Five pure metals including Fe, Mn, Mg, Zn and W have been investigated on their corrosion behavior and in vitro biocompatibility by electrochemical measurement, static immersion test, contact angle measurement, cytoto...Five pure metals including Fe, Mn, Mg, Zn and W have been investigated on their corrosion behavior and in vitro biocompatibility by electrochemical measurement, static immersion test, contact angle measurement, cytotoxicity and hemocompatibility tests. It is found that the sequence of corrosion rate of five metals in Hank＇s solution from high to low is： Mg 〉 Fe 〉 Zn 〉 Mn 〉 W. Fe, Mg and W show no cytotoxicity to L929 and ECV304 cells, Mn induces significant cytotoxicity to both L929 and ECV304 cells, and Zn has almost no inhibition effect on the metabolic activities of ECV304 while largely reduces the cell viability of L929 cells. The hemolysis percentage of five pure metals is lower than 5% except for Mg and platelets adhered on Zn has been activated and pseudopodia-like structures can be observed while platelets on the other four metals keep normal.展开更多
In this work, three widely used commercial Zn alloys （ZA4-1, ZA4-3, ZA6-1 ） were purchased and pre- pared by hot extrusion at 200℃. The microstructure, mechanical properties, corrosion behaviors, biocompatibility a...In this work, three widely used commercial Zn alloys （ZA4-1, ZA4-3, ZA6-1 ） were purchased and pre- pared by hot extrusion at 200℃. The microstructure, mechanical properties, corrosion behaviors, biocompatibility and hemocompatibility of Zn alloys were studied with pure Zn as control, Commercial Zn alloys demonstrated increased strength and superb elongation compared with pure Zn. Accelerated corrosion rates and uniform corrosion morphologies were observed in terms of commercial Zn alloys due to galvanic effects between Zn matrix and α-Al phases. 100% extracts of ZA4-1 and ZA6-1 alloys showed mild cytotoxicity while 50% extracts of all samples displayed good biocompatibility. Retardant cell cycle and inhibited stress fibers expression were observed induced by high concentration of Zn^2＋ releasing during corrosion. The hemolysis ratios of Zn alloys were lower than 1% while the adhered platelets showed slightly activated morphologies. In general, commercial Zn alloys possess promising mechanical properties, appropriate corrosion rates, significantly improved biocompatibility and good hemocompatibility in comparison to pure Zn. It is feasible to develop biodegradable metals based on commercial Zn alloys.展开更多
In this work,a series of biodegradable pure iron,Fe–30Mn and Fe–30Mn–Ag alloys were developed by using a rapid solidification technology.A fine a-Fe dendrite was formed in pure iron,resulting in a high compressive ...In this work,a series of biodegradable pure iron,Fe–30Mn and Fe–30Mn–Ag alloys were developed by using a rapid solidification technology.A fine a-Fe dendrite was formed in pure iron,resulting in a high compressive yield strength of above 300 MPa.The Fe–30Mn alloy doped with only 1%Ag exhibited a significant increase in the degradation rate in simulated body fluid due to the precipitation of Ag-rich particles in alloy matrix and the induction of the microgalvanic corrosion.In addition,the novel Fe–30Mn–Ag alloy also exhibited a good magnetic compatibility and offered a closely approaching requirement for biodegradable medical applications.展开更多
Over the past two decades,advances in pediatric orthopedics and closed reduction combined with percutaneous internal fixation techniques have led to significant growth in pediatric orthopedics surgery.Implants such as...Over the past two decades,advances in pediatric orthopedics and closed reduction combined with percutaneous internal fixation techniques have led to significant growth in pediatric orthopedics surgery.Implants such as Kirschner-wires,cannulated screws and elastic stabilization intramedullary nails are commonly used in these procedures.However,traditional implants made of metal or inert materials are not absorbable,leading to complications that affect treatment outcomes.To address this issue,absorbable materials with excellent me-chanical properties,good biocompatibility,and controlled degradation rates have been developed and applied in clinical practice.These materials include absorbable polymers and biodegradable metals.This article provides a comprehensive summary of these resorbable materials from a clinician’s perspective.In addition,an in-depth discussion of the feasibility of their clinical applications and related research in pediatric orthopedics is included.We found that the applications of absorbable implants in pediatric orthopedics are shifting from absorbable polymers to biodegradable metals and emphasize that the functional characteristics of resorbable materials must be coordinated and complementary to the treatment in pediatric orthopedics.展开更多
Recently,zinc and its alloys have been proposed as promising candidates for biodegradable metals(BMs),owning to their preferable corrosion behavior and acceptable biocompatibility in cardiovascular,bone and gastrointe...Recently,zinc and its alloys have been proposed as promising candidates for biodegradable metals(BMs),owning to their preferable corrosion behavior and acceptable biocompatibility in cardiovascular,bone and gastrointestinal environments,together with Mg-based and Fe-based BMs.However,there is the desire for surface treatment for Zn-based BMs to better control their biodegradation behavior.Firstly,the implantation of some Zn-based BMs in cardiovascular environment exhibited intimal activation with mild inflammation.Secondly,for orthopedic applications,the biodegradation rates of Zn-based BMs are relatively slow,resulting in a long-term retention after fulfilling their mission.Meanwhile,excessive Zn2+release during degradation will cause in vitro cytotoxicity and in vivo delayed osseointegration.In this review,we firstly summarized the current surface modification methods of Zn-based alloys for the industrial applications.Then we comprehensively summarized the recent progress of biomedical bulk Zn-based BMs as well as the corresponding surface modification strategies.Last but not least,the future perspectives towards the design of surface bio-functionalized coatings on Zn-based BMs for orthopedic and cardiovascular applications were also briefly proposed.展开更多
The oral and maxillofacial regions have complex anatomical structures and different tissue types,which have vital health and aesthetic functions.Biodegradable metals(BMs)is a promising bioactive materials to treat ora...The oral and maxillofacial regions have complex anatomical structures and different tissue types,which have vital health and aesthetic functions.Biodegradable metals(BMs)is a promising bioactive materials to treat oral and maxillofacial diseases.This review summarizes the research status and future research directions of BMs for oral and maxillofacial applications.Mg-based BMs and Zn-based BMs for bone fracture fixation systems,and guided bone regeneration(GBR)membranes,are discussed in detail.Zn-based BMs with a moderate degradation rate and superior mechanical properties for GBR membranes show great potential for clinical translation.Fe-based BMs have a relatively low degradation rate and insoluble degradation products,which greatly limit their application and clinical translation.Furthermore,we proposed potential future research directions for BMs in the oral and maxillofacial regions,including 3D printed BM bone scaffolds,surface modification for BMs GBR membranes,and BMs containing hydrogels for cartilage regeneration,soft tissue regeneration,and nerve regeneration.Taken together,the progress made in the development of BMs in oral and maxillofacial regions has laid a foundation for further clinical translation.展开更多
Biodegradable metals are promising candidates for bone defect repair.With an evidence-based approach,this study investigated and analyzed the performance and degradation properties of biodegradable metals in animal mo...Biodegradable metals are promising candidates for bone defect repair.With an evidence-based approach,this study investigated and analyzed the performance and degradation properties of biodegradable metals in animal models for bone defect repair to explore their potential clinical translation.Animal studies on bone defect repair with biodegradable metals in comparison with other traditional biomaterials were reviewed.Data was carefully collected after identification of population,intervention,comparison,outcome,and study design(PICOS),and following the inclusion criteria of biodegradable metals in animal studies.30 publications on pure Mg,Mg alloys,pure Zn and Zn alloys were finally included after extraction from a collected database of 2543 publications.A qualitative systematic review and a quantitative meta-analysis were performed.Given the heterogeneity in animal model,anatomical site and critical size defect(CSD),biodegradable metals exhibited mixed effects on bone defect repair and degradation in animal studies in comparison with traditional non-degradable metals,biodegradable polymers,bioceramics,and autogenous bone grafts.The results indicated that there were limitations in the experimental design of the included studies,and quality of the evidence presented by the studies was very low.To enhance clinical translation of biodegradable metals,evidence-based research with data validity is needed.Future studies should adopt standardized experimental protocols in investigating the effects of biodegradable metals on bone defect repair with animal models.展开更多
Tracheobronchial obstruction in children due to benign stenosis or tracheobronchomalacia still remains a challenging matter of concern.Currently,there is 10%–20%complication rate in clinical treatment.The nonbiodegra...Tracheobronchial obstruction in children due to benign stenosis or tracheobronchomalacia still remains a challenging matter of concern.Currently,there is 10%–20%complication rate in clinical treatment.The nonbiodegradable property of silicone stents and nickel-titanium memory alloy stents take the primary responsibility for drawbacks including stimulating local granulation tissue proliferation,displacement,and stent-related infections.Permanent tracheobronchial stent will be a persistent foreign object for a long time,causing excessive secretion of tracheal mucosa,ulceration and even perforation,which is particularly unsuitable for young children with persistent tracheal growth.In this study,the degradation and biocompatibility performance of three typical biodegradable metals were investigated as potential tracheobronchial stent materials.The results exhibited that these materials showed different degradation behaviors in the simulating respiratory fluid environment compared with SBF.Except for pure iron group,high purity magnesium and zinc showed favorable cell adhesion and proliferation in three culture methodologies(direct culture,indirect culture and extraction culture).The proper corrosion rate and good biocompatibility indicated that high purity magnesium and zinc may be good candidates as tracheobronchial stent materials.展开更多
Over the past two decades,biodegradable metals(BMs)have emerged as promising materials to fabricate temporary biomedical devices,with the purpose of avoiding potential side effects of permanent implants.In this review...Over the past two decades,biodegradable metals(BMs)have emerged as promising materials to fabricate temporary biomedical devices,with the purpose of avoiding potential side effects of permanent implants.In this review,we first surveyed the current status of BMs in neuroscience,and briefly summarized the representative stents for treating vascular stenosis.Then,inspired by the convincing clinical evidence on the in vivo safety of Mg alloys as cardiovascular stents,we analyzed the possibility of producing biodegradable cerebrovascular Mg alloy stents for treating ischemic stroke.For these novel applications,some key factors should also be considered in designing BM brain stents,including the anatomic features of the cerebral vasculature,hemodynamic influences,neuro-cytocompatibility and selection of alloying elements.This work may provide insights into the future design and fabrication of BM neurological devices,especially for brain stents.展开更多
Biodegradable metals offer a promising means to ameliorate many of the long-term risks associated with vascular devices made of conventional biostable stent metals.While numerous biodegradable metal alloys have been d...Biodegradable metals offer a promising means to ameliorate many of the long-term risks associated with vascular devices made of conventional biostable stent metals.While numerous biodegradable metal alloys have been developed and characterized in animal models,knowledge of their blood reactivity and thrombogenicity remains unknown.Metal hemocompatibility is particularly valuable because current generation drug-eluting stents pose a significant long-term thrombosis risk.In this study,four pure metals,widely used as degradable base materials(Fe,Zn,Mg,and Mo),and three alloys commonly used in cardiovascular devices[NiTi,CoCr,and stainless steel(SS)]were evaluated.This work examined how each of these metals activate platelets,coagulation factors,and inflammation using in vitro hemocompatibility assays and a clinically relevant ex vivo non-human primate arteriovenous shunt model.Testing found that while all metals promoted a downstream activation of platelets and coagulation in flowing whole blood,platelet and fibrin attachment to Mg was markedly reduced.Additionally,Fe and Mo trended toward higher platelet attachment and contact pathway activation.Overall,the results suggest that Mg may delay clot initiation,but not eliminate clot formation,indicating the importance of understanding thrombosis in Mg alloys that are currently being developed for clinical use as biodegradable stents.展开更多
Biodegradable metals,designed to be safely degraded and absorbed by the body after fulfil the intended functions,are of particular interest in the 21st century.The marriage of advanced biodegradable metals with clinic...Biodegradable metals,designed to be safely degraded and absorbed by the body after fulfil the intended functions,are of particular interest in the 21st century.The marriage of advanced biodegradable metals with clinical needs have yield unprecedented possibility.Magnesium,iron,and zinc-based materials constitute the main components of temporary,implantable metallic medical devices.A burgeoning number of studies on biodegradable metals have driven the clinical translation of biodegradable metallic devices in the fields of cardiology and orthopaedics over the last decade.Their ability to degrade as well as their beneficial biological functions elicited during degradation endow this type of material with the potential to shift the paradigm in the treatment of musculoskeletal and cardiovascular diseases.This review provides an insight into the degradation mechanism of these metallic devices in specific application sites and introduces state-of-the-art translational research in the field of biodegradable metals,as well as highlighting some challenges for materials design strategies in the context of mechanical and biological compatibility.展开更多
Biodegradable metals have garnered considerable interest owing to their capacity for self-degradation following the repair of damaged tissues.This review commences with their historical development and clarifies the e...Biodegradable metals have garnered considerable interest owing to their capacity for self-degradation following the repair of damaged tissues.This review commences with their historical development and clarifies the essential prerequisites for their successful clinical translation.Subsequently,a detailed review of magnesium-based materials is presented from five critical areas of alloying,fabrication techniques,purification,surface modification,and structural design,systematically addressing their progress in biodegradation rate retardation,mechanical reinforcement,and biocompatibility enhancement.Furthermore,recent breakthroughs in vivo animal experiments and clinical translation of magnesium alloys are summarized.Finally,this review concludes with a critical assessment of the achievements and challenges encountered in the clinical application of these materials,and proposes practical strategies to address current limitations and guide future research perspectives.展开更多
Rare earth （RE） metals are widely used as the alloying implants. However, corrosion behavior of pure RE elements in biodegradable magnesium alloys as medical metals not only in physiological media but also in chlori...Rare earth （RE） metals are widely used as the alloying implants. However, corrosion behavior of pure RE elements in biodegradable magnesium alloys as medical metals not only in physiological media but also in chlorinated saline environment is not well understood. In the present work, the RE metals Y, Nd, Gd and Dy are selected to investigate their corrosion behavior in 0.1 mol/L NaCI solution with immersion and electrochemistry techniques. As indicated, corrosion of the currently investigated RE metals is promoted in the order of Dy, Y, Gd and Nd. In terms of electrochemical response, such a sequence correlates with the increased impedance and the decreased corrosion rate （CR）. These RE metals manifest weak ability for passivation in the native surface. Then, reaction with aqueous solution easily happens through the anodic dissolution and cathodic hydrogen evolution. The corrosion products, RE（OH）3, adhered on the surface of RE metals, do not have an appreciable power to resist the reaction proceeding with corrosive chloride ions. In contrast to pure Mg, the RE metals, including Y, Nd, Gd and Dy, exhibit significantly fragile corrosion resistance in saline media. Therefore, with the curr correlation of corrosion resistance between RE-contain ent findings, it is impossible to reveal a well-defined ng Mg alloy and RE metal itself展开更多
Corrodible metals are the newest kind of biodegradable materials and raise a new problem of the corrosion products.However,the removal of the precipitated products has been unclear and even largely ignored in publicat...Corrodible metals are the newest kind of biodegradable materials and raise a new problem of the corrosion products.However,the removal of the precipitated products has been unclear and even largely ignored in publications.Herein,we find that albumin,an abundant macromolecule in serum,enhances the solubility of corrosion products of iron in blood mimetic Hank’s solution significantly.This is universal for other main biodegradable metals such as magnesium,zinc and polyester-coated iron.Albumin also influences corrosion rates in diverse trends in Hank’s solution and normal saline.Based on quantitative study theoretically and experimentally,both the effects on corrosion rates and soluble fractions are interpreted by a unified mechanism,and the key factor leading to different corrosion behaviors in corrosion media is the interference of albumin to the Ca/P passivation layer on the metal surface.This work has illustrated that the interactions between metals and media macromolecules should be taken into consideration in the design of the next-generation metal-based biodegradable medical devices in the formulism of precision medicine.The improved Hank’s solution in the presence of albumin and with a higher content of initial calcium salt is suggested to access biodegradable metals potentially for cardiovascular medical devices,where the content of calcium salt is calculated after consideration of chelating of calcium ions by albumin,resulting in the physiological concentration of free calcium ions.展开更多
Zinc (Zn)-based biodegradable metals (BMs) fabricated through conventional manufacturing methods exhibit adequate mechanical strength, moderate degradation behavior, acceptable biocompatibility, and bioactive function...Zinc (Zn)-based biodegradable metals (BMs) fabricated through conventional manufacturing methods exhibit adequate mechanical strength, moderate degradation behavior, acceptable biocompatibility, and bioactive functions. Consequently, they are recognized as a new generation of bioactive metals and show promise in several applications. However, conventional manufacturing processes face formidable limitations for the fabrication of customized implants, such as porous scaffolds for tissue engineering, which are future direction towards precise medicine. As a metal additive manufacturing technology, laser powder bed fusion (L-PBF) has the advantages of design freedom and formation precision by using fine powder particles to reliably fabricate metallic implants with customized structures according to patient-specific needs. The combination of Zn-based BMs and L-PBF has become a prominent research focus in the fields of biomaterials as well as biofabrication. Substantial progresses have been made in this interdisciplinary field recently. This work reviewed the current research status of Zn-based BMs manufactured by L-PBF, covering critical issues including powder particles, structure design, processing optimization, chemical compositions, surface modification, microstructure, mechanical properties, degradation behaviors, biocompatibility, and bioactive functions, and meanwhile clarified the influence mechanism of powder particle composition, structure design, and surface modification on the biodegradable performance of L-PBF Zn-based BM implants. Eventually, it was closed with the future perspectives of L-PBF of Zn-based BMs, putting forward based on state-of-the-art development and practical clinical needs.展开更多
Due to its excellent biocompatibility and biodegradability,Mg has received widespread attention in biomaterials as implants and even biobatteries.However,the poor corrosion resistance makes it difficult to meet the gr...Due to its excellent biocompatibility and biodegradability,Mg has received widespread attention in biomaterials as implants and even biobatteries.However,the poor corrosion resistance makes it difficult to meet the growing demand for implant materials.This study developed a biodegradable nano-heterogeneous Mg(48 wt%)-Zn(52 wt%)-based metal(NHMZ)comprising nanocrystalline matrix phase Mg_(51)Zn_(20) and nanoscale MgZn_(2) precipitates.The unique microstructure of NHMZ enhances its corrosion resistance.The spherical aberration-corrected transmission electron microscope(AC-TEM)and precession electron diffraction(PED)characterized the microstructures.The corrosion rate of NHMZ is about 0.21 mm y^(-1) after soaking for 4 weeks,approximately 58% of high pure Mg.In addition,the anode discharge of NHMZ is more stable than Mg,indicating it has great potential in biological batteries.This work hopes to broaden the development direction of biodegradable metallic materials and break through the performance limitation of current biodegradable Mg alloys.展开更多
Extensive in vitro corrosion test systems have been carried out to simulate the in vivo corrosion behavior of biodegradable metallic materials. Various methods have their own unique benefits and limitations. The corro...Extensive in vitro corrosion test systems have been carried out to simulate the in vivo corrosion behavior of biodegradable metallic materials. Various methods have their own unique benefits and limitations. The corrosion mechanism of biodegradable alloys and in vitro corrosion test systems on biodegradable metallic materials are reviewed, to build a reasonable simulated in vitro test system for mimicking the in vivo animal test from the aspects of electrolyte solution selection, surface roughness influence, test methods and evaluation methodology of corrosion rate. Buffered simulated body fluid containing similar components to human blood plasma should be applied as electrolyte solution, such as simulated body fluid （SBF） and culture medium with serum. Surface roughness of samples and ratio of solution volume to sample surface area should be adopted based on the real implant situation, and the dynamic corrosion is preferred. As to the evaluation methodology of corrosion rate, different methods may complement one another.展开更多
Zinc(Zn) and its alloys have been proposed as biodegradable implant materials due to their unique combination of biodegradability, biocompatibility, and biofunctionality. However, the insufficient mechanical propertie...Zinc(Zn) and its alloys have been proposed as biodegradable implant materials due to their unique combination of biodegradability, biocompatibility, and biofunctionality. However, the insufficient mechanical properties of pure Zn greatly limit its clinical application. Here, we report on the microstructure, mechanical properties, friction and wear behavior, corrosion and degradation properties, hemocompatibility, and cytocompatibility of Zn–3 Cu and Zn–3 Cu–0.2 Ti alloys under three different conditions of as-cast(AC),hot-rolling(HR), and hot-rolling plus cold-rolling(HR + CR). The HR + CR Zn–3 Cu–0.2 Ti exhibited the best set of comprehensive properties among all the alloy samples, with yield strength of 211.0 MPa, ultimate strength of 271.1 MPa, and elongation of 72.1 %. Immersion tests of the Zn–3 Cu and Zn–3 Cu–0.2 Ti alloys in Hanks’ solution for 3 months indicated that the AC samples showed the lowest degradation rate,followed by the HR samples, and then the HR + CR samples, while the HR + CR Zn–3 Cu exhibited the highest degradation rate of 23.9 m/a. Friction and wear testing of the Zn–3 Cu and Zn–3 Cu–0.2 Ti alloys in Hanks’ solution indicated that the AC samples showed the highest wear resistance, followed by the HR samples, and then the HR + CR samples, while the AC Zn–3 Cu–0.2 Ti showed the highest wear resistance.The diluted extracts of HR + CR Zn–3 Cu and Zn–3 Cu–0.2 Ti at a concentration of ≤25 % exhibited noncytotoxicity. Furthermore, both the HR + CR Zn–3 Cu and Zn–3 Cu–0.2 Ti exhibited effective antibacterial properties against S. aureus.展开更多
The burst release of Zn 2+from the naked pure Zn and Zn-based alloys could induce local and sys-temic toxicity,which limits their clinical applications as biodegradable implants.In order to inhibit the explosive relea...The burst release of Zn 2+from the naked pure Zn and Zn-based alloys could induce local and sys-temic toxicity,which limits their clinical applications as biodegradable implants.In order to inhibit the explosive release of zinc ions,a protective Ca-P coating was synthesized on biodegradable Zn al-loy.The microstructure,corrosion resistance,antibacterial activity,and biosafety of the Ca-P coating are systematically investigated.Electrochemical tests revealed that Ca-P protective layer has enhanced the anti-corrosion behavior of Zn alloy.Furthermore,Ca-P protective layer showed good biocompatibility,as demonstrated by significantly increased cell viability,good attachment,and spreading at a higher cell density.Besides,the Ca-P coating could also retain the antibacterial ability and inhibit the bacterial ad-hesion.The Ca-P protective layer synthesized on biodegradable Zn alloy can be considered and applied in future biomedical applications.展开更多
The implants made of metallic biomaterials help healing the bone fracture but also affect the bone repair process.As proposed in Matter 4(2021)2548–2650 by Wang et al.,a precisely adaptable biomaterial ought to recap...The implants made of metallic biomaterials help healing the bone fracture but also affect the bone repair process.As proposed in Matter 4(2021)2548–2650 by Wang et al.,a precisely adaptable biomaterial ought to recapitulate the targeted tissue with spatiotemporal precision and hierarchical accuracy,ranging from atoms and molecules(genes,proteins,etc.)to cells(including organelles)and to tissues and organs.In comparison to traditional bio-inert metallic bone implants such as Co-based alloys and Ti alloys,biodegradable metal(Mg and Zn alloys)bone implants had been developed and might arise many unexpected variables in the bone repair,due to their bioactive nature.In this paper,the bone repair without and with the presence of metallic implants is compared.Thereafter,the perspectives concerning the interactions between the bone tissues and biodegradable metal implants are put forward,and how to better mimic in vivo biodegradation by in vitro experiments is proposed for further research and development of biodegradable metals.展开更多
基金supported by the National Basic Research Program of China(973 Program)(Nos.2012CB619102 and 2012CB619100)the Research Fund for the Doctoral Program of Higher Education(No.20100001110011)+2 种基金the National Science Fund for Distinguished Young Scholars(No.51225101)the National Natural Science Foundation of China(No.31170909)the Guangdong Innovative Research Team Program(No. 201001C0104669453)
文摘Five pure metals including Fe, Mn, Mg, Zn and W have been investigated on their corrosion behavior and in vitro biocompatibility by electrochemical measurement, static immersion test, contact angle measurement, cytotoxicity and hemocompatibility tests. It is found that the sequence of corrosion rate of five metals in Hank＇s solution from high to low is： Mg 〉 Fe 〉 Zn 〉 Mn 〉 W. Fe, Mg and W show no cytotoxicity to L929 and ECV304 cells, Mn induces significant cytotoxicity to both L929 and ECV304 cells, and Zn has almost no inhibition effect on the metabolic activities of ECV304 while largely reduces the cell viability of L929 cells. The hemolysis percentage of five pure metals is lower than 5% except for Mg and platelets adhered on Zn has been activated and pseudopodia-like structures can be observed while platelets on the other four metals keep normal.
基金supported by the National Basic Research Program of China (973 Program) (Grant Nos. 2012CB619102 and 012CB619100)National Science Fund for Distinguished Young Scholars (Grant No. 51225101)+3 种基金National Natural Science Foundation of China (Grant Nos. 51431002 and 31170909)the NSFC/RGC Joint Research Scheme (Grant No. 51361165101)State Key Laboratory for Mechanical Behavior of Materials (Grant No. 20141615)Beijing Municipal Science and Technology Project (No. Z141100002814008)
文摘In this work, three widely used commercial Zn alloys （ZA4-1, ZA4-3, ZA6-1 ） were purchased and pre- pared by hot extrusion at 200℃. The microstructure, mechanical properties, corrosion behaviors, biocompatibility and hemocompatibility of Zn alloys were studied with pure Zn as control, Commercial Zn alloys demonstrated increased strength and superb elongation compared with pure Zn. Accelerated corrosion rates and uniform corrosion morphologies were observed in terms of commercial Zn alloys due to galvanic effects between Zn matrix and α-Al phases. 100% extracts of ZA4-1 and ZA6-1 alloys showed mild cytotoxicity while 50% extracts of all samples displayed good biocompatibility. Retardant cell cycle and inhibited stress fibers expression were observed induced by high concentration of Zn^2＋ releasing during corrosion. The hemolysis ratios of Zn alloys were lower than 1% while the adhered platelets showed slightly activated morphologies. In general, commercial Zn alloys possess promising mechanical properties, appropriate corrosion rates, significantly improved biocompatibility and good hemocompatibility in comparison to pure Zn. It is feasible to develop biodegradable metals based on commercial Zn alloys.
基金financially supported by the National Natural Science Foundation of China (No. 51671162)the Fundamental Research Funds for the Central Universities (Nos. XDJK2017B054 and XDJK2017D012)+1 种基金the Chongqing Research Program of Basic Research and Frontier Technology (No. cstc2015jcyj BX0107)the Venture and Innovation Support Program for Chongqing Overseas Returnees
文摘In this work,a series of biodegradable pure iron,Fe–30Mn and Fe–30Mn–Ag alloys were developed by using a rapid solidification technology.A fine a-Fe dendrite was formed in pure iron,resulting in a high compressive yield strength of above 300 MPa.The Fe–30Mn alloy doped with only 1%Ag exhibited a significant increase in the degradation rate in simulated body fluid due to the precipitation of Ag-rich particles in alloy matrix and the induction of the microgalvanic corrosion.In addition,the novel Fe–30Mn–Ag alloy also exhibited a good magnetic compatibility and offered a closely approaching requirement for biodegradable medical applications.
基金the Fujian Natural Science Foundation Project(2024J011287,2022J011311)Fuzhou Health Commission Young&Mid-Career Investigator Research Project(2024-S-rc4)+2 种基金National Natural Science Foundation of China(U22A20121,52401304)Guangdong Basic and Applied Basic Research Foundation(2023A1515110522)Key Clinical Specialty Discipline Construction Program of Fuzhou,Fujian(20220104).
文摘Over the past two decades,advances in pediatric orthopedics and closed reduction combined with percutaneous internal fixation techniques have led to significant growth in pediatric orthopedics surgery.Implants such as Kirschner-wires,cannulated screws and elastic stabilization intramedullary nails are commonly used in these procedures.However,traditional implants made of metal or inert materials are not absorbable,leading to complications that affect treatment outcomes.To address this issue,absorbable materials with excellent me-chanical properties,good biocompatibility,and controlled degradation rates have been developed and applied in clinical practice.These materials include absorbable polymers and biodegradable metals.This article provides a comprehensive summary of these resorbable materials from a clinician’s perspective.In addition,an in-depth discussion of the feasibility of their clinical applications and related research in pediatric orthopedics is included.We found that the applications of absorbable implants in pediatric orthopedics are shifting from absorbable polymers to biodegradable metals and emphasize that the functional characteristics of resorbable materials must be coordinated and complementary to the treatment in pediatric orthopedics.
基金This work was supported by the National Natural Science Foundation of China(Grant No.51931001,51901003)the International Cooperation and Exchange project between NSFC(China)and CNR(Italy)(NSFC-CNR Grant No.52011530392)the Open Project of NMPA Key Laboratory for Dental Materials(Grant No.PKUSS20200401).
文摘Recently,zinc and its alloys have been proposed as promising candidates for biodegradable metals(BMs),owning to their preferable corrosion behavior and acceptable biocompatibility in cardiovascular,bone and gastrointestinal environments,together with Mg-based and Fe-based BMs.However,there is the desire for surface treatment for Zn-based BMs to better control their biodegradation behavior.Firstly,the implantation of some Zn-based BMs in cardiovascular environment exhibited intimal activation with mild inflammation.Secondly,for orthopedic applications,the biodegradation rates of Zn-based BMs are relatively slow,resulting in a long-term retention after fulfilling their mission.Meanwhile,excessive Zn2+release during degradation will cause in vitro cytotoxicity and in vivo delayed osseointegration.In this review,we firstly summarized the current surface modification methods of Zn-based alloys for the industrial applications.Then we comprehensively summarized the recent progress of biomedical bulk Zn-based BMs as well as the corresponding surface modification strategies.Last but not least,the future perspectives towards the design of surface bio-functionalized coatings on Zn-based BMs for orthopedic and cardiovascular applications were also briefly proposed.
基金the National Natural Science Foundation of China[grant numbers 51901003,51931001,51871004,and 81771039]the National Key R&D Program of China[grant number 2018YFE0104200]+1 种基金the Key Research and Development Program of Ningxia Hui Autonomous Region[grant number 2018BEG02012]the Open Project of NMPA Key laboratory for Dental Materials[grant number PKUSS20200401].
文摘The oral and maxillofacial regions have complex anatomical structures and different tissue types,which have vital health and aesthetic functions.Biodegradable metals(BMs)is a promising bioactive materials to treat oral and maxillofacial diseases.This review summarizes the research status and future research directions of BMs for oral and maxillofacial applications.Mg-based BMs and Zn-based BMs for bone fracture fixation systems,and guided bone regeneration(GBR)membranes,are discussed in detail.Zn-based BMs with a moderate degradation rate and superior mechanical properties for GBR membranes show great potential for clinical translation.Fe-based BMs have a relatively low degradation rate and insoluble degradation products,which greatly limit their application and clinical translation.Furthermore,we proposed potential future research directions for BMs in the oral and maxillofacial regions,including 3D printed BM bone scaffolds,surface modification for BMs GBR membranes,and BMs containing hydrogels for cartilage regeneration,soft tissue regeneration,and nerve regeneration.Taken together,the progress made in the development of BMs in oral and maxillofacial regions has laid a foundation for further clinical translation.
文摘Biodegradable metals are promising candidates for bone defect repair.With an evidence-based approach,this study investigated and analyzed the performance and degradation properties of biodegradable metals in animal models for bone defect repair to explore their potential clinical translation.Animal studies on bone defect repair with biodegradable metals in comparison with other traditional biomaterials were reviewed.Data was carefully collected after identification of population,intervention,comparison,outcome,and study design(PICOS),and following the inclusion criteria of biodegradable metals in animal studies.30 publications on pure Mg,Mg alloys,pure Zn and Zn alloys were finally included after extraction from a collected database of 2543 publications.A qualitative systematic review and a quantitative meta-analysis were performed.Given the heterogeneity in animal model,anatomical site and critical size defect(CSD),biodegradable metals exhibited mixed effects on bone defect repair and degradation in animal studies in comparison with traditional non-degradable metals,biodegradable polymers,bioceramics,and autogenous bone grafts.The results indicated that there were limitations in the experimental design of the included studies,and quality of the evidence presented by the studies was very low.To enhance clinical translation of biodegradable metals,evidence-based research with data validity is needed.Future studies should adopt standardized experimental protocols in investigating the effects of biodegradable metals on bone defect repair with animal models.
基金supported by National Natural Science Foundation of China(No.31670974,No.31370954).
文摘Tracheobronchial obstruction in children due to benign stenosis or tracheobronchomalacia still remains a challenging matter of concern.Currently,there is 10%–20%complication rate in clinical treatment.The nonbiodegradable property of silicone stents and nickel-titanium memory alloy stents take the primary responsibility for drawbacks including stimulating local granulation tissue proliferation,displacement,and stent-related infections.Permanent tracheobronchial stent will be a persistent foreign object for a long time,causing excessive secretion of tracheal mucosa,ulceration and even perforation,which is particularly unsuitable for young children with persistent tracheal growth.In this study,the degradation and biocompatibility performance of three typical biodegradable metals were investigated as potential tracheobronchial stent materials.The results exhibited that these materials showed different degradation behaviors in the simulating respiratory fluid environment compared with SBF.Except for pure iron group,high purity magnesium and zinc showed favorable cell adhesion and proliferation in three culture methodologies(direct culture,indirect culture and extraction culture).The proper corrosion rate and good biocompatibility indicated that high purity magnesium and zinc may be good candidates as tracheobronchial stent materials.
基金supported by the National Natural Science Foundation of China(82027802,82102220,82071468)Beijing Municipal Natural Science Foundation(721220,61975017)General Projects of Scientific and Technological Plan of Beijing Municipal Education Commission(KM202010025023).
文摘Over the past two decades,biodegradable metals(BMs)have emerged as promising materials to fabricate temporary biomedical devices,with the purpose of avoiding potential side effects of permanent implants.In this review,we first surveyed the current status of BMs in neuroscience,and briefly summarized the representative stents for treating vascular stenosis.Then,inspired by the convincing clinical evidence on the in vivo safety of Mg alloys as cardiovascular stents,we analyzed the possibility of producing biodegradable cerebrovascular Mg alloy stents for treating ischemic stroke.For these novel applications,some key factors should also be considered in designing BM brain stents,including the anatomic features of the cerebral vasculature,hemodynamic influences,neuro-cytocompatibility and selection of alloying elements.This work may provide insights into the future design and fabrication of BM neurological devices,especially for brain stents.
基金supported by National Institutes of Health(NIH)grants R01HL144113,R01HL101972,R01HL151367,R01HL168696,and R01HL146549The authors gratefully acknowledge the veterinary staff at the Oregon National Primate Research Center,supported by P51OD011092+1 种基金The authors also appreciate the technical consultations with Dr.Novella Keeling,Dr.Si-Han WangMr.Cole Baker.We thank Mr.Rick Mathews for his assistance in preparing this manuscript.SEM instrumentation was provided with the support of the OHSU Multiscale Microscopy Core.ICP-MS was completed at the OHSU Elemental Analysis Core,which is funded by grant S10OD028492 from the NIH.Schematic images were created with BioRender.com.
文摘Biodegradable metals offer a promising means to ameliorate many of the long-term risks associated with vascular devices made of conventional biostable stent metals.While numerous biodegradable metal alloys have been developed and characterized in animal models,knowledge of their blood reactivity and thrombogenicity remains unknown.Metal hemocompatibility is particularly valuable because current generation drug-eluting stents pose a significant long-term thrombosis risk.In this study,four pure metals,widely used as degradable base materials(Fe,Zn,Mg,and Mo),and three alloys commonly used in cardiovascular devices[NiTi,CoCr,and stainless steel(SS)]were evaluated.This work examined how each of these metals activate platelets,coagulation factors,and inflammation using in vitro hemocompatibility assays and a clinically relevant ex vivo non-human primate arteriovenous shunt model.Testing found that while all metals promoted a downstream activation of platelets and coagulation in flowing whole blood,platelet and fibrin attachment to Mg was markedly reduced.Additionally,Fe and Mo trended toward higher platelet attachment and contact pathway activation.Overall,the results suggest that Mg may delay clot initiation,but not eliminate clot formation,indicating the importance of understanding thrombosis in Mg alloys that are currently being developed for clinical use as biodegradable stents.
基金supported by the National Natural Science Foundation of China(No.5193000081).
文摘Biodegradable metals,designed to be safely degraded and absorbed by the body after fulfil the intended functions,are of particular interest in the 21st century.The marriage of advanced biodegradable metals with clinical needs have yield unprecedented possibility.Magnesium,iron,and zinc-based materials constitute the main components of temporary,implantable metallic medical devices.A burgeoning number of studies on biodegradable metals have driven the clinical translation of biodegradable metallic devices in the fields of cardiology and orthopaedics over the last decade.Their ability to degrade as well as their beneficial biological functions elicited during degradation endow this type of material with the potential to shift the paradigm in the treatment of musculoskeletal and cardiovascular diseases.This review provides an insight into the degradation mechanism of these metallic devices in specific application sites and introduces state-of-the-art translational research in the field of biodegradable metals,as well as highlighting some challenges for materials design strategies in the context of mechanical and biological compatibility.
基金supported by the Science and Technology Planning Project of Guangdong Province(Nos.2024A0505040016 and 2023A0505050148)National Key Research and Development Project of China(2023YFB3809900/2023YFB3809902)Natural Science Foundation of Guangdong Province(No.2025A1515010026)。
文摘Biodegradable metals have garnered considerable interest owing to their capacity for self-degradation following the repair of damaged tissues.This review commences with their historical development and clarifies the essential prerequisites for their successful clinical translation.Subsequently,a detailed review of magnesium-based materials is presented from five critical areas of alloying,fabrication techniques,purification,surface modification,and structural design,systematically addressing their progress in biodegradation rate retardation,mechanical reinforcement,and biocompatibility enhancement.Furthermore,recent breakthroughs in vivo animal experiments and clinical translation of magnesium alloys are summarized.Finally,this review concludes with a critical assessment of the achievements and challenges encountered in the clinical application of these materials,and proposes practical strategies to address current limitations and guide future research perspectives.
基金supported by the National Natural Science Foundation of China under grant No. 51001099
文摘Rare earth （RE） metals are widely used as the alloying implants. However, corrosion behavior of pure RE elements in biodegradable magnesium alloys as medical metals not only in physiological media but also in chlorinated saline environment is not well understood. In the present work, the RE metals Y, Nd, Gd and Dy are selected to investigate their corrosion behavior in 0.1 mol/L NaCI solution with immersion and electrochemistry techniques. As indicated, corrosion of the currently investigated RE metals is promoted in the order of Dy, Y, Gd and Nd. In terms of electrochemical response, such a sequence correlates with the increased impedance and the decreased corrosion rate （CR）. These RE metals manifest weak ability for passivation in the native surface. Then, reaction with aqueous solution easily happens through the anodic dissolution and cathodic hydrogen evolution. The corrosion products, RE（OH）3, adhered on the surface of RE metals, do not have an appreciable power to resist the reaction proceeding with corrosive chloride ions. In contrast to pure Mg, the RE metals, including Y, Nd, Gd and Dy, exhibit significantly fragile corrosion resistance in saline media. Therefore, with the curr correlation of corrosion resistance between RE-contain ent findings, it is impossible to reveal a well-defined ng Mg alloy and RE metal itself
基金supported by National Key R&D Program of China(grant No.2023YFC2410300)National Natural Science Foundation of China(grant No.52130302).
文摘Corrodible metals are the newest kind of biodegradable materials and raise a new problem of the corrosion products.However,the removal of the precipitated products has been unclear and even largely ignored in publications.Herein,we find that albumin,an abundant macromolecule in serum,enhances the solubility of corrosion products of iron in blood mimetic Hank’s solution significantly.This is universal for other main biodegradable metals such as magnesium,zinc and polyester-coated iron.Albumin also influences corrosion rates in diverse trends in Hank’s solution and normal saline.Based on quantitative study theoretically and experimentally,both the effects on corrosion rates and soluble fractions are interpreted by a unified mechanism,and the key factor leading to different corrosion behaviors in corrosion media is the interference of albumin to the Ca/P passivation layer on the metal surface.This work has illustrated that the interactions between metals and media macromolecules should be taken into consideration in the design of the next-generation metal-based biodegradable medical devices in the formulism of precision medicine.The improved Hank’s solution in the presence of albumin and with a higher content of initial calcium salt is suggested to access biodegradable metals potentially for cardiovascular medical devices,where the content of calcium salt is calculated after consideration of chelating of calcium ions by albumin,resulting in the physiological concentration of free calcium ions.
基金National Natural Science Foundation of China(52175274,82172065)Tsinghua Precision Medicine Foundation,Tsinghua-Toyota Joint Research Fund and Cross-Strait Tsinghua Research Institute Fund.
文摘Zinc (Zn)-based biodegradable metals (BMs) fabricated through conventional manufacturing methods exhibit adequate mechanical strength, moderate degradation behavior, acceptable biocompatibility, and bioactive functions. Consequently, they are recognized as a new generation of bioactive metals and show promise in several applications. However, conventional manufacturing processes face formidable limitations for the fabrication of customized implants, such as porous scaffolds for tissue engineering, which are future direction towards precise medicine. As a metal additive manufacturing technology, laser powder bed fusion (L-PBF) has the advantages of design freedom and formation precision by using fine powder particles to reliably fabricate metallic implants with customized structures according to patient-specific needs. The combination of Zn-based BMs and L-PBF has become a prominent research focus in the fields of biomaterials as well as biofabrication. Substantial progresses have been made in this interdisciplinary field recently. This work reviewed the current research status of Zn-based BMs manufactured by L-PBF, covering critical issues including powder particles, structure design, processing optimization, chemical compositions, surface modification, microstructure, mechanical properties, degradation behaviors, biocompatibility, and bioactive functions, and meanwhile clarified the influence mechanism of powder particle composition, structure design, and surface modification on the biodegradable performance of L-PBF Zn-based BM implants. Eventually, it was closed with the future perspectives of L-PBF of Zn-based BMs, putting forward based on state-of-the-art development and practical clinical needs.
基金supported by grants from the National Natural Science Foundation of China(No.52201300)the National Key R&D Program of China(No.2023YFC2416800)+1 种基金China Postdoctoral Science Foundation(No.2021M702090)Changshu Science and Technology Program(Industrial)Project(No.CG202107).
文摘Due to its excellent biocompatibility and biodegradability,Mg has received widespread attention in biomaterials as implants and even biobatteries.However,the poor corrosion resistance makes it difficult to meet the growing demand for implant materials.This study developed a biodegradable nano-heterogeneous Mg(48 wt%)-Zn(52 wt%)-based metal(NHMZ)comprising nanocrystalline matrix phase Mg_(51)Zn_(20) and nanoscale MgZn_(2) precipitates.The unique microstructure of NHMZ enhances its corrosion resistance.The spherical aberration-corrected transmission electron microscope(AC-TEM)and precession electron diffraction(PED)characterized the microstructures.The corrosion rate of NHMZ is about 0.21 mm y^(-1) after soaking for 4 weeks,approximately 58% of high pure Mg.In addition,the anode discharge of NHMZ is more stable than Mg,indicating it has great potential in biological batteries.This work hopes to broaden the development direction of biodegradable metallic materials and break through the performance limitation of current biodegradable Mg alloys.
基金Project(2012CB619102) supported by National Basic Research Program of ChinaProject(31070847) supported by National Natural Science Foundation of China
文摘Extensive in vitro corrosion test systems have been carried out to simulate the in vivo corrosion behavior of biodegradable metallic materials. Various methods have their own unique benefits and limitations. The corrosion mechanism of biodegradable alloys and in vitro corrosion test systems on biodegradable metallic materials are reviewed, to build a reasonable simulated in vitro test system for mimicking the in vivo animal test from the aspects of electrolyte solution selection, surface roughness influence, test methods and evaluation methodology of corrosion rate. Buffered simulated body fluid containing similar components to human blood plasma should be applied as electrolyte solution, such as simulated body fluid （SBF） and culture medium with serum. Surface roughness of samples and ratio of solution volume to sample surface area should be adopted based on the real implant situation, and the dynamic corrosion is preferred. As to the evaluation methodology of corrosion rate, different methods may complement one another.
基金supported financially by the Research Funds of the Wenzhou Science and Technology Bureau (Nos.ZG2019022 and 2018ZG008)support for this research by the Australian Research Council (ARC) through the Discovery Project (No.DP170102557)+1 种基金the Future Fellowship(No.FT160100252)support of the ARC Research Hub for Advanced Manufacturing of Medical Devices (No.IH150100024)。
文摘Zinc(Zn) and its alloys have been proposed as biodegradable implant materials due to their unique combination of biodegradability, biocompatibility, and biofunctionality. However, the insufficient mechanical properties of pure Zn greatly limit its clinical application. Here, we report on the microstructure, mechanical properties, friction and wear behavior, corrosion and degradation properties, hemocompatibility, and cytocompatibility of Zn–3 Cu and Zn–3 Cu–0.2 Ti alloys under three different conditions of as-cast(AC),hot-rolling(HR), and hot-rolling plus cold-rolling(HR + CR). The HR + CR Zn–3 Cu–0.2 Ti exhibited the best set of comprehensive properties among all the alloy samples, with yield strength of 211.0 MPa, ultimate strength of 271.1 MPa, and elongation of 72.1 %. Immersion tests of the Zn–3 Cu and Zn–3 Cu–0.2 Ti alloys in Hanks’ solution for 3 months indicated that the AC samples showed the lowest degradation rate,followed by the HR samples, and then the HR + CR samples, while the HR + CR Zn–3 Cu exhibited the highest degradation rate of 23.9 m/a. Friction and wear testing of the Zn–3 Cu and Zn–3 Cu–0.2 Ti alloys in Hanks’ solution indicated that the AC samples showed the highest wear resistance, followed by the HR samples, and then the HR + CR samples, while the AC Zn–3 Cu–0.2 Ti showed the highest wear resistance.The diluted extracts of HR + CR Zn–3 Cu and Zn–3 Cu–0.2 Ti at a concentration of ≤25 % exhibited noncytotoxicity. Furthermore, both the HR + CR Zn–3 Cu and Zn–3 Cu–0.2 Ti exhibited effective antibacterial properties against S. aureus.
基金supported by the National Natural Science Foundation of China(No.31700819)the Young Elite Scientists Sponsorship Program by CAST(YESS,No.2018QNRC001).
文摘The burst release of Zn 2+from the naked pure Zn and Zn-based alloys could induce local and sys-temic toxicity,which limits their clinical applications as biodegradable implants.In order to inhibit the explosive release of zinc ions,a protective Ca-P coating was synthesized on biodegradable Zn al-loy.The microstructure,corrosion resistance,antibacterial activity,and biosafety of the Ca-P coating are systematically investigated.Electrochemical tests revealed that Ca-P protective layer has enhanced the anti-corrosion behavior of Zn alloy.Furthermore,Ca-P protective layer showed good biocompatibility,as demonstrated by significantly increased cell viability,good attachment,and spreading at a higher cell density.Besides,the Ca-P coating could also retain the antibacterial ability and inhibit the bacterial ad-hesion.The Ca-P protective layer synthesized on biodegradable Zn alloy can be considered and applied in future biomedical applications.
基金supported by the National Natural Science Foundation of China(Nos.51931001 and U22A20121)the Fund for International Cooperation and Exchange between NSFC(China)and CNR(Italy)(NSFC–CNR No.52011530392)the Fund for International Cooperation and Exchange between NSFC(China)and RFBR(Russia)(NSFC-RFBR No.52111530042).
文摘The implants made of metallic biomaterials help healing the bone fracture but also affect the bone repair process.As proposed in Matter 4(2021)2548–2650 by Wang et al.,a precisely adaptable biomaterial ought to recapitulate the targeted tissue with spatiotemporal precision and hierarchical accuracy,ranging from atoms and molecules(genes,proteins,etc.)to cells(including organelles)and to tissues and organs.In comparison to traditional bio-inert metallic bone implants such as Co-based alloys and Ti alloys,biodegradable metal(Mg and Zn alloys)bone implants had been developed and might arise many unexpected variables in the bone repair,due to their bioactive nature.In this paper,the bone repair without and with the presence of metallic implants is compared.Thereafter,the perspectives concerning the interactions between the bone tissues and biodegradable metal implants are put forward,and how to better mimic in vivo biodegradation by in vitro experiments is proposed for further research and development of biodegradable metals.
