A coordination and ligand replacement based three-input colorimetric logic gate sensing platform for melamine, mercury ions, and cysteine

• Published in: RSC advances 2015-01, Vol.5 (73), p.5916-59113
• Main Authors: Zhang, Lulu, Yuan, Yanwen, Wen, Xinglin, Li, Yue, Cao, Cuong, Xiong, Qihua
• Format: Article
• Language: English
• Subjects: Cysteine; Detection; Gates; Gold; Ligands; Logic; Melamine; Platforms
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/c5ra09570k

Discrimination of different species in various target scopes within a single sensing platform can provide many advantages such as simplicity, rapidness, and cost effectiveness. Here we design a three-input colorimetric logic gate, based on the aggregation and anti-aggregation of gold nanoparticles (Au NPs), for the sensing of melamine, cysteine, and Hg 2+ . The concept makes use of the advantages of the highly specific coordination and ligand replacement reactions between melamine, cysteine, Hg 2+ , and Au NPs. Different outputs are obtained with the combinational inputs in the logic gates, which can serve as a reference to discriminate different analytes within a single sensing platform. Furthermore, besides the intrinsic sensitivity and selectivity of Au NPs to melamine-like compounds, the "INH" gates of melamine/cysteine and melamine/Hg 2+ in this logic system can be employed for sensitive and selective detections of cysteine and Hg 2+ , respectively. A three-input colorimetric logic gate of melamine, cysteine, and Hg 2+ using Au NP has been reported, in which the colour changes of the Au NPs solution provide sensitive and selective detections of melamine, cysteine, and Hg 2+ .