title: Fast colorimetric detection of copper ions using L-cysteine functionalized gold nanoparticles.
abstract: This communication reports an efficient visual detection method of Cu2+ by L-cysteine functionalized gold nanoparticles in aqueous solution. Upon exposure to Cu2+, the gold nanoparticle solution changed from red to blue, in response to surface plasmon absorption of dispersed and aggregated nanoparticles. This colorimetric sensor allows a rapid quantitative assay of Cu2+ down to the concentration range of 10(-5) M. Recognition of Cu2+ and formation of the aggregates are proposed to occur via a 2 : 1 sandwich complex between L-cysteine and Cu2+.
authors: School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia.
authors: Wenrong
authors: W
authors: Yang
authors: J Justin
authors: JJ
authors: Gooding
authors: Zhicong
authors: Z
authors: He
authors: Qiong
authors: Q
authors: Li
authors: Guonan
authors: G
authors: Chen
mesh_terms: D003124:Colorimetry; D003300:Copper / Q000032:analysis / Q000737:chemistry*; D003545:Cysteine / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D007477:Ions / Q000032:analysis / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D008956:Models, Chemical; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods; D010316:Particle Size; D020349:Surface Plasmon Resonance; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D007477:Ions; D014867:Water; D006046:Gold; D003300:Copper; D003545:Cysteine