title: Selective colorimetric sensing of cysteine in aqueous solutions using silver nanoparticles in the presence of Cr³+.
abstract: We here in report an extensive study on the development of a highly facile, selective and sensitive colorimetric probe for cysteine detection using silver nanoparticles (Ag NPs). The efficacy of the process relies upon the surface plasmon resonance properties of Ag NPs and the interaction of Ag-cysteine complex with chromium ions (Cr(3+)) in a ratio of 2:1. In the presence of Cr(3+), cysteine was able to induce the aggregation of Ag NPs thereby resulting in a change in yellow colour of the Ag colloid to purple. The reported probe has a limit of detection down to 1 nM which is to the best of our knowledge the lowest ever reported for the colorimetric detection of cysteine. Furthermore, a remarkable feature of this method is that it involves a simple technique exhibiting high selectivity to cysteine over other tested amino acids.
authors.affiliation: Nano-biomedicine Research Group, School of Bio Sciences & Technology, VIT University, Vellore 632014, India.
authors.forename: Aswathy
authors.initials: A
authors.lastname: Ravindran
authors.forename: Vinayak
authors.initials: V
authors.lastname: Mani
authors.forename: N
authors.initials: N
authors.lastname: Chandrasekaran
authors.forename: Amitava
authors.initials: A
authors.lastname: Mukherjee
mesh_terms: D002857:Chromium; D003124:Colorimetry / Q000379:methods* / Q000592:standards; D003545:Cysteine / Q000032:analysis*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry*; D015336:Molecular Probe Techniques / Q000592:standards; D012834:Silver; D012996:Solutions; D014867:Water
chemical_list: D012996:Solutions; D014867:Water; D002857:Chromium; D012834:Silver; D003545:Cysteine