title: Structural, morphological and optical studies of l-cysteine modified silver nanoparticles and its application as a probe for the selective colorimetric detection of Hg(2+).
abstract: We report an extensive study on the evolution of a highly facile, selective colorimetric probe for Hg(2+) detection using cysteine modified silver nanoparticles. The nanoparticles are stable in a basic medium and the Surface Enhanced Raman Spectrum (SERS) reveal that the cysteine is bound to the Ag surface through the thiolate moiety with the charged carboxylate group pointing outwards in a morphology that lends itself to sensor applications. In the presence of Hg(2+), the absorption peak is quenched resulting in a drastic colour change. The sensor displays high selectivity to Hg(2+) over other metallic ions.
authors.affiliation: P.G. & Research Department of Physics, Lady Doak College, Madurai 625002, Tamil Nadu, India.
authors.forename: M
authors.initials: M
authors.lastname: Nidya
authors.affiliation: Department of Physics, Mother Teresa Women's University, Kodaikanal 624102, Tamil Nadu, India.
authors.forename: M
authors.initials: M
authors.lastname: Umadevi
authors.affiliation: P.G. & Research Department of Physics, Lady Doak College, Madurai 625002, Tamil Nadu, India. Electronic address: beulah_rajkumar@yahoo.co.in.
authors.forename: Beulah J M
authors.initials: BJ
authors.lastname: Rajkumar
mesh_terms: D002413:Cations, Divalent / Q000032:analysis; D003124:Colorimetry / Q000379:methods; D003545:Cysteine / Q000737:chemistry*; D008628:Mercury / Q000032:analysis*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D012834:Silver / Q000737:chemistry*
chemical_list: D002413:Cations, Divalent; D012834:Silver; D008628:Mercury; D003545:Cysteine
keywords: Hg(2+) sensor; SERS; Silver nanoparticles; TEM; l-Cysteine