氧化石墨烯/磷酸钙生物水泥体外生物相容性研究

等摩尔的Ca_3(PO_4)2-CaHPO_4-CaCO_4(CPCs)水泥系为固相,不同质量浓度的氧化石墨烯(GO)水分散液(0~24mg/mL)为液相,按一定的固液比固化,得到复合材料GO/CPCs.以成骨细胞MC3T3-E1为对象,初步探究该复合材料试样的体外生物相容性.扫描电镜观察细胞贴壁形态,MTT法评价细胞活力,碱性磷酸酶(ALP)活性检测探讨材料的骨诱导性.结果显示:MC_3T3-E1细胞在材料表面状态良好,产生胞质突;GO的添加能够增强MC3T3-E1细胞活力;GO/CPCs在短期内(1d)促进MC3T3-E1细胞早期分化.GO/CPCs有望成为一种新型骨组织替代材料.     

Cellular response to titanium discs coated with polyelectrolyte multilayer films

The purpose of this study was to investigate the effects of polyelectrolyte multilayer (PEM) coatings on the biological behavior of titanium (Ti) substrates. Collagen type Ι/hyaluronic acid (Col/HA) and chitosan/hyaluronic acid (Chi/HA) multilayer PEM coatings were introduced onto Ti substrates using layer-by-layer assembly. Contact angle instruments and quartz crystal microbalance were used for film characterization. The results obtained showed that both Col/HA and Chi/HA surfaces had high hydrophilicity and promoted cell adhesion in MC3T3-E1 pre-osteoblast and human gingival fibroblast cells. In addition, the synthesis of function-related proteins and gene expression levels in both MC3T3-E1 and fibroblast cells was higher for the Col/HA coating compared with the Chi/HA coating, indicating better cellular response to the Col/HA coating.     

低强度脉冲超声对MC3T3-E1细胞增殖、分化和矿化的影响

 为了研究低强度脉冲超声促进MC3T3-E1细胞增殖、分化和矿化的有效性,初步筛选频率和强度参数,分别对细胞施加不同参数(频率、强度)的超声,采取CCK-8法检测细胞的增殖情况,碱性磷酸酶检测试剂盒检测分化效果,茜素红染色观察矿化效果。发现30mW/cm²和40mW/cm²的超声对细胞产生促增殖作用,50mW/cm²抑制增殖;1.5MHz和1.7MHz的较低强度组均较对照组的ALP活性有增加;1.5MHz,40mW/cm²的超声组矿化效果较其他组好。研究结果表明,低强度的脉冲超声可以提高成骨细胞株MC3T3-E1增殖、分化和矿化能力,可能是防治骨质疏松的可行手段之一。     

Effects of Quenching Temperature and Time on Pore Diameter of Poly（3-hydroxybutyrate-co-3-hydroxyhexanoate） Porous Scaffolds and MC3T3-E1 Osteoblast Response to the Scaffolds

Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) scaffolds were prepared by thermally inducing phase separation (TIPS) for bone reconstruction. Scanning electron microscopy and porosity measurements were used to analyze the structure and properties of the scaffolds. The pore diameter of the scaffolds could be easily controlled by changing the quenching temperature and time. The biocompatibility was assessed by examining the proliferation and morphology of MC 3T3-E1 osteoprogenitor cells seeded on the scaffolds. Cultures grown in the presence of a source of phosphate ions showed the formation of a mineralized extracellular matrix. The results indicate that PHBHHx scaffolds prepared using TIPS are a promising candidate for bone reconstruction.     

HPEI接枝改性PAN/GO-PAA静电纺纳米复合纤维膜对Au(Ⅲ)的吸附

以丙烯酸(AA)为单体,过氧化苯甲酰(BPO)为引发剂,通过原位聚合法,在氧化石墨烯(GO)表面包覆聚丙烯酸(PAA),得到GO-PAA纳米复合物.将GO-PAA纳米复合物分散在聚丙烯腈(PAN)基体中,利用静电纺丝技术得到PAN/GO-PAA静电纺纳米复合纤维膜.利用化学接枝反应在PAN/GO-PAA静电纺纳米复合纤维膜表面接枝超支化聚乙烯亚胺(HPEI),构筑HPEI-g-PAN/GO-PAA静电纺纳米复合纤维膜.研究了HPEI-g-PAN/GO-PAA静电纺纳米复合纤维膜对Au(Ⅲ)的吸附性能.结果表明:HPEI-g-PAN/GO-PAA静电纺纳米复合纤维膜对Au(Ⅲ)的最大吸附量为1 808.60 mg·g^－1,在吸附过程中,部分Au(Ⅲ)被还原为片状和不规则颗粒状的Au单质.在共存离子体系中,HPEI-g-PAN/GO-PAA对Au(Ⅲ)具有较好的吸附选择性.     

新型AgBr/GO复合催化剂的制备及其可见光催化还原CO2性能的初步研究

 采用液相合成法,在十三烷基三甲基溴化铵（CTAB）辅助下制备具有可见光效应的AgBr/GO复合材料,并考察其在可见光下催化还原CO₂制备碳氢化合物的可行性及催化性能。XRD和TEM结果表明：AgBr纳米颗粒均匀地分散在GO载体表面,有利于光诱导下产生的电荷在AgBr与GO界面间的有效传递。可见光照射下,AgBr/GO复合催化剂还原CO₂生成的甲烷、甲醇、CO和乙醇的产量分别是106.11、64.20、26.53和10.96 μmol·g^-1,明显高于AgBr的催化活性。AgBr/GO在重复使用5次后其光催化还原CO₂的活性基本保持不变,因此AgBr/GO是一种高效的、光化学性质稳定的催化剂。     

负载丝裂霉素C的聚乳酸微球制备及细胞生长抑制作用研究

利用单乳化溶剂挥发法制备负载丝裂霉素C（MMC）的聚乳酸（PLA）载药微球. 优化载药微球的制备条件,当药物与载体聚合物比例为10:90时,微球的实际载药量与包封率分别达到最高值5.62%与49.1%;采用SEM对微球形貌进行表征;对载药微球的体外释药进行研究,结果表明载药微球无明显暴释现象,可有效缓释MMC达30天以上,累计释放量为84.8%;细胞实验结果表明,载药微球可以有效抑制小鼠NIH-3T3成纤维细胞的增殖.     

Fe3O4/SiO2/石墨烯-CdTe量子点/CS纳米复合材料对smcc-7 721细胞的毒性研究

研究磁性Fe₃O₄/SiO₂/石墨烯-CdTe量子点/脱乙酰壳多糖纳米复合材料(FGQCs)提高药物传输效率的潜力。通过MTT法检测细胞活力,相差倒置显微镜观察给药后的细胞生长形态,流式细胞仪检测药物载体混悬液(5-FU-FGQCs)对smmc-7 721细胞增殖的影响。实验结果表明,FGQCs具有良好的生物相容性,5-FU-FGQCs具有更高的药物输送效率证明FGQCs增强了5-FU药物的细胞毒性。     

A Biodegradable Knitted Cardiac Patch for Myocardium Regeneration Using Cardiosphere-Derived Cells(CDCs)

In order to regenerate myocardium and provide appropriate mechanical support after a heart attack,jersey,tuck and rib stitch structures were knitted from polylactic acid(PLA)yarns to fabricate a cardiac patch,which mimicked the mechanical properties of myocardium in both directions.Cardiosphere-derived cells(CDCs) were seeded on these PLA patch fabrics,and using scanning electron microscopy(SEM) characterization and an MTT assay the cells proliferated and attached successfully to the PLA fabrics.Based on the results,the rib stitch structure is the most promising candidate for fabricating cardiac patches due to its high elasticity and its ability to promote cell proliferation.     

石见穿萃取物对体外培养成骨细胞活性的影响

石见穿以95%乙醇抽提得总提物.分别用不同试剂萃取总提物,获得其石油醚萃取物、乙酸乙酯萃取物、正丁醇萃取物以及其水溶性成分.以体外培养成骨细胞MC3T3-E1为模型,用cck-8法测定细胞增殖,碱性磷酸酶(ALP)试剂盒法测定了上述不同萃取物对成骨细胞增殖和分化的影响.结果表明:总提物在浓度10～-3、10-4、10-...     

聚苯胺/SnO_2/氧化石墨烯复合物的制备及电容性质

采用简单的方法制备PANI/SnO2/GO复合物,利用X射线衍射仪、透射电子显微镜、红外光谱仪和热重分析仪对所得产物的结构和形貌进行表征,并利用循环伏安法、交流阻抗谱和恒电流充放电实验研究所得产物的电化学性质和电容特性.结果表明:所制备的PANI/SnO2/GO复合物具有较高的比电容,经过1 000次循环后表现出良好的稳定性.     

Behavior of MC3T3-E1 Osteoblast Cultured on Chitosan Modified with Polyvinylpyrrolidone

The physical and chemical properties of four kinds of modified chitosan materials made by blending chitosan with polyvinylpyrrolidone （PVP） were investigated. All four of these modified chitosan materials were hydrophilic with water contact angles ranging from 59°to 69°. Fourier transform-infrared spectra of the modified materials showed a new band at 1288 cm^-1, implying formation of a surface physical interpenetrating network structure. Enzyme linked immunosorbent assay results indicated that much less fibronectin was adsorbed on the modified materials than on only chitosan. The viability of MC3T3-E1 osteoblasts cultured on the materials was assessed by 3-（4,5-dimethyl-2-thiazolyl）-2,5-diphenyl- 2H-tetrazolium bromide assay. The results show that adding PVP10000 into the chitosan promotes adhesion of MC3T3-E1 osteoblasts on the modified materials, but has no effect on cell growth and proliferation; while adding PVP40000 reduces cell adhesion, growth, and proliferation. The results suggest that the increased hydrophilicity of the material surface does not always improve its biocompatibility, which will influence the selection and design of biomaterials.     

银/聚吡咯/二氧化钛复合纳米粒的制备与结构表征

以钛酸四丁酯、硝酸银和吡咯为原料采用溶胶-凝胶法制备了银/聚吡咯/二氧化钛(Ag/PPy/TiO2)复合纳米粒,考察了PPy单体用量、原料配比等因素对制备复合纳米粒的影响。运用扫描电镜(SEM)、透射电镜(TEM)、红外光谱仪(FTIR)等测试方法对复合纳米粒进行了表征。结果表明,Ag/PPy/TiO2复合纳米粒具有棒状的核壳结构,聚吡咯包覆在Ag和TiO2纳米粒子的表面。     

sPS/PA66/g-sPS/纳米A12O3粒子复合材料性能

以间规聚苯乙烯sPS-sPS/Al2O3纳米粒子复合材料;测量了纳米复合材料的力学性能和热性能,并用扫描电[英文作者]PA66/g复合,制备出sPS-sPS合金具有明显的增韧增强[英文作者]PA66/g镜观察了材料的显微组织结构.研究结果表明:纳米Al2O3粒子对于sPS/PA99/g-sPS合金具有明显的增韧增强作用;随着纳米A12O3粒子质量为6g时,复合材料的拉伸强度最大,纳米复合材料的冲击强度和拉伸强度均出现先升高后下降的变化趋势.     

Functionalization of PCL fibrous membrane with RGD peptide by a naturally occurring condensation reaction

Poly(e-caprolactone)(PCL)is widely adopted as an ingredient for tissue engineering scaffolds.To improve its cell affinity,in this study,we developed a new method to introduce bioactive RGD peptides onto the surface of PCL via condensation reaction between 2-cyanobenzothiazole(CBT)and D-cysteine.The PCL fibrous membranes were prepared by electrospinning,and RGD functionalization was characterized by fluorescence microscopy,scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS)and water contact angle(WCA).As expected,our results demonstrated the successful RGD immobilization on the surface of PCL.RGD modification improved the hydrophilicity of PCL,changing their WCA from 112.20°to38.35°.Cell adhesion,spreading and proliferation of 3T3fibroblasts were also enhanced.We therefore believe that the methods reported in this study was facile and effective for functional modification of the hydrophobic PCL scaffolds.The moderate reaction conditions are also suitable for covalent immobilization of bioactive molecules onto PCL.     

Lyocell纤丝及其可生物分解的纳米复合材料研究

可生物分解的纳米复合材料是新一代材料,微米和纳米级纤维素纤丝具有环保性和潜在的低密度及高强度,可用来制造能生物分解的纳米复合材料.为了描述用一种新的机械方法从Lyocell纤维中分离出的纤丝的特性,以及探索这种纤丝能否增强生物分解的聚合物,笔者用偏振光显微镜(PLM)和扫描电子显微镜(SEM)研究了纤丝的几何特性,用宽角X光衍射法(WAXD)分析了其结晶度,纤维的纤丝化程度用水分保持值(WRV)进行了评价;纤丝增强的聚乳酸(PLA)纳米生物复合材料由模压法制备,用拉伸试验来检测其力学强度,采用SEM来观察其断面特性.结果表明:纤丝提高了PLA的弹性模量和拉伸强度,但纤丝和聚合物基质之间的结合强度很弱.     

In vitro study of human endothelial progenitor cells behaviour on nitrided Ni-free Ti–27Nb alloy

A superelastic Ni-free Ti–27Nb alloy has been synthesized and gas nitrided at high temperature to investigate its suitability for vascular implant applications. The cellular responses of human endothelial progenitor cells (EPCs) to both bare and nitrided Ti–27Nb alloy have been analyzed using Live/Dead staining, MTT assay, fluorescence microscopy and ELISA technique, as well as NiTi alloy for comparison. Live/Dead staining and MTT assay were performed to assess the cellular viability and proliferation, while fluorescence microscopy was used to analyze cell adhesion, cell morphology, and the expression of endothelial cell markers (VE-cadherin and von Willebrand factor). Secretion of the pro-inflammatory chemokine MCP (monocyte chemoattractant protein)-1 by the cells grown in contact with the analyzed materials was further verified using the enzyme-linked immunosorbent assay. The results obtained revealed that adhesion, spreading, viability, proliferation rate and phenotypic markers expression of EPCs were similar on the surfaces of Ti–27Nb and NiTi alloys. Cells exposed to nitrided Ti–27Nb surface exhibited significantly decreased inflammatory response, which may be beneficial for reducing in-stent restenosis incidence.     

细胞周期检测作为生物相容性评价指标的研究

应用体外细胞培养法,观察不同质量分数羟基磷灰石浸提液对L-929细胞的细胞学形态的影响,同时采用MTT比色法评价羟基磷灰石对L-929生长和增殖的影响,流式细胞仪检测羟基磷灰石浸提液对L-929 细胞生长周期及凋亡的影响.结果表明,羟基磷灰石浸提液对体外培养的细胞形态无明显影响,对细胞生长和增殖无明显抑制作用;不同质量分数材料浸提液的细胞毒性为0～1级;随羟基磷灰石浸提液质量分数的升高,细胞凋亡率逐渐上升;50%、75%、100%羟基磷灰石浸提液组能明显降低G0/G1期细胞比例,增加S,G2/M期细胞比例,能增加L-929细胞DNA的合成,促进细胞生长和组织修复.细胞周期检测是生物材料生物相容性评价的一种可靠方法和指标.     

玻片表面硅烷/氧化石墨烯复合涂层的制备及其摩擦性能

使用硅烷偶联剂 3-氨丙基甲基二甲氧基硅烷(3-(dimethoxymethylsilyl)propylamine) 和不同氧化程度的氧化石墨烯(graphene oxide, GO)在玻片表面采用浸渍法制备了一种在水环境下具有较好润滑性能的氧化石墨烯涂层. 通过傅里叶变换红外光谱 (Fourier transform infrared spectrometer, FTIR)仪、拉曼光谱(Raman spectra)分析法、水接触角(water contact angle, WCA)测试等方法研究了涂层的表面形貌及其特征. 研究结果表明, 所制备的硅烷/氧化石墨烯涂层表面均一, 没有明显的缺陷. 摩擦测试结果显示, 涂层能够有效提高耐磨性能, 不同氧化程度的氧化石墨烯对抗磨性能有着不同的影响, 氧化程度越高, 抗磨性能越好.