidified powder metallurgy was investigated.Th...In this study,the effect of annealing on the microstructure and following corrosion and biological properties of Mg-1.0Ca-0.5Zn-0.1Y-0.03Mn(at.%)alloy prepared by rapid solidified powder metallurgy was investigated.The annealing at 300℃ for 2 h did not change the grain size significantly;however,a slight growth of Mg_(2)Ca precipitates was observed.When the annealing temperature increased up to 400℃ for 2 h,full recrystallization of the alloy occurred;the grains and precipitates grew noticeably.Those changes were responsible for decreasing the corrosion and the tribocorrosion resistance of the alloy.Due to lowered resistance to the corrosion medium,the cell viability was also reduced.Although MG63 cells on the annealed specimens developed filopodia,cell-to-cell communication was not observed.展开更多
Phospahting coated WE43 magnesium alloy was prepared by an immersion method. The microstructure, corrosion resistance and biocompatibility of the coated alloy were investigated. Scanning electron microscopy （SEM） an...Phospahting coated WE43 magnesium alloy was prepared by an immersion method. The microstructure, corrosion resistance and biocompatibility of the coated alloy were investigated. Scanning electron microscopy （SEM） and X-ray diffraction （XRD） were used to examine the microstructure and the composition of the coated alloy. The corrosion resistance was studied by means of potentiodynamic polarization method and the biocompatibility of the surface modified WE43 alloy was evaluated by （3-（4,5）-Dimethylthiazol-2, yl）-2,5-diphenyltetrazolium bromide （MTT） and hemolysis test. The results show that the phosphating coating can enhance the corrosion resistance of WE43 alloy and can be a good candidate to increase the biocompatibility of WE43 alloy.展开更多
A Mg?6%Zn?10%Ca3(PO4)2 composite with a chitosan coating was prepared to study its in vivo biodegradation properties. The chitosan dissolved in a 0.2% acetic acid solution was applied on the surface of Mg?6%Zn?10%Ca3(...A Mg?6%Zn?10%Ca3(PO4)2 composite with a chitosan coating was prepared to study its in vivo biodegradation properties. The chitosan dissolved in a 0.2% acetic acid solution was applied on the surface of Mg?6%Zn?10%Ca3(PO4)2 composite specimens and solidified at 60 °C for 30 min to form the coating. The cytotoxicity evaluation of chitosan coated specimens is at level 0, which indicates that such coating is safe for cellular applications. The in vivotests of chitosan coated composite show that the concentration of metal ions from the composite measured in the venous blood of Zelanian rabbits is less than that from the uncoated composite specimens. The chitosan coating impedes the in vivo degradation of the composite after surgery. The in vivo testing also indicates that the chitosan coated composite is harmless to important visceral organs, including the heart, kidneys and liver of the rabbits. The new bone formation surrounding the chitosan coated composite implant shows that the composite improves the concrescence of the bone tissues. And the chitosan coating is an effective corrosion resistant layer that reduces the hydrogen release of the implant composite, thereby decreasing the subcutaneous gas bubbles formed.展开更多
基金Financial support from National University of Singapore (NUS)(AcRF A-8000-126-00-00)。
文摘Next-generation craniomaxillofacial implants(CMFIs) are redefining personalized bone reconstruction by balancing and optimizing biomechanics,biocompatibility,and bioactivity—the "3Bs".This review highlights recent progress in implant design,material development,additive manufacturing,and preclinical evaluation.Emerging biomaterials,including bioresorbable polymers,magnesium alloys,and composites with bioactive ceramics,enable patient-specific solutions with improved safety and functionality.Triply periodic minimal surface(TPMS) architectures exemplify how structural design can enhance both mechanical performance and biological integration.Additive manufacturing technologies further allow the fabrication of geometrically complex,customized impla nts that meet individual anatomical and pathological needs.In parallel,multiscale evaluation techniques—from mechanical testing to in vitro and in vivo models—provide comprehensive insights into implant performance and safety.Looking ahead,the field is poised to benefit from several transformative trends:the development of smart and multifunctional biomaterials;Al-driven design frameworks that leverage patient-specific data and computational modeling;predictive additive manufacturing with real-time quality control;and advanced biological testing platforms for preclinical evaluation.Together,these advances form the foundation of a data-informed,translational pipeline from bench to bedside.Realizing the full potential of nextgene ration CMFIs will require close interdisciplina ry collaboration across mate rials science,computational engineering,and clinical medicine.
基金supported by National Natural Science Foundation of China(52271117)Educational Commission of Hunan Province of China(23A0107)High Technology Research and Development Program of Hunan Province of China(2022GK4038).
文摘To improve the corrosion resistance of biodegradable Mg alloys,WE43 alloys were implanted with Fe,Ti,Zn and Zr ions at the same implantation dose.The surface morphology,valence state of elements,nano-hardness(NH),elastic modulus(EM),degradation rate and in vitro cell experiments of the modified WE43 alloys were systematically studied.A modified layer composed of Mg,MgO,the implanted elements and their oxides was formed on the modified alloys.Since high-speed metal ions caused severe surface lattice damage,the surface hardness of the substrate considerable increased.Electrochemical tests demonstrated a substantial enhancement in the corrosion resistance of the modified alloys via the implantation of Ti and Zr ions,resulting in a reduction of the corrosion current density to 88.1±9.9 and 15.6±11.4μA cm^(−2),respectively,compared with the implantation of Fe and Zn ions.Biocompatibility tests showed that the implantation of Fe,Ti,Zn and Zr ions enhanced the anticoagulant and hemolytic resistance of the WE43 alloy.All surface-modified samples showed negligible cytotoxicity(0-1)at 12.5%extract concentration.Moreover,the alloys implanted with Fe,Ti and Zn ions significantly promoted proliferation of human umbilical vein endothelial cells(HUVEC)compared with the unmodified alloy.The results demonstrate that Ti ion implantation is the best choice for WE43 alloy modification to achieve outstanding corrosion resistance and biocompatibility.
基金supported by the Natural Science Foundation of Chongqing(Grant No.csts2018jcyjAX0016)Funded by the Senior Medical Talents Program of Chongqing for Young and Middle-aged.
文摘The possible application of magnesium(Mg)in glaucoma surgical treatment has been investigated in our previous work.In this paper,the degradation behavior and biocompatibility of Mg coated with hydroxyapatite(HA)and dicalcium phosphate dihydrate(DCPD)in eye environment were evaluated,and uncoated Mg was used for comparison.It was found that uniform corrosion occurred macroscopically to the coated Mg samples in sodium lactate ringer’s injection(SLRI)as well as in the rabbit eyes.In micro-scale,the corrosion was characterized by local cracking and pitting primarily.Mg and calcium(Ca)were incorporated into the surface corrosion products and a multi-layer structure was formed.Compared to other samples,HA-coated Mg slowed down dramatically the alkalinity of the solution and the ion release of the sample,and exhibited the lowest corrosion rate in SLRI,which was about 0.22 mm/a.In terms of biocompatibility,fibroblasts demonstrated high viability in the HA-coated and DCPD-coated Mg groups(p<0.05)in vitro.In vivo,HA-coated Mg was found to show lower inflammatory response and fibrosis than the other groups did,as indicated by hematoxylin-eosin and immunofluorescence staining.During the degrading process of HA-coated Mg in the rabbits’eyes,no inflammation was found in the anterior chamber,lens,and vitreous body.HA-coated Mg was fully biodegraded fifteen weeks post-operation,and the scleral drainage channel(SDC)was formed without obvious scarring.It is concluded that HA-coated Mg implantation is a promising adjunctive procedure to improve the success rate of trabeculectomy.Statement of significance:Magnesium(Mg)has shown to be a potential biomaterial for ophthalmic implants in our previous work.However,inflammatory response resulted from the low corrosion resistance of Mg is a major concern.It is shown here that Mg coated with different calcium phosphates can improve these properties in varying degrees and keep the scleral drainage channel unobstructed and unscarred.Based on our in vitro and in vivo studies,HA-coated Mg exhibited a better degradation behavior and excellent biocompatibility.The scleral drainage channel still exists and aqueous humor flows out smoothly after the full degradation of the implant.It is concluded that HA-coated Mg is a promising biomaterial to increase the therapeutic efficiency of trabeculectomy for glaucoma.
基金supported by the National Natural Science Foundation of China(Nos.52371070 and 52271249),the Key Research and Development Program of Shaanxi,China(No.2023-YBGY-488)the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University(No.SKLSP202415)Additional support was provided by the Xi’an Talent Plan,China(No.XAYC240016)。
文摘Although the degradability and biosafety of magnesium alloys make them advantageous for biological applications,medical implants made of magnesium alloys often fail prematurely due to corrosion.Therefore,improving the corrosion resistance of magnesium alloys has become an urgent problem in the alloy design process.In this study,we designed and prepared Mg-xZn-0.5Y-0.5Zr(x=1,2,and 3,wt%)alloys in a hot extruded state and analyzed their surface structure through scanning electron microscopy,energy dispersion spectrometry,and X-ray diffraction.It was found that increasing the Zn content refined the recrystallized grains in the alloy.Particularly in Mg-3Zn-0.5Y-0.5Zr,the I phase became finer,forming both granular and nanoscale needle-like particles.Surface characterization after the immersion experiment showed that the corrosion product layer was mainly composed of Mg(OH)_(2),Zn(OH)_(2),CaCO_(3),and hy-droxyapatite.The degradation rate of ZW305K was the lowest,measured as 4.1 and 6.0 mm·a^(-1) with the hydrogen precipitation method and weight loss method respectively.Electrochemical experiments further explained the corrosion circuit model of the alloy in solution and confirmed the earlier results.The maximum polarization resistance of ZW305K was 874.5Ω·cm^(2),and the lowest corrosion current density was 0.104 mA·cm^(-2).As a biomedical alloy,it must exhibit good biocompatibility,so the alloy was also tested through cytotoxicity,cell adhesion,and staining experiments.The cell viability of each group after 48 h was greater than 80%,showing that the addition of zinc enhances the alloy’s biocompatibility.In summary,the prepared alloys have the potential to be used as biodegradable implant materials.
基金the China Scholarship Council for the award of fellowship and funding (nos. 202106890013 and 202206095009)German Academic Exchange Service (DAAD) for the award of fellowship and funding (no. 91870848).
文摘Previous work indicated that long-period stacking ordered(LPSO) phase and/or γ’ in rare earth containing Mg biomaterials had contradictory mechanisms responsible for their degradation in less complex or standard salt media, such as 0.9 % NaCl solution. They needed to be further investigated in a more realistic simulated body fluid(SBF). The present work investigated the influence of the amount and types of intermetallics on the degradation behavior of as-cast Mg-xDy-Zn(x = 5, 10, 15 wt.%) alloys using immersion test in Dulbecco's modified Eagle's medium(DMEM) + Glutamax together with 10 % Fetal bovine serum(FBS) under cell culture conditions. It was revealed that the existence of intermetallics exhibited different effects on the degradation behavior of alloys. At the early stage of immersion, Mg-10Dy-1.5Zn alloy suffered the most serious degradation among these three alloys, owing to its more severe micro galvanic corrosion. With the immersion proceeding, the degradation rate of Mg-5Dy-1.5Zn alloy consistently increased because of the scattered distribution of few intermetallics. In contrast, the continuous network structure of intermetallics and a compact degradation layer provided protection from further degradation for Mg-10Dy-1.5Zn and Mg-15Dy-1.5Zn alloys. In the as-cast Mg-5Dy-1.5Zn alloy, only small amount of intermetallics composed of W, γ’ and18R LPSO phases acted as galvanic cathodes, accelerating its degradation. With Dy content increasing to 10 and 15 wt.%, large amounts of intermetallics including 18R LPSO and dense γ’ phases were formed, which on the other hand can serve as a continuous network barrier to retard degradation propagation. Finally, the good adhesion and proliferation of the Human umbilical cord perivascular(HUCPV) on the surface of the Mg-10Dy-1.5Zn and Mg-15Dy-1.5Zn alloy indicated their good biocompatibility.
基金financially supported by the National Natural Science Foundation of China(Nos.52371251 and 52122102)the Fundamental and Applied Fundamental Research Fund of Guangdong Province(No.2022B1515120082).
文摘To address the limited wear resistance observed in traditional titanium alloys,we have developed an ultrafine-grained equiatomic TiMoNb compositionally complex alloy(CCA)with exceptional wear resistance.However,there is a significant lack of in vitro and in vivo evaluation of the TiMoNb CCA for biomedical applications.In this study,we comprehensively evaluate the corrosion behavior,tribo-corrosion performance,biocompatibility,and osseointegration of the TiMoNb alloy.Our findings indicate that the alloy exhibits strong corrosion resistance and stable tribo-corrosion behavior,attributed to the presence of Ti-rich nanoscale precipitates that impede tribo-corrosion-induced shear deformation,along with a protective nanoscale oxide layer.Furthermore,in vitro and in vivo evaluations demonstrate the excellent biocompatibility of the TiMoNb alloy and reveal its ability to promote the regeneration of defective femurs and its favorable bone osseointegration capability.Overall,our study underscores the potential of the TiMoNb alloy as a promising material for dental implants and provides valuable insights into the tribo-corrosion mechanisms of ultrafine-grained alloys.
基金supported by the National Natural Science Foundation of China(Grant No.52071051)the(Key)Foundation of Xi'an Key Laboratory of High-Performance Titanium Alloy(No.NIN-HTL-2022-ZD01).
文摘Ti-Mo-O alloys were used to analyze the effect of Mo and O contents on the mechanical compatibility and biocompatibility.The bending modulus,bending yield strength and springback ratio of the alloys were evaluated by using three-point bending tests and bending load-unloading tests.The biocompatibility was investigated by the adhesion,proliferation and the alkaline phosphatase(ALP)activity of mouse osteoblast-like cells(MC3T3-E1).The results showed that the bending modulus and bending yield strength first were increased and then decreased with the increase in Mo content,while the springback ratio exhibited an opposite trend to the bending modulus.With the increase in O content,the bending modulus remained almost constant,while the bending yield strength was increased.The springback ratio exhibited a similar trend to the bending yield strength.The in vitro biological experiments showed that the Ti-Mo-O alloys had excellent biocompatibility due to the formed stable oxide films on their surface.With the increase in O and Mo contents,the TiO_(2)-MoO_(2)oxide film became denser.Combining with mechanical compatibility and biocompatibility,the Ti-15Mo-0.2O and Ti-15Mo-0.3O alloys were more suitable for the biomedical application of spinal fixation device.
基金supported by the National Natural Science Foundation of China(Grant Nos.U22A20121 and 52101283)the Suzhou Science and Technology Project(Grant No SJC2023005)+3 种基金the Science and Technology Planning Project of Guangzhou(Grant No 202102010008)the High-Level Hospital Construction Project(Grant No KJ012019520)the Beijing Mu-nicipal Health Commission(BMHC-2021-6,BJRITO-RDP-2024)the Beijing Municipal Public Welfare Development and Reform Pilot Project for Medical Research Institutes(Nos.JYY2023-11 and JYY2023-8).
文摘The poor mechanical properties of pure zinc(Zn)restrain its applications in orthopedics,which requires high loading capacity.Alloying with lithium(Li)element can enhance strength,however,the work-hardening rate is impaired with increased Li content.Here,introducing scandium(Sc)into a low Li-containing Zn-0.1Li alloy could effectively refine its microstructure,reducing the average grain size from 10 to 4μm.The refinement in microstructure led to a significant improvement in tensile strength,im-proving from 257 MPa of Zn-0.1Li to 341 MPa of Zn-0.1Li-0.1Sc,meanwhile,the work-hardening rate remained positive during the whole plastic deformation stage.The addition of Sc-impaired elongation is due to numerous microcracks formed at the Zn/ScZn_(12)interfaces,as well as in the large-sized ScZn_(12)particles.Corrosion tests revealed an accelerated corrosion rate due to the galvanic effect between the Zn matrix and ScZn_(12)phase.Even so,the Zn-0.1Li-1.0Sc alloy still exhibited superior biocompatibility with rat/mouse mesenchymal stem cells and close osteogenesis capacity to the original Zn-0.1Li alloy.These findings demonstrated that the addition of Sc in low Li-containing alloys could improve mechanical strength without sacrificing the work-hardening rate and biocompatibility.
基金the Natural Science Foundation of China(Nos.52205218,52401297)Natural Science Foundation of Shan-dong Province,China(Nos.ZR2020QE024 andZR2021QB015)the Youth Innovation Team Project of Higher Education Institutions in Shandong Province(No.2022KJ272).
文摘Utilizing nanotechnology and composites to create a protective film on titanium alloy is an effective means of achieving the desired high performance.Self-assembly of nanocomposite structures offers a promising route to forming high entropy alloy films(HEAFs),but controlled preparation remains challeng-ing.This work used magnetron sputtering through adjusting preparation parameters to prepare ZrNbTi-CrCu HEAFs,achieving a significant improvement in corrosion resistance and biocompatibility induced by the precipitation of Cu.According to the electrochemical corrosion test,without obvious corrosion pits on the surface of S2 after corrosion,a passivation film composed of bimetallic oxide CuCrO2 formed on the film surface,indicating that ZrNbTiCrCu HEAFs have remarkable corrosion resistance performance.In the cytocompatibility experiment,the cell viability of HEAFs reached over 95%due to the precipitation of Cu,suggesting their excellent biocompatibility.In addition,ZrNbTiCrCu HEAFs exhibit outstanding an-tibacterial ability,especially when the sputtering current is 0.6 A,and the in vitro antibacterial rate of the sample against Escherichia coli is close to 99%.
基金funded by the National Centre for Research and Development in Poland, project V4-JAPAN/2/15 “Development of Advanced Magnesium Alloys for Multifunctional Applications in Extreme Environments,” under statutory work at the Faculty of Material Science and Engineering Warsaw University of Technology in Polandthe International Visegrad Fund (project no. JP39421, V4Japan Joint Research Program)+3 种基金the support of the International Visegrad Fund (project V4Japan Joint Research Program, Ref. JP3936)the National Research, Development and Innovation Office (contract no. 2019-2.1.7-ERA-NET-2021-00030)Support by the Ministry of Education, Youth and Sports of the Czech Republic in the framework of Visegrad Group (V4)-Japan Joint Research Program-Advanced Materials under grant no. 8F21011 is gratefully acknowledged by K.M., D.D., and A.Fthe support from the Department of Metal and Corrosion Engineering, University of Chemical Technology, Prague, Czech Republic, while performing the tribocorrosion measurements
文摘In this study,the effect of annealing on the microstructure and following corrosion and biological properties of Mg-1.0Ca-0.5Zn-0.1Y-0.03Mn(at.%)alloy prepared by rapid solidified powder metallurgy was investigated.The annealing at 300℃ for 2 h did not change the grain size significantly;however,a slight growth of Mg_(2)Ca precipitates was observed.When the annealing temperature increased up to 400℃ for 2 h,full recrystallization of the alloy occurred;the grains and precipitates grew noticeably.Those changes were responsible for decreasing the corrosion and the tribocorrosion resistance of the alloy.Due to lowered resistance to the corrosion medium,the cell viability was also reduced.Although MG63 cells on the annealed specimens developed filopodia,cell-to-cell communication was not observed.
基金Project(2011AA030103) supported by the National High-tech Research Program of ChinaProject(201001C0104669453) supported by the Guangdong Innovation R&D Team Project,China
文摘Phospahting coated WE43 magnesium alloy was prepared by an immersion method. The microstructure, corrosion resistance and biocompatibility of the coated alloy were investigated. Scanning electron microscopy （SEM） and X-ray diffraction （XRD） were used to examine the microstructure and the composition of the coated alloy. The corrosion resistance was studied by means of potentiodynamic polarization method and the biocompatibility of the surface modified WE43 alloy was evaluated by （3-（4,5）-Dimethylthiazol-2, yl）-2,5-diphenyltetrazolium bromide （MTT） and hemolysis test. The results show that the phosphating coating can enhance the corrosion resistance of WE43 alloy and can be a good candidate to increase the biocompatibility of WE43 alloy.
基金Project(2014)supported by the Open Fund of the State Key Laboratory of Powder Metallurgy,China
文摘A Mg?6%Zn?10%Ca3(PO4)2 composite with a chitosan coating was prepared to study its in vivo biodegradation properties. The chitosan dissolved in a 0.2% acetic acid solution was applied on the surface of Mg?6%Zn?10%Ca3(PO4)2 composite specimens and solidified at 60 °C for 30 min to form the coating. The cytotoxicity evaluation of chitosan coated specimens is at level 0, which indicates that such coating is safe for cellular applications. The in vivotests of chitosan coated composite show that the concentration of metal ions from the composite measured in the venous blood of Zelanian rabbits is less than that from the uncoated composite specimens. The chitosan coating impedes the in vivo degradation of the composite after surgery. The in vivo testing also indicates that the chitosan coated composite is harmless to important visceral organs, including the heart, kidneys and liver of the rabbits. The new bone formation surrounding the chitosan coated composite implant shows that the composite improves the concrescence of the bone tissues. And the chitosan coating is an effective corrosion resistant layer that reduces the hydrogen release of the implant composite, thereby decreasing the subcutaneous gas bubbles formed.
