羟基磷灰石/丝素蛋白复合材料的制备

以蚕丝丝素蛋白(SF)作为羟基磷灰石(HA)沉积的模板,制备HA/SF复合粉末,用扫描电镜(SEM)、热重分析(TGA)、X射线衍射(XRD)和傅立叶变换红外光谱(FT-IR)对复合粉末进行分析和鉴定。结果表明,合成产物是HA/SF复合物,其平均粒径约为275.7 nm,其中丝素蛋白含量为17.8%(质量分数)。复合粉末经等静压成型后能够制得弯曲和压缩强度分别为19.87 M Pa和28.65 M Pa的HA/SF复合材料,以N aC l为致孔剂能够制得平均孔径约为61μm、孔隙率为40%的多孔HA/SF复合材料。     

高强度力学性能丝素/羟基磷灰石多孔支架材料的初步制备

以丝素和羟基磷灰石为基材,磷酸盐缓冲液为溶剂,戊二醛为交联剂制备丝素/羟基磷灰石支架材料,对丝素生物材料在骨材料中的开发应用有积极意义。研究表明,丝素/羟基磷灰石复合材料具有结晶结构和β构象。当丝素与羟基磷灰石的比例为6/4时,支架材料的弹性模量和压缩强度达到最大,分别为48.087 MPa和1.427 MPa,孔隙率...     

纳米羟基磷灰石／丝素蛋白多孔支架材料的制备和表征

采用硝酸钙-丝素蛋白溶液与磷酸钠反应仿生合成纳米羟基磷灰石/丝素蛋白(n-HA/SF)复合材料,并以NaHCO3和NaCl为致孔剂制备了多孔复合支架材料,采用TEM、IR、SEM和EDX对其进行了表征.结果表明,复合材料中HA的粒径在20～50nm之间,是一种CO2-3部分替代型弱结晶类骨针晶,在形貌和尺寸等方面类似于人体骨磷灰石晶体;HA和SF两相间存在强烈的键合作用,复合支架材料呈高度多孔结构,孔壁上富含微孔,孔隙间贯通性高.EDX分析结果表明,HA在有机基体中分布均匀,钙磷元素比为1.66,当复合材料和致孔剂的比例为1:0.5时,其抗压强度可达20.23MPa.     

"一步法"制备纳米相丝素蛋白/羟基磷灰石生物复合材料

系统分析了羟基磷灰石(HA)的制备方法和丝素蛋白纤维(SF)的溶解方法,提出一种制备纳米丝素蛋白/羟基磷灰石生物复合材料(SF/HA)的新型反应复合方法--"一步法".并对由"一步法"制得的SF/HA分别进行了钙磷比测定、红外光谱测试、透射电镜观察和x射线衍射测试.结果表明:SF/HA中的钙磷比是1.6692,与标准HA中的钙磷比1.67一致;SF/HA中同时含有SF和HA中各自的官能团;SF/HA的晶粒横向尺度小于100nm,SF/HA呈针状或柱状晶粒,SF和HA能够形成复合;SF/HA的晶型属于六方晶系,当SF在SF/HA中所占质量分数为10%时,晶胞参数a=b=9.0319(A),c=7.0148(A),沿c轴方向平均品粒尺寸是230.7645(A)."一步法"制备SF/HA具有合理性和可行性.     

丝素蛋白/羟基磷灰石复合材料的制备及性能表征

为了改善羟基磷灰石( HAP) 的脆性和新骨诱导性, 采用共沉淀法合成HAP , 盐溶法制备丝素蛋白(SF) , 在胶体状态下将HAP 和SF 复合得到了SF/ HAP 复合材料。采用扫描电镜(SEM) 、X 射线衍射(XRD) ,傅立叶红外光谱( FIR) 对复合材料结构和化学组成进行了分析, 在模拟体液中检验了复合材料的生物活性, 并对其抗压强度进行了测定。结果表明: HAP 与SF 在纳米尺度进行了复合, 复合材料中SF 主要以β-折叠构象存在,酰胺Ⅴ红外特征峰消失,β-折叠构象的其他峰发生了移动, 表明HAP 与SF 间存在化学结合; 模拟体液中浸泡18 天后, 复合材料表面形成了片层状的HAP ; 与纯的HAP 晶体比较, 复合材料结构稳定, 具有较好生物活性和骨诱导性, 其抗压强度可达63 MPa , 可望成为理想的骨组织替换和工程支架材料。      

“一步法”制备纳米相丝素蛋白/羟基磷灰石生物复合材料

系统分析了羟基磷灰石（HA）的制备方法和丝素蛋白纤维（SF）的溶解方法,提出一种制备纳米丝素蛋白/羟基磷灰石生物复合材料（SF/HA）的新型反应复合方法——“一步法”。并对由“一步法”制得的SF/HA分别进行了钙磷比测定、红外光谱测试、透射电镜观察和X射线衍射测试。结果表明：SF/HA中的钙磷比是1.6692,与标准HA中的钙磷比1.67一致;SF/HA中同时含有SF和HA中各自的官能团;SF/HA的晶粒横向尺度小于100 nm,SF/HA呈针状或柱状晶粒, SF和HA能够形成复合; SF/HA的晶型属于六方晶系, 当SF在SF/HA中所占质量分数为10%时,晶胞参数a=b=9.0319 A,c=7.0148 A,沿c轴方向平均晶粒尺寸是230.7645 A。“一步法”制备SF/HA具有合理性和可行性。     

丝素/细菌纤维素/羟基磷灰石骨仿生支架的制备及性能研究

将丝素蛋白(SF)、细菌纤维素纳米纤维束(BCNR)和不同比例的纳米羟基磷灰石(nHAp)搅拌混合均匀,通过冷冻干燥法制备骨仿生支架.利用SEM、FTIR、电子万能材料试验机等设备对复合支架的结构和性能进行表征,选用骨髓间充质干细胞和CCK-8试剂表征细胞在典型支架材料上的黏附和扩增水平.结果表明,骨活性成份nHAp的...     

壳聚糖修饰纳米羟基磷灰石/聚酰胺复合多孔支架的制备及性能研究

利用相转移法制备了纳米羟基磷灰石/聚酰胺66(n-HA/PA66)复合多孔支架.用不同浓度(1%、3%、5%)的壳聚糖(CS)溶液对多孔支架进行了表面修饰.用扫描电镜(SEM)和材料力学试验机对多孔支架修饰前后的形貌和力学性能进行了表征.研究了经CS修饰的n-HA/PA66复合多孔支架在磷酸盐缓冲溶液(PBS)中的浸泡行为,并初步研究了其与MG63细胞的细胞相客性.结果显示,多孔支架具有较为理想的孔隙结构和贯通性,经CS修饰后,其力学强度有显著提高.体外浸泡结果显示,随着漫泡时间的增加,支架表面微结构变得粗糙和多孔化.细胞实验表明该支架有利于细胞在表面的粘附、铺展、生长和增殖.     

纳米羟基磷灰石／丝素蛋白生物复合材料的制备和表征

采用硝酸钙-丝素蛋白溶液与磷酸钠原位合成纳米羟基磷灰石(HA),在反应过程中丝蛋白(SF)诱导HA晶体生长,仿生合成HA/SF复合材料,用TEM、IR、TGA、XRD和SEM进行表征。结果表明,HA为CO23-部分替代型,粒径为10 nm~40 nm之间的弱结晶类骨晶体,在形貌和结晶度等方面与人体骨磷灰石相似。HA/SF复合材料中丝蛋白的含量约为25%,HA和SF两相存在强烈化学键合作用。SEM观察结果表明,HA微粒被SF完全包裹,两者之间没有明显相分离。     

纳米羟基磷灰石/丝素蛋白/聚己内酯复合超细纤维的制备及表征

通过静电纺丝法制备出纳米羟基磷灰石/丝素蛋白/聚己内酯复合超细纤维,利用扫描电镜、红外光谱仪、X射线衍射仪对纳米羟基磷灰石/丝素蛋白/聚己内酯复合超细纤维形貌和结构进行表征,并进行了拉伸测试。结果表明,随着超细纤维中羟基磷灰石含量的增加,纤维的直径逐渐降低,纤维中聚己内酯的结晶逐渐变差。相比于丝素蛋白/聚己内酯超细纤维,含有质量比为30%羟基磷灰石的复合超细纤维仍具有较好的力学性能。体外小鼠成纤维细胞(L929)培养表明,纳米羟基磷灰石/丝素蛋白/聚己内酯复合超细纤维对细胞没有毒性。     

Micro-patterned hydroxyapatite/silk fibroin coatings on Mg--Zn--Y--Nd--Zr alloys for better corrosion resistance and cell behavior guidance

In this study, a micro-patterned hydroxyapatite/silk fibroin (HA-SF) coating was firstly fabricated on the surface of Mg–Zn–Y–Nd–Zr alloy by template-assisted electrospraying technique coupling with spin coating technique. Two types of micro-patterns were achieved with high contour accuracy, namely HA-SF(line-pattern) and HA-SF(dot-pattern). The microstructure, composition, surface wettability and corrosion behaviors of the coatings were investigated by SEM, EDS, FTIR, XRD, water contact angle and potentiodynamic polarization test. The results revealed the hydrophilic nature of coatings and two orders of magnitude reduction of corrosion density (i_corr) as compared with that of the substrate. All the micro-patterned surfaces promoted the attachment of MC3T3-E1 cells with visible filopodia after 1 d incubation. In addition, coatings with line pattern exhibited the superior guidance to cell migration as compared to dot pattern, and the preference of cell attachment in the convex zone was observed. In summary, the obtained micro-patterned HA-SF coatings possessed the remarkably improvement of anticorrosion ability and good efficacy in guidance of cell attachment and alignment, which can serve as a promising strategy for cellular response modulation at the interface of magnesium-based implants and bone.     

Preparation and cytocompatibility of silk fibroin/chitosan scaffolds

One challenge in soft tissue engineering is to find an applicable scaffold, not only having suitable mechanical properties, porous structures, and biodegradable properties, but also being abundant in active groups and having good biocompatibility. In this study, a three-dimensional silk fibroin/chitosan (SFCS) scaffold was successfully prepared with interconnected porous structure, excellent hydrophilicity, and proper mechanical properties. Compared with polylactic glycolic acid (PLGA) scaffold, the SFCS scaffold further facilitated the growth of HepG2 cells (human hepatoma cell line). Keeping the good cytocompatibility and combining the advantages of both fibroin and chitosan, the SFCS scaffold should be a prominent candidate for soft tissue engineering, for example, liver.     

Preparation and cytocompatibility of silk fibroin / chitosan scaffolds

One challenge in soft tissue engineering is to find an applicable scaffold, not only having suitable mechanical properties, porous structures, and biodegradable properties, but also being abundant in active groups and having good biocompatibility. In this study, a three-dimensional silk fibroin/chitosan (SFCS) scaffold was successfully prepared with interconnected porous structure, excellent hydrophilicity, and proper mechanical properties. Compared with polylactic glycolic acid (PLGA) scaffold, the SFCS scaffold further facilitated the growth of HepG2 cells (human hepatoma cell line). Keeping the good cytocompatibility and combining the advantages of both fibroin and chitosan, the SFCS scaffold should be a prominent candidate for soft tissue engineering, for example, liver.     

纳米TiO2改性丝素性能及整理织物染色性能的研究

利用超声分散原理,将Ti(OC4H9)4/乙醇加入到丝素溶液中,发生水解-缩聚反应,制得纳米TiO2再生丝素膜.对膜的溶失率和机械强度测试,续对之进行SEM、XRD、FTIR、EDS及复合丝素整理织物的染色性能的表征.结果表明,纳米粒子在丝素膜中分布均匀,随着纳米TiO2的加入,膜机械强度提高,在水中溶失率下降;丝素膜的结晶结构从Silk Ⅰ向Silk Ⅱ转化,用复合丝素整理织物的上染率和色牢度均比纯丝素整理的高.     

甲醇、戊二醛交联剂对丝素蛋白/明胶多孔支架的性能影响

为了对比甲醇、戊二醛两种交联剂对丝素蛋白/明胶复合多孔支架的性能影响,采用冷冻干燥法等比例制备该支架,分两组分别用甲醇和戊二醛进行交联。通过观察支架的微观形貌,测量支架的孔隙率、吸水率、溶胀率,测试热稳定性及力学性能,比较经两种交联剂处理后支架结构和性能的变化。结果表明,经戊二醛交联后的支架孔隙分布更加规则、均匀,孔隙率、吸水率、溶胀率更高,力学性能更强。采用戊二醛交联丝素蛋白/明胶复合多孔支架,能够使支架性能更加优良。     

Regulation effect of osteoblasts towards osteocytes by silk fibroin encapsulation

Herein, the rational design micromilieus involved silk fibroin (SF)-based materials have been used to encapsulate the osteoblasts, forming an extracellular coated shell on the cells, which exhibited the high potential to shift the regulation of osteoblasts to osteocytes by encapsulation cues. SF coating treated cells showed a change in cell morphology from osteoblasts-like to osteocytes-like shape compared with untreated ones. Moreover, the expression of alkaline phosphatase (ALP), collagen I (Col I) and osteocalcin (OCN) further indicated a potential approach for inducing osteoblasts regulation, which typically accelerates calcium deposition and cell calcification, presenting a key role for the SF encapsulation in controlling osteoblasts behavior. This discovery showed that SF-based cell encapsulation could be used for osteoblasts behavior regulation, which offers a great potential to modulate mammalian cells’ phenotype involving alternating surrounding cues.     

再生丝素/丝胶蛋白水溶液的同轴干法纺丝

模仿蚕丝的成分、结构和成丝方法,通过同轴干法纺丝初步制备了以添加有金属钙离子（Ca2＋）并调节了pH值的再生丝素蛋白（RSF）为芯层、丝胶蛋白（SS）为皮层的RSF/SS纤维。采用荧光显微镜、扫描电镜、拉曼光谱和材料试验机研究了所得纤维的微观形貌、二级结构和力学性能,并与纯RSF纤维和蚕丝进行了对比。研究结果表明同轴干法纺RSF/SS纤维具有清晰的皮-芯层结构,直径较粗且表面略有皱痕;与纯RSF纤维相比,该初生纤维具有更多的β-折叠构象,力学性能也相对较好,但与天然蚕丝相比尚有较大差距。     

再生丝素/丝胶共混蛋白水溶液的静电纺丝

采用静电纺丝方法制备了再生丝素/丝胶共混纤维,分析了共混配比对再生丝素/丝胶水溶液流变性能和静电纺可纺性的影响,通过扫描电镜、拉曼光谱和DSC等手段研究了所得纤维的形态和微细结构及其力学性能。研究结果表明:随着溶液中丝胶含量的增加,体系的表观粘度增大,静电纺纤维的直径减小且直径分布变窄;并且丝胶的存在有利于丝素蛋白从无规卷曲或α-螺旋结构向β-折叠结构转变,由此可提高静电纺纤维的力学性能。