Mg-based porous materials,as potential bone tissue engineering scaffolds,are considered an attractive strategy for bone repair owing to favorable biodegradability,good biocompatibility and suitable mechanical properti...Mg-based porous materials,as potential bone tissue engineering scaffolds,are considered an attractive strategy for bone repair owing to favorable biodegradability,good biocompatibility and suitable mechanical properties.In this work,3D-cubic interconnected porous Mg–xZn–0.3Ca(x=0,3,6)scaffolds were prepared to obtain desirable pore structures with a mean porosity up to 73%and main pore size of 400–500μm,which pore structures were close to the human cancellous bone.The structure–property relationships in the present scaffolds were analyzed by experiments and theoretical models of generalized method of cells(GMC).Mg–xZn–0.3Ca scaffolds exhibited good compression properties with a maximum above 5MPa in yield strength and about 0.4GPa in elastic modulus.This was attributed to not only the alloy strengthening but also the large minimum solid area.On the other hand,the scaffolds showed undesirable and relatively serious degradation behavior in Hank’s solution,resulting from Zn addition in Mg-based scaffolds and the high surface area ratio in the pore structure.Therefore,surface modifications are worth studying for controlled degradation in the future.In conclusion,this research would explore a novel attempt to introduce 3D-cubic pore structure for Mg-based scaffolds,and provide new insights into the preparations of Mg-based scaffolds with good service performances for bone repair.展开更多
Cerium-based sealing treatment was developed for Mg-Al hydrotalcite film on AZ91D Mg alloy,and the influence of cerium salt solution was investigated to modify the surface integrity and corrosion resistance.Scanning e...Cerium-based sealing treatment was developed for Mg-Al hydrotalcite film on AZ91D Mg alloy,and the influence of cerium salt solution was investigated to modify the surface integrity and corrosion resistance.Scanning electron microscope(SEM)and X-ray diffraction(XRD)measurements were carried out to analyze the surface morphology and phase composition.The corrosion resistance of Mg-Al hydrotalcite film after sealing treatment was evaluated by the polarization curve and electrochemical impedance spectroscopy(EIS)tests.The results showed that lower concentration of Ce-containing solution was beneficial to seal the micro-cracks on Mg-Al hydrotalcite film,and improve the surface integrity and corrosion resistance;higher concentration of Ce-containing solution could seal fewer micro-cracks,and the corrosion resistance was decreased owing to the disintegration of Mg-Al hydrotalcite film.展开更多
Self-healing coatings have been developed as smart surface coatings for Mg and its alloys to retain local corrosion from the coating damages.In this study,we prepared dicalcium phosphate dihydrate(DCPD)coating on biom...Self-healing coatings have been developed as smart surface coatings for Mg and its alloys to retain local corrosion from the coating damages.In this study,we prepared dicalcium phosphate dihydrate(DCPD)coating on biomedical Mg,and found that the artificial scratches in DCPD coating can be efficiently sealed by anti-corrosive products in both Hank's and normal saline(NS)solutions.Besides,the in-depth study revealed that DCPD was served as not only a physical barrier but also a self-healing agent,demonstrating an autonomous self-healing coating without embedded extra corrosion inhibitors.Moreover,Hank's solution provided foreign-aid filmforming ions to promote self-healing behavior.The findings might offer new opportunities for further studies and applications of efficient self-healing coatings on biodegradable Mg implants.展开更多
基金This work was supported by the National Key Research and Development Program of China(No.2016YFC1102402)the National Natural Science Foundation of China(No.51771054,No.51971062)+1 种基金the Science and Technology Project of Jiangsu Province(No.BE2019679)the Fundamental Research Funds for the Central Universities(No.2242018K3DN03,No.2242019K40057).
文摘Mg-based porous materials,as potential bone tissue engineering scaffolds,are considered an attractive strategy for bone repair owing to favorable biodegradability,good biocompatibility and suitable mechanical properties.In this work,3D-cubic interconnected porous Mg–xZn–0.3Ca(x=0,3,6)scaffolds were prepared to obtain desirable pore structures with a mean porosity up to 73%and main pore size of 400–500μm,which pore structures were close to the human cancellous bone.The structure–property relationships in the present scaffolds were analyzed by experiments and theoretical models of generalized method of cells(GMC).Mg–xZn–0.3Ca scaffolds exhibited good compression properties with a maximum above 5MPa in yield strength and about 0.4GPa in elastic modulus.This was attributed to not only the alloy strengthening but also the large minimum solid area.On the other hand,the scaffolds showed undesirable and relatively serious degradation behavior in Hank’s solution,resulting from Zn addition in Mg-based scaffolds and the high surface area ratio in the pore structure.Therefore,surface modifications are worth studying for controlled degradation in the future.In conclusion,this research would explore a novel attempt to introduce 3D-cubic pore structure for Mg-based scaffolds,and provide new insights into the preparations of Mg-based scaffolds with good service performances for bone repair.
基金supported by the National Natural Science Foundation of China(No.51701093)the Natural Science Foundation of Jiangsu Province(No.BK20170764)+2 种基金the Six Talent Peaks(No.2015-XCL-025)the Qing Lan Project of Jiangsu Province,the Practice Innovation Program for graduate students of Jiangsu Province(No.SJZZ16_0292)the Research Fund of Nanjing Institute of Technology(No.JCYJ201603).
文摘Cerium-based sealing treatment was developed for Mg-Al hydrotalcite film on AZ91D Mg alloy,and the influence of cerium salt solution was investigated to modify the surface integrity and corrosion resistance.Scanning electron microscope(SEM)and X-ray diffraction(XRD)measurements were carried out to analyze the surface morphology and phase composition.The corrosion resistance of Mg-Al hydrotalcite film after sealing treatment was evaluated by the polarization curve and electrochemical impedance spectroscopy(EIS)tests.The results showed that lower concentration of Ce-containing solution was beneficial to seal the micro-cracks on Mg-Al hydrotalcite film,and improve the surface integrity and corrosion resistance;higher concentration of Ce-containing solution could seal fewer micro-cracks,and the corrosion resistance was decreased owing to the disintegration of Mg-Al hydrotalcite film.
基金the National Key Research and Development Program of China(No.2016YFC1102402)the National Natural Science Foundation of China(No.51771054,No.51971062)+2 种基金the Science and Technology Project of Jiangsu Province(No.BE2019679)the Fundamental Research Funds for the Central Universities(No.2242018K3DN03,No.2242020K40003)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX20_0089).
文摘Self-healing coatings have been developed as smart surface coatings for Mg and its alloys to retain local corrosion from the coating damages.In this study,we prepared dicalcium phosphate dihydrate(DCPD)coating on biomedical Mg,and found that the artificial scratches in DCPD coating can be efficiently sealed by anti-corrosive products in both Hank's and normal saline(NS)solutions.Besides,the in-depth study revealed that DCPD was served as not only a physical barrier but also a self-healing agent,demonstrating an autonomous self-healing coating without embedded extra corrosion inhibitors.Moreover,Hank's solution provided foreign-aid filmforming ions to promote self-healing behavior.The findings might offer new opportunities for further studies and applications of efficient self-healing coatings on biodegradable Mg implants.