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991.
基于硫堇衍生化自组装膜的丙肝电化学免疫传感器 总被引:7,自引:0,他引:7
报道了一种制备电流型免疫传感器的新方法。在金电极表面形成巯基自组装单分子层膜,活化后以共价方式竞争键合硫堇分子和丙肝辣根过氧化酶酶标抗体,制得基于硫堇衍生化自组装膜的丙肝电化学免疫传感器。采用循环伏安法和线性扫描伏安法考察了传感器的组装过程,响应电流的性质,以及传感器对丙肝病毒的响应特性,采用线性扫描伏安法对丙肝抗原进行定量分析,线性范围为3.2—16mg/L;检出限为1.2mg/L;线性相关系数r为0.995。取临床血清进行检测,将结果与临床常用的ELISA法比较,探索了该传感器应用于临床检验的可行性。 相似文献
992.
993.
阐述了三螺旋DNA的发展和最新动态,并从3个方面展开评述:(1)三螺旋DNA稳定性的研究。三螺旋DNA的稳定性不仅取决于寡聚核苷酸的内在结构,还受外界环境如溶液的pH值、阳离子的种类和价态、DNA分子嵌入试剂和共聚物等的影响;(2)三螺旋DNA的应用。三螺旋DNA的形成为基因操纵和基因疗法提供了新方法,它在抑制DNA转录、复制、基因定点诱变、定点切割和诱导基因重组等方面有重要的应用前景;(3)三螺旋DNA的检测方法,包括紫外-可见吸收光谱法、荧光分析法、原子力显微术和顺磁共振谱等。 相似文献
994.
995.
A new type of SiO_2-MgO-CaO (SMC) whisker was used to modify high density polyethylene (HDPE).The melting behavior and crystallinity were investigated by differential scanning calorimetry (DSC).The dispersion of whiskers and interfacial adhesion in the prepared HDPE/SMC whisker composites were investigated by scanning electron microscopy (SEM).The mechanical properties were evaluated by mechanical tests and dynamic mechanical analysis (DMA).DSC data indicated that the melting temperature and the crystall... 相似文献
996.
3α-Hydroxyl-7α-(4-pentenoyloxy)-5β-cholanoic acid (5) has been synthesized in four step reactions starting from CDCA. The serendipitous synthesis of methyl 3α-(ethoxycarbonyloxy)-7α-(allyloxycarbonyloxy)-5β-cholanoate (7) has led us to compare the spectroscopic difference of the 7α-(allyloxycarbonyloxy) group versus the 7α-(4-pentenoyloxy) group. The molecular structures of these compounds were confirmed by X-ray crystallography. Methyl 3α-(ethoxycarbonyloxy)-7α-(allyloxycarbonyloxy)-5β-cholanoate was obtained by a method, which may prove useful in the synthesis of 14C-labeled derivatives for metabolic studies. 相似文献
997.
Mingwei Zhao Liqiang Zheng Xiangtao Bai Na Li Li Yu 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,346(1-3):229-236
Silica products with two different morphologies were synthesized using nonaqueous ionic liquid microemulsion droplets as templates. The morphologies of the obtained products were characterized by both transmission electron microscopy (TEM) and scanning electron microscopy (SEM). By adjusting the reaction conditions, ellipsoidal nanoparticles were formed under acidic conditions, while hollow silica spheres were obtained under alkaline conditions. It is demonstrated that the size distribution of hollow silica spheres was narrower than that of the ellipsoidal nanoparticles. The various vibration modes of different functional groups in the silica materials were revealed by Fourier transform infrared (FTIR) spectroscopy. The two samples were both shown to be amorphous, not crystalline by X-ray diffraction (XRD). A simple diagram of the formation process including the hydrolysis and condensation reactions is given. Furthermore, a probable mechanism for the formation of silica materials under acidic or alkaline conditions is presented, which may be helpful for better understanding the different silica materials obtained under different conditions. 相似文献
998.
Hong Chen Wei Song Feng Zhou Zhongkui Wu He Huang Junhu Zhang Quan Lin Bai Yang 《Colloids and surfaces. B, Biointerfaces》2009,71(2):275-281
Chemical homogeneous poly(dimethylsiloxane) (PDMS) surface with dot-like protrusion pattern was used to investigate the individual effect of surface microtopography on protein adsorption and subsequent biological responses. Fibrinogen (Fg) and fibronectin (Fn) were chosen as model proteins due to their effect on platelet and cell adhesion, respectively. Fg labeled with 125I and fluorescein isothiocyanate (FITC) was used to study its adsorption on flat and patterned surfaces. Patterned surface has a 46% increase in the adsorption of Fg when compared with flat surface. However, the surface area of the patterned surface was only 8% larger than that of the flat surface. Therefore, the increase in the surface area was not the only factor responsible for the increase in protein adsorption. Clear fluorescent pattern was visualized on patterned surface, indicating that adsorbed Fg regularly distributed and adsorbed most on the flanks and valleys of the protrusions. Such distribution and local enrichment of Fg presumably caused the specific location of platelets adhered from platelet-rich plasma (PRP) and flowing whole blood (FWB) on patterned surface. Furthermore, the different combination of surface topography and pre-adsorbed Fn could influence the adhesion of L929 cells. The flat surface with pre-adsorbed Fn was the optimum substrate while the virgin patterned surface was the poor substrate in terms of L929 cells spread. 相似文献
999.
Chengbin Jing Haiyang Shan Chuanjian Zhang Xiaodan Zang Wei Bai Junhao Chu 《Journal of Sol-Gel Science and Technology》2009,51(2):139-145
The solids content and gelation time of aqueous germanate solution were examined in this work. Samples of 5, 10 and 20 mol%
Mn doped Ge were prepared by using the aqueous germanate solution as a liquid Ge precursor. No second phase such as Mn5Ge3 was detected in the 5 and 10 mol% Mn doped samples, implying that Mn ions were uniformly diluted into the Ge host matrix.
The 5 and 10 mol% Mn-doped Ge samples exhibit room-temperature ferromagnetic behaviors that are likely originated from the
RKKY (Ruderman–Kittel–Kasuya–Yosida)-like interaction between the localized Mn ions in the Ge matrix. Therefore, the aqueous
germanate solution can be an alternative sol–gel precursor for preparation of the Mn
x
Ge1−x
diluted magnetic semiconductors (DMSs). 相似文献
1000.
Lingyun Chen Hang Xing Junfeng Bai Guoqing Jiang 《Journal of solid state chemistry》2009,182(6):1387-314
Novel MnO nano- and microparticles including spherical nanoparticles and various micropolyhedra of pyramid-like, truncated rectangular pyramid-like, cubic, and rhombic dodecahedral particles, were controllably synthesized via solid-state thermolysis of inorganic core containing molecular clusters [Mn12O12(O2CR)16(H2O)4] (R=C6H5, CH3, and C6H5OCH2) in a conventional horizontal tube furnace. Among them, pyramid-like, truncated rectangular pyramid-like, cubic, and rhombic dodecahedral MnO submicroscale particles were reported for the first time. The products were characterized by XRD, XPS, Raman spectrum, SEM, EDX, TEM and HRTEM. During the reaction process, thermolysis temperature, reaction time, and different molecular clusters {Mn12} precursors with different organic ligands as well play important roles in determining the sizes and shapes of the final products. The formed MnO nanospheres from [Mn12O12(O2CC6H5)16(H2O)4] at 400 °C for 10 h exhibited weak ferromagnetic behavior at low temperature which may be due to the size-effect of nanomaterials. Furthermore, the possible formation mechanism was also discussed. 相似文献