Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering application.The present study deals with further improvement in the tensile strength and biological properties of...Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering application.The present study deals with further improvement in the tensile strength and biological properties of this type of scaffold to make it a potential template for bone-tissue regeneration.We experimented with adding 0%–15%(volume fraction)gelatin(GE),a protein-based biopolymer known to promote cell adhesion,proliferation,and differentiation.The resulting tri-polymer complex was used as bioink to fabricate SA/CH/GEmatrices by three-dimensional(3D)printing.Morphological studies using scanning electron microscopy revealed the microfibrous porous architecture of all the structures,which had a pore size range of 383–419μm.X-ray diffraction and Fourier-transform infrared spectroscopy analyses revealed the amorphous nature of the scaffold and the strong electrostatic interactions among the functional groups of the polymers,thereby forming polyelectrolyte complexes which were found to improve mechanical properties and structural stability.The scaffolds exhibited a desirable degradation rate,controlled swelling,and hydrophilic characteristics which are favorable for bone-tissue engineering.The tensile strength improved from(386±15)to(693±15)kPa due to the increased stiffness of SA/CH scaffolds upon addition of gelatin.The enhanced protein adsorption and in vitro bioactivity(forming an apatite layer)confirmed the ability of the SA/CH/GE scaffold to offer higher cellular adhesion and a bone-like environment to cells during the process of tissue regeneration.In vitro biological evaluation including the MTT assay,confocal microscopy analysis,and alizarin red S assay showed a significant increase in cell attachment,cell viability,and cell proliferation,which further improved biomineralization over the scaffold surface.In addition,SA/CH containing 15%gelatin designated as SA/CH/GE15 showed superior performance to the other fabricated 3D structures,demonstrating its potential for use in bone-tissue engineering.展开更多
用硅烷和钛酸酯偶联剂对 Ba Ti O3粉进行了表面处理 ,使用溶剂法制备了 PVDF/Ba Ti O3复合薄膜。通过疏水亲油实验定性地分析了硅烷和钛酸酯偶联剂对 Ba Ti O3粉的偶联作用可以改善 PVDF/Ba-Ti O3的界面结合 ,通过测定 PVDF/Ba Ti O3的...用硅烷和钛酸酯偶联剂对 Ba Ti O3粉进行了表面处理 ,使用溶剂法制备了 PVDF/Ba Ti O3复合薄膜。通过疏水亲油实验定性地分析了硅烷和钛酸酯偶联剂对 Ba Ti O3粉的偶联作用可以改善 PVDF/Ba-Ti O3的界面结合 ,通过测定 PVDF/Ba Ti O3的介电常数和介电损耗角正切值表征了复合材料的介电性能 ,PVDF/Ba Ti O3扫描电子显微镜 (SEM)的微观形态分析发现 ,经过偶联剂表面处理 ,Ba Ti O3粉在PVDF中的分散情况改善 。展开更多
研究了在 Ba Ti O3水浆料中通过加入丙烯酰胺有机单体原位聚合形成聚丙烯酰胺的过程制备厚膜。生坯的柔韧性通过加入丙三醇作为增塑剂加以改善。实验结果表明 ,由于所制备浆料的均匀性好 ,这种由原位聚合形成的厚膜显微结构均匀 ,电性...研究了在 Ba Ti O3水浆料中通过加入丙烯酰胺有机单体原位聚合形成聚丙烯酰胺的过程制备厚膜。生坯的柔韧性通过加入丙三醇作为增塑剂加以改善。实验结果表明 ,由于所制备浆料的均匀性好 ,这种由原位聚合形成的厚膜显微结构均匀 ,电性能优良。展开更多
BaTiO 3 ceramics doped with Nd 2 O 3 (the additive content was respectively 0.001,0.002,0.003,0.005,0.01,0.03mol)were prepared by Sol-Gel method.Effects of Nd 2 O 3 contents on the dielectric constant (ε),the dielect...BaTiO 3 ceramics doped with Nd 2 O 3 (the additive content was respectively 0.001,0.002,0.003,0.005,0.01,0.03mol)were prepared by Sol-Gel method.Effects of Nd 2 O 3 contents on the dielectric constant (ε),the dielectric loss(tanδ),the Curie-temperature(T C )and the resistivity(ρ)of BaTiO 3 ceramic were studied.When Nd 2 O 3 content was 0.001mol and 0.002mol,t he dielectric constant was increase d obviously,but the dielectric loss was also increased.When Nd 2 O 3 content was 0.003mol,the dielectric constant was increased,and the die lectric loss was decreased,which was suitable fo r application in condenser.The resistivity was decreased obviously with the increasing of Nd 2 O 3 contents,the resistivity was the sm allest when Nd 2 O 3 content was 0.001mol.The Curie-temperature was also decreased with the increasing of Nd 2 O 3 contents.展开更多
基金The authors are thankful to Ministry of Human Resource Development(presently Ministry of Education),Government of India,New Delhi,for providing research facility by sanctioning Center of Excellence(F.No.5-6/2013-TS VII)in Tissue Engineering and Center of Excellence in Orthopedic Tissue Engineering and Rehabilitation funded by World Bank under TEQIP-II.
文摘Sodium alginate(SA)/chitosan(CH)polyelectrolyte scaffold is a suitable substrate for tissue-engineering application.The present study deals with further improvement in the tensile strength and biological properties of this type of scaffold to make it a potential template for bone-tissue regeneration.We experimented with adding 0%–15%(volume fraction)gelatin(GE),a protein-based biopolymer known to promote cell adhesion,proliferation,and differentiation.The resulting tri-polymer complex was used as bioink to fabricate SA/CH/GEmatrices by three-dimensional(3D)printing.Morphological studies using scanning electron microscopy revealed the microfibrous porous architecture of all the structures,which had a pore size range of 383–419μm.X-ray diffraction and Fourier-transform infrared spectroscopy analyses revealed the amorphous nature of the scaffold and the strong electrostatic interactions among the functional groups of the polymers,thereby forming polyelectrolyte complexes which were found to improve mechanical properties and structural stability.The scaffolds exhibited a desirable degradation rate,controlled swelling,and hydrophilic characteristics which are favorable for bone-tissue engineering.The tensile strength improved from(386±15)to(693±15)kPa due to the increased stiffness of SA/CH scaffolds upon addition of gelatin.The enhanced protein adsorption and in vitro bioactivity(forming an apatite layer)confirmed the ability of the SA/CH/GE scaffold to offer higher cellular adhesion and a bone-like environment to cells during the process of tissue regeneration.In vitro biological evaluation including the MTT assay,confocal microscopy analysis,and alizarin red S assay showed a significant increase in cell attachment,cell viability,and cell proliferation,which further improved biomineralization over the scaffold surface.In addition,SA/CH containing 15%gelatin designated as SA/CH/GE15 showed superior performance to the other fabricated 3D structures,demonstrating its potential for use in bone-tissue engineering.
文摘用硅烷和钛酸酯偶联剂对 Ba Ti O3粉进行了表面处理 ,使用溶剂法制备了 PVDF/Ba Ti O3复合薄膜。通过疏水亲油实验定性地分析了硅烷和钛酸酯偶联剂对 Ba Ti O3粉的偶联作用可以改善 PVDF/Ba-Ti O3的界面结合 ,通过测定 PVDF/Ba Ti O3的介电常数和介电损耗角正切值表征了复合材料的介电性能 ,PVDF/Ba Ti O3扫描电子显微镜 (SEM)的微观形态分析发现 ,经过偶联剂表面处理 ,Ba Ti O3粉在PVDF中的分散情况改善 。
文摘BaTiO 3 ceramics doped with Nd 2 O 3 (the additive content was respectively 0.001,0.002,0.003,0.005,0.01,0.03mol)were prepared by Sol-Gel method.Effects of Nd 2 O 3 contents on the dielectric constant (ε),the dielectric loss(tanδ),the Curie-temperature(T C )and the resistivity(ρ)of BaTiO 3 ceramic were studied.When Nd 2 O 3 content was 0.001mol and 0.002mol,t he dielectric constant was increase d obviously,but the dielectric loss was also increased.When Nd 2 O 3 content was 0.003mol,the dielectric constant was increased,and the die lectric loss was decreased,which was suitable fo r application in condenser.The resistivity was decreased obviously with the increasing of Nd 2 O 3 contents,the resistivity was the sm allest when Nd 2 O 3 content was 0.001mol.The Curie-temperature was also decreased with the increasing of Nd 2 O 3 contents.
