The mechanical properties and water solubility of electrospinning SF films limit their use as biomaterials. In order to develop a tissue engineering biomaterial with both satisfying biological properties and sufficien...The mechanical properties and water solubility of electrospinning SF films limit their use as biomaterials. In order to develop a tissue engineering biomaterial with both satisfying biological properties and sufficient biomechanical properties,blended films composed of silk fibroin( SF) and poly( ε-caprolactone)( PCL) were fabricated by electrospinning in this study. Scanning electron microscope( SEM), X-ray diffraction( XRD),thermal analysis,Fourier transform-infrared( FT-IR),Raman spectra,mechanical testing,and water solubility were used to characterize the morphological, structural and mechanical properties of the blended electrospinning films. Results showed that the diameter of the blended fiber was distributed between 600 and1000 nm,and the fiber diameter increased as the PCL content increased. There is no obvious phase separation due to the similarity and intermiscibility,as well as the interactions( mainly hydrogen bonds), between the two polymers. Meanwhile, the secondary structures of SF changed from random coils and Silk I to Silk II because of the interactions between SF and PCL. For this reason,the tensile strength and elongation at break of the electrospinning films improved significantly,and the water solubility decreased. In conclusion,the blended electrospinning films fabricated in this study showed satisfying mechanical properties and water insolubilities,and they may be promising biomaterials for applications in tissue engineering for blood vessels,nerve conduits,tendons,ligaments and other tissues.展开更多
Macrophages are known to modulate the osteogenic environment of bone regeneration elicited by biological bone grafts.Alteration in certain chemical components tends to affect macrophages polarization.Comparatively to ...Macrophages are known to modulate the osteogenic environment of bone regeneration elicited by biological bone grafts.Alteration in certain chemical components tends to affect macrophages polarization.Comparatively to hydroxyapatite(HAp),carbonate hydroxyapatite(CHA)consists of 7.4(wt%)carbonate ions and more closely resembles the mineral content of bone.It remains unknown whether CHA scaffolds or HA scaffolds have better osteogenic properties.In this study,we fabricated PCL/SF scaffold,PCL/SF/HAp scaffold and PCL/SF/CHA scaffold using the electrospinning technique.Despite comparable mechanical properties,the PCL/SF/CHA scaffold exhibited better osteogenic properties than the PCL/SF/HAp scaffold.Although no significant differences were observed between the two scaffolds for promoting osteoblast differentiation in vitro,the PCL/SF/CHA group appeared to be more effective at promoting bone regeneration in cranial defects in vivo.The PCL/SF/CHA scaffold was found to promote macrophage polarization toward M2 via activating the JAK/STAT5 pathway which caused a pro-osteogenic microenvironment to facilitate osteoblast differentiation.The results of this study indicated a higher potential of CHA to substitute HAp in the production of bone scaffolds for better bone regeneration.展开更多
基金National Natural Science Foundations of China(No.30970714,No.51103092)Natural Science Foundation of Jiangsu Province,China(No.BK2012634)+1 种基金College Natural Science Research Project of Jiangsu Province,China(No.12KJA430003)Priority Academic Program Development of Jiangsu Higher Education Institutions,China
文摘The mechanical properties and water solubility of electrospinning SF films limit their use as biomaterials. In order to develop a tissue engineering biomaterial with both satisfying biological properties and sufficient biomechanical properties,blended films composed of silk fibroin( SF) and poly( ε-caprolactone)( PCL) were fabricated by electrospinning in this study. Scanning electron microscope( SEM), X-ray diffraction( XRD),thermal analysis,Fourier transform-infrared( FT-IR),Raman spectra,mechanical testing,and water solubility were used to characterize the morphological, structural and mechanical properties of the blended electrospinning films. Results showed that the diameter of the blended fiber was distributed between 600 and1000 nm,and the fiber diameter increased as the PCL content increased. There is no obvious phase separation due to the similarity and intermiscibility,as well as the interactions( mainly hydrogen bonds), between the two polymers. Meanwhile, the secondary structures of SF changed from random coils and Silk I to Silk II because of the interactions between SF and PCL. For this reason,the tensile strength and elongation at break of the electrospinning films improved significantly,and the water solubility decreased. In conclusion,the blended electrospinning films fabricated in this study showed satisfying mechanical properties and water insolubilities,and they may be promising biomaterials for applications in tissue engineering for blood vessels,nerve conduits,tendons,ligaments and other tissues.
基金supported by funds from the National Natural Science Foundation of China(82071156 to K.Z.,81901025 to X.J.)from the Guangdong Basic and Applied Basic Research Foundation(2019A1515011326 to X.J.)by the Fundamental Research Funds for the Central Universities(19ykpy82 to X.J.).
文摘Macrophages are known to modulate the osteogenic environment of bone regeneration elicited by biological bone grafts.Alteration in certain chemical components tends to affect macrophages polarization.Comparatively to hydroxyapatite(HAp),carbonate hydroxyapatite(CHA)consists of 7.4(wt%)carbonate ions and more closely resembles the mineral content of bone.It remains unknown whether CHA scaffolds or HA scaffolds have better osteogenic properties.In this study,we fabricated PCL/SF scaffold,PCL/SF/HAp scaffold and PCL/SF/CHA scaffold using the electrospinning technique.Despite comparable mechanical properties,the PCL/SF/CHA scaffold exhibited better osteogenic properties than the PCL/SF/HAp scaffold.Although no significant differences were observed between the two scaffolds for promoting osteoblast differentiation in vitro,the PCL/SF/CHA group appeared to be more effective at promoting bone regeneration in cranial defects in vivo.The PCL/SF/CHA scaffold was found to promote macrophage polarization toward M2 via activating the JAK/STAT5 pathway which caused a pro-osteogenic microenvironment to facilitate osteoblast differentiation.The results of this study indicated a higher potential of CHA to substitute HAp in the production of bone scaffolds for better bone regeneration.
