Colorimetric sensing of copper(II) based on catalytic etching of gold nanoparticles

TALANTA

卷:112

Article

Liu, Ruili¹  Chen, Zhaopeng^2,3  Wang, Shasha^2,3,4  Qu, Chengli^2,3  Chen, Lingxin^2,3  Wang, Zhuo¹ 

[1] Yantai Univ, Sch Environm & Mat Engn, Yantai 264003, Peoples R China

[2] Chinese Acad Sci, Yantai Inst Coastal Zone Res YIC, Key Lab Coastal Zone Environm Proc, Yantai 264003, Peoples R China

[3] YICCAS, Shandong Prov Key Lab Coastal Zone Environm Proc, Yantai 264003, Peoples R China

[4] Grad Univ Chinese Acad Sci, Beijing 100049, Peoples R China

关键词: Gold nanoparticle;    Colorimetric;    Copper ion;    Surface plasmon resonance;   

DOI  :  10.1016/j.talanta.2013.01.065

来源: Elsevier

【 摘 要 】

Based on the catalytic etching of gold nanoparticles (AuNPs), a label-free colorimetric probe was developed for the detection of Cu2+ in aqueous solutions. AuNPs were first stabilized by hexadecyltrimethylammonium bromide in NH3-NH4Cl (0.6 M/0.1 M) solutions. Then thiosulfate (S2O32-) ions were introduced and AuNPs were gradually dissolved by dissolved oxygen. With the further addition of Cu2+, Cu(NH3)(4)(2+) oxidized AuNPs to produce Au(S2O3)(2)(3-) and Cu(S2O3)(3)(5-), while the later was oxidized to Cu(NH3)(4)(2+) again by dissolved oxygen. The dissolving rate of AuNPs was thereby remarkably promoted and Cu2+ acted as the catalyst. The process went on due to the sufficient supply of dissolved oxygen and AuNPs were rapidly etched. Meanwhile, a visible color change from red to colorless was observed. Subsequent tests confirmed such a non-aggregation-based method as a sensitive (LOD= 5.0 nM or 032 ppb) and selective (at least 100-fold over other metal ions except for Pb2+ and Mn2+) way for the detection of Cu2+ (linear range, 10-80 nM). Moreover, our results show that the color change induced by 40 nM Cu2+ can be easily observed by naked eyes, which is particularly applicable to fast on-site investigations. (C) 2013 Elsevier B.V. All rights reserved.

【 授权许可】

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