基于超支化聚合物稳定的金纳米粒子比色传感器的制备、表征及应用

发布时间：2018-03-04 00:26

  本文选题：温敏聚合物　切入点：金纳米粒子　出处：《鲁东大学》2017年硕士论文　论文类型：学位论文

【摘要】：本论文通过异丁酸酐与超支化聚乙烯亚胺的胺基反应制备了具有温敏特性的异丁酰化超支化聚乙烯亚胺(HPEI-IBAm)。以具有大量胺基的HPEI-IBAm为还原剂,可将氯金酸还原制备出稳定的金纳米粒子。这种通过HPEI-IBAm与氯金酸原位还原反应制备AuNPs的方法不需要另外加入小分子毒性还原剂,绿色环保,具有重要意义。基于HPEI-IBAm稳定的金纳米粒子(AuNPs)不仅可实现对银离子的比色传感检测,还能实现对检测后的AuNPs/银复合物的分离。其比色检测的机理为HPEI-IBAm可将银离子还原成单质银,单质银吸附在AuNPs(红色)表面,形成核壳金-银纳米粒子(棕色)。HPEI-IBAm具有很高的空间位阻效应,不仅可以稳定金纳米粒子,而且还可以为金-银核壳纳米粒子提供很好的稳定作用,能够使其长时间稳定存在而不聚集,便于在颜色变化后对其进行观察和记录。这种基于形成稳定金-银核壳纳米粒子伴随出现红色到棕色独特变化的比色传感相比传统的因AuNPs聚集引起红到紫色(或蓝色)变化的传感器具有更高的选择性。因为诸如在酸度、温度过高或固体状态存在时都会引起传统AuNPs聚集伴随红到紫色的颜色变化,干扰检测结果的准确性。并且聚集态的金纳米粒子是不稳定的,因此变化后的颜色不能长时间保持,不利于观察记录。整个检测反应过程迅速,大约在0.5-1分钟左右就可以达到稳定的颜色变化状态。同时,该比色传感器对银离子的比色检测具有高的灵敏度,其肉眼可分辨的检测限为5.73?(44),紫外可见光谱检测限为5.73 nM(远低于美国环境保护署制定的饮用水中银离子的最高含量标准0.1 mg/L≈920 nM)。这种基于聚合物稳定的金纳米粒子对银离子的检测,相比小分子还原法制备金纳米粒子的传统比色传感检测具有更多的优势:(1)温敏聚合物不仅可以作为绿色的还原剂和稳定剂,把银离子还原为零价的银纳米粒子,然后沉积在金纳米粒子的表面,使得体系有很明显的颜色变化,而且也是很好的分离剂,在检测后可以利用其温敏特性,把传感器和银的混合物分离出来。(2)聚合物稳定的金纳米粒子可以实现制备、检测和分离的一体化,有利于节约能源、保护环境和实现可持续发展,并且为以后开发多功能纳米复合材料提供了很好的思路。(3)这种聚合物制备的金纳米粒子的稳定性(即使在高温、酸性介质、固体粉末和高离子强度下)高,主要得益于聚合物末端有大量的胺基基团和高的空间位阻效应,可以有效的避免酸性介质和高离子强度的干扰以提高检测银离子的选择性和唯一性。(4)这种金纳米粒子比色检测的颜色变化是由红色到棕色的颜色变化,而且这种红色到棕色的颜色变化是唯一的,可以通过眼睛观察,展示了检测体系的高灵敏度和对银离子的高选择性,(5)检测后基于聚合物的温敏特性,通过简单的加热沉淀或离心可实现AuNPs/Ag复合物的分离,可避免二次污染。
[Abstract]:In this paper, the iso-butyloyl hyperbranched polyimide (HPEI-IBAmN) was prepared by the reaction of isobutyric anhydride with the amine group of hyperbranched polyimine. HPEI-IBAm with a large number of amino groups was used as reducing agent. Stable gold nanoparticles can be prepared by reduction of chlorauric acid to prepare AuNPs by in-situ reduction reaction of HPEI-IBAm with chlorauric acid, which does not require the addition of small molecular toxic reductants, which is green and environmentally friendly. The au nanoparticles based on HPEI-IBAm can not only detect the silver ions, but also separate the silver complexes of AuNPs/. The mechanism of the colorimetric detection is that the silver ions can be reduced to silver by HPEI-IBAm. The adsorbed silver on the surface of AuNPs (red) forms a core-shell gold-silver nanoparticles (brown. HPEI-IBAm) with a high steric resistance effect, which can not only stabilize the gold nanoparticles, but also provide a good stability for the gold-silver core-shell nanoparticles. Can keep it stable for a long time without gathering, This colorimetric sensor based on the formation of stable gold-silver core-shell nanoparticles with unique red to brown variations is easier to observe and record when the color changes occur compared to the traditional red-purple resulting from AuNPs aggregation (or. Blue) changes in the sensor have higher selectivity because, for example, in acidity, When the temperature is too high or the solid state exists, the traditional AuNPs aggregation will be accompanied by the color change from red to purple, which will interfere with the accuracy of the detection results. Moreover, the gold nanoparticles in the aggregated state are unstable, so the color after the change cannot be maintained for a long time. It is not good for observation record. The whole process of detection reaction is rapid, and can reach a stable color change state in about 0.5-1 minute. At the same time, the colorimetric sensor has high sensitivity to the colorimetric detection of silver ions. The detectable limit of its naked eye is 5.73? The UV / Vis detection limit is 5.73 nm (which is far below the US Environmental Protection Agency's highest standard for silver ions in drinking water: 0.1 mg/L 鈮，

本文编号：1563368