A new rapid colorimetric detection method of Al³⁺ with high sensitivity and excellent selectivity based on a new mechanism of aggregation of smaller etched silver nanoparticles.
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.
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.
Ningning
N
Yang
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.
Yuexia
Y
Gao
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.
Yujie
Y
Zhang
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. Electronic address: shenzheyu@nimte.ac.cn.
Zheyu
Z
Shen
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. Electronic address: aiguo@nimte.ac.cn.
Aiguo
A
Wu
D000535:Aluminum / Q000032:analysis*; D003124:Colorimetry / Q000379:methods; D053768:Metal Nanoparticles / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013997:Time Factors
D012834:Silver; D000535:Aluminum
Aggregation of smaller etched silver nanoparticles; Aluminum ions; Excellent selectivity; High sensitivity; Rapid colorimetric detection