A novel antibacterial biomimetic porous titanium implant with good osseointegration was prepared by freeze-casting and thermal oxidation.Bone integration properties of the porous titanium implant were evaluated by cel...A novel antibacterial biomimetic porous titanium implant with good osseointegration was prepared by freeze-casting and thermal oxidation.Bone integration properties of the porous titanium implant were evaluated by cell proliferation assay,alkaline phosphatase activity assay,X-ray examination and hard bone tissue biopsy.The in vitro cell proliferation and the level of differentiation of the group with a modified nano-porous implant surface were significantly higher than those in the group without surface modification and the dense titanium control group(P<0.05).In vivo,bone growth and osteogenesis were found in the experimental groups with modified and unmodified porous titanium implants;osteoblasts in the modified group had more mature differentiation in the pores compared to the unmodified group.Such implants can form solid,biologically compatible bone grafts with bone tissues,exhibiting good osseointegration.展开更多
In this work FePt-Au heterostructured nanocrystals (HNCs) such as tadpole-, dumbbell-, bead-, and necklace-like nanostructures were synthesized by a facile heteroepitaxial growth of Au NCs onto FePt nanorods (NRs)...In this work FePt-Au heterostructured nanocrystals (HNCs) such as tadpole-, dumbbell-, bead-, and necklace-like nanostructures were synthesized by a facile heteroepitaxial growth of Au NCs onto FePt nanorods (NRs). A study of the growth mechanism revealed that the morphology control of the final products can be correlated with the adsorption sites of hydrogen onto the FePt NRs, which can be manipulated by the amount of the forming gas (At/7% H2) added. Not only the optical characteristic and magnetic properties of the intrinsic materials were retained in the products, but also the FePt-Au HNCs showed the tunable multifunctional properties resulted from the interactions between Au and FePt. Moreover, for methanol oxidation, the FePt-Au HNCs exhibited enhanced catalytic activity and CO tolerance on the catalyst surface compared to commercial Pt catalysts. It is worth noting that as multifunctional units, the FePt-Au HNCs also possess a heterogeneous surface, which could potentially enable their site-specific functionalization for targeting or imaging purposes in biomedical applications. More interestingly, the catalytic properties of the FePt-Au HNCs also endow this material with application potentials in nanocatalysis.展开更多
基金Projects (51290295,51305464) supported by the National Natural Science Foundation of ChinaProject (2016JJ6156) supported by the Natural Science Foundation of Hunan Province,China+1 种基金Project (2016JC2064) supported by Key Research and Development Project of Hunan Province,ChinaProject (20130162120094) supported by Specialized Research Fund for the Doctoral Program of Higher Education,China
文摘A novel antibacterial biomimetic porous titanium implant with good osseointegration was prepared by freeze-casting and thermal oxidation.Bone integration properties of the porous titanium implant were evaluated by cell proliferation assay,alkaline phosphatase activity assay,X-ray examination and hard bone tissue biopsy.The in vitro cell proliferation and the level of differentiation of the group with a modified nano-porous implant surface were significantly higher than those in the group without surface modification and the dense titanium control group(P<0.05).In vivo,bone growth and osteogenesis were found in the experimental groups with modified and unmodified porous titanium implants;osteoblasts in the modified group had more mature differentiation in the pores compared to the unmodified group.Such implants can form solid,biologically compatible bone grafts with bone tissues,exhibiting good osseointegration.
基金This work was supported in part by National Natural Science Foundation of China (NSFC) (Nos. 90922033 and 20941003), the National Basic Research Program of China (No. 2010CB934601), the Doctoral Program (No. 20090001120010), and New Century Talents of the Education Ministry of China (No. NCET-09-0177), the Yok Ying Tung Foundation (No. 122043), the Beijing Outstanding Talent Program (No. 2009D013001000013), and New Star Program of Beijing Committee of Science and Technology (BCST) (No. 2008B02).
文摘In this work FePt-Au heterostructured nanocrystals (HNCs) such as tadpole-, dumbbell-, bead-, and necklace-like nanostructures were synthesized by a facile heteroepitaxial growth of Au NCs onto FePt nanorods (NRs). A study of the growth mechanism revealed that the morphology control of the final products can be correlated with the adsorption sites of hydrogen onto the FePt NRs, which can be manipulated by the amount of the forming gas (At/7% H2) added. Not only the optical characteristic and magnetic properties of the intrinsic materials were retained in the products, but also the FePt-Au HNCs showed the tunable multifunctional properties resulted from the interactions between Au and FePt. Moreover, for methanol oxidation, the FePt-Au HNCs exhibited enhanced catalytic activity and CO tolerance on the catalyst surface compared to commercial Pt catalysts. It is worth noting that as multifunctional units, the FePt-Au HNCs also possess a heterogeneous surface, which could potentially enable their site-specific functionalization for targeting or imaging purposes in biomedical applications. More interestingly, the catalytic properties of the FePt-Au HNCs also endow this material with application potentials in nanocatalysis.