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基于硫化镉纳米团簇标记DNA电化学传感的研究 总被引:3,自引:2,他引:3
合成了表面具有自由羧基的硫化镉纳米团簇,以乙基-(3-二甲基丙基)碳二 亚胺盐酸盐为偶联活化剂,将其标记于人工合成的5'端氨基修饰的寡聚核苷酸片段 上,制备成CdS纳米团簇标记DNA探针,该寡聚核苷酸片段与大肠杆菌肠毒素基因相 关。在一定的条件下,使基与固定晨玻碳电极表面的待测DNA序列进行杂交反应, 利用阳极溶出示差脉冲伏安法(ASDPV)间接测定Cd的量,实现对互补、非互补 DNA片段的识别和电化学检测,从而对大肠杆菌肠毒素基因片段识别和检测。 相似文献
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在模拟人体生理条件下,采用紫外光谱法、荧光光谱法和同步荧光光谱法研究查尔酮、4′-甲氧基查尔酮和4′-氯查尔酮与人血清白蛋白(HSA)的相互作用及其构效关系。实验表明:三种查尔酮类化合物对HSA的荧光猝灭机制主要为静态猝灭,与HSA均形成1∶1复合物,结合常数K分别为2.50×104、0.697×104和0.277×104 L.moL-1,结合距离r分别为3.78、3.93和4.25nm,其作用力均以氢键和范德华力为主。查尔酮类化合物中取代基的不同对其与HSA的结合产生影响,其作用力大小依次为查尔酮>4′-甲氧基查尔酮>4′-氯查尔酮。 相似文献
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冰醋酸是最重要的有机酸之一,甲酸是冰醋酸中的主要杂质,其含量的多少直接影响冰醋酸的质量。现行国内外标准方法是利用化学方法对冰醋酸中微量的甲酸进行测定,其操作步骤繁琐,费时费力,完成测定工作约需要几个工作日,无法满足贸易结算的快速测定的需要。目前微量甲酸一般采用衍生气相色谱法测定。对甲酸直接定量测定的方法有离子色谱法、气相色谱/质谱法(GC/MS)以及气相色谱/热导检测法(TCD)。本文利用电子捕获检测器(ECD)检测甲酸,避免了衍生化或者标记方法的繁琐及化学法费时费力的缺点,而且其灵敏度远远优于TCD和氢火焰离子化检测器(FID),同时又克服了MS检测器不易定量的缺点,为进口冰醋酸的准确快速测定提供了技术保证。 相似文献
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Cu、Ag、Au掺杂BiVO_4可见光催化剂的制备及性能研究 总被引:1,自引:0,他引:1
水热法制备了币族金属(Cu、Ag和Au)掺杂的BiVO4可见光催化剂,借助X-射线衍射(XRD)、X-射线光电子能谱(XPS)、紫外-可见漫反射光谱(DRS)和扫描电子显微镜(SEM)对其进行表征.XRD分析显示所有催化剂都呈现单斜结构.XPS结果显示掺杂元素均以其稳定氧化态形式存在与催化剂表面.DRS谱中掺杂样品的吸收边界比纯BiVO4都有不同程度的红移.以甲基橙的可见光催化降解反应为探针,研究了催化剂的可见光催化性能.结果表明,经币族金属掺杂改性的催化剂催化能力比纯BiVO4有所提高.对其掺杂增强催化能力的可能原因进行了分析讨论. 相似文献
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The biosorbent has been prepared with the sophora japonica leaves from the agricultural residue as the raw material by the alkaline blanching method, and characterized by BET, SEM, EDS and FTIR analysis methods. The modified sophora japonica leaves possessed more adsorption sites and had more strongly adsorbed chemical groups, which were beneficial to the adsorption. We have further investigated the adsorption performance of the indoor benzene. The secondary regression orthogonal rotation was employed to optimize the preparation process for the optimal processing conditions and regression model. The effects of single factors such as particle size, temperature, and adsorbent dosage of the sophora japonica leaves were analyzed, and adsorption isotherms and adsorption kinetics were studied. The results show that the optimal adsorption conditions were as follows: sodium hydroxide concentration with 0.1 mol/L, water bath time for 70 min, water bath temperature at 60 ℃ and Ymax = 21.38%. The best single factors included particle size with 30 mesh, temperature at 25 oC, 3 g dosage, which are consistent with the Freundlich model, and the adsorption state was more inclined to multilayer active site adsorption with 25 mg/g of saturated adsorption amount; furthermore, the adsorption kinetics followed the quasi-secondary kinetic model(R2 = 0.9731) and the adsorption process was a physicochemical mixed adsorption process controlled by chemisorption; Compared with the adsorption effect, the removal rate to the benzene of modified sophora japonica leaves was significantly superior to other materials at the level 1%, namely, modified sophora japonica leaves diatomite bamboo charcoal activated carbon macroporous resin, and the modified biosorbent had a good cycle regeneration ability. 相似文献
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