Yang Ningning, Gao Yuexia, Zhang Yujie, Shen Zheyu, Wu Aiguo
Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China; Division of Functional Materials and Nano Devices, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China.
Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China; Division of Functional Materials and Nano Devices, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China; The School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, China.
Talanta. 2014 May;122:272-7. doi: 10.1016/j.talanta.2014.01.035. Epub 2014 Jan 31.
As a pathogenic factor of the Alzheimer׳s disease, aluminum has been associated with the damage of the central nervous system in humans. In this study, we propose a new facile and rapid colorimetric detection method of Al(3+) with excellent selectivity and high sensitivity based on silver nanoparticles (AgNPs) stabilized by reduced glutathione (GSH) in the presence of l-cysteine (Cys). The new mechanism of our Al(3+) detection system based on GSH-AgNPs, i.e., aggregation of smaller etched GSH-AgNPs, are confirmed by TEM, EDS and DLS. The aggregation of smaller etched GSH-AgNPs results in obvious color change of the nanoparticle dispersion from yellow to reddish brown, and red shift and intensity decrease of the surface plasmon resonance (SPR) absorption. The GSH concentration, Cys concentration and pH value of the GSH-AgNPRs-based detection system are respectively optimized to be 10.0 mM, 50.0 mM and 6.0 according to the sensing effect of Al(3+). At the optimized conditions, the selectivity of the GSH-AgNPs detection system for Al(3+) is excellent compared with other ions including K(+), Mg(2+), Fe(3+), Co(2+), Mn(2+), Zn(2+), Cd(2+), Pb(2+), Ca(2+), Ba(2+), Cu(2+), Cr(3+), Hg(2+), Ni(2+), [Formula: see text] , [Formula: see text] , [Formula: see text] , [Formula: see text] and [Formula: see text] . Furthermore, this detection system is very sensitive for Al(3+). The limit of detection (LOD) is 1.2 µM by the naked eyes and 0.16 µM by UV-vis spectra, which are both much lower than the national drinking water standards (7.4 µM). Furthermore, the UV-vis detection offers a good linear detection range from 0.4 to 4.0 µM (R(2)=0.9924), which indicates that our developed detection system can also be used for the quantitative analysis of Al(3+). The detection results of real water samples indicate that this method can be used for real water detection.
作为阿尔茨海默病的致病因素，铝已被证实与人类中枢神经系统损伤有关。在本研究中，我们提出了一种基于谷胱甘肽（GSH）稳定的银纳米颗粒（AgNPs），在L-半胱氨酸（Cys）存在下，对Al(3+)进行简便快速比色检测的新方法，该方法具有优异的选择性和高灵敏度。基于GSH-AgNPs的Al(3+)检测系统的新机制，即较小蚀刻GSH-AgNPs的聚集，通过透射电子显微镜（TEM）、能谱仪（EDS）和动态光散射（DLS）得到证实。较小蚀刻GSH-AgNPs的聚集导致纳米颗粒分散液颜色从黄色明显变为红棕色，表面等离子体共振（SPR）吸收发生红移且强度降低。根据Al(3+)的传感效果，将基于GSH-AgNPRs的检测系统中的GSH浓度、Cys浓度和pH值分别优化为10.0 mM、50.0 mM和6.0。在优化条件下，与包括K(+)、Mg(2+)、Fe(3+)、Co(2+)、Mn(2+)、Zn(2+)、Cd(2+)、Pb(2+)、Ca(2+)、Ba(2+)、Cu(2+)、Cr(3+)、Hg(2+)、Ni(2+)、[化学式：见原文]、[化学式：见原文]、[化学式：见原文]、[化学式：见原文]和[化学式：见原文]在内的其他离子相比，GSH-AgNPs检测系统对Al(3+)具有优异的选择性。此外，该检测系统对Al(3+)非常敏感。肉眼检测限（LOD）为1.2 μM，紫外可见光谱检测限为0.16 μM，均远低于国家饮用水标准（7.4 μM）。此外，紫外可见检测提供了0.4至4.0 μM的良好线性检测范围（R(2)=0.9924），这表明我们开发的检测系统也可用于Al(3+)的定量分析。实际水样的检测结果表明该方法可用于实际水样检测。
