title: Simultaneous electrochemical detection of Cd(II), Pb(II), As(III) and Hg(II) ions using ruthenium(II)-textured graphene oxide nanocomposite.
abstract: Simultaneous determination of Cd(II), Pb(II), As(III) and Hg(II) metal ions was carried out based on the synergistic effect of graphene oxide (GO) textured with redox active ruthenium(II) bipyridine complex ([Ru(bpy)3]2+). [Ru(bpy)3]2+-GO nanocomposite on the modified gold (Au) electrode acts as an electrocatalyst and favours the sensitive and selective detection of metal ions. Also, it exhibited an enhanced electron transfer rate with a low solution resistance examined by cyclic voltammetry and impedance analysis. The inherent electrochemical and electrocatalytic behaviours of [Ru(bpy)3]2+-GO on gold electrode were demonstrated for simultaneous detection of heavy metal ions in water matrix. The proposed sensor exhibited a higher sensitivity towards Cd(II), Pb(II), As(III) and Hg(II) metal ions with a lowest detection limit of 2.8, 1.41, 2.3 and 1.6nM respectively. The observed detection limits were less than the World Health Organization standards and hence the developed sensor can be deployed for detecting heavy metal ions in water bodies. Simultaneous electrochemical detection of heavy metal ions in river and tap water was carried out using the developed sensor and the observed results were validated with atomic absorption spectroscopy.
authors.affiliation: Nano Sensors Lab @ Centre for Nanotechnology & Advanced Biomaterials (CeNTAB), SASTRA University, Thanjavur 613401, Tamil Nadu, India; School of Electrical & Electronics Engineering, SASTRA University, Thanjavur 613401, Tamil Nadu, India.
authors.forename: Manju Bhargavi
authors.initials: MB
authors.lastname: Gumpu
authors.affiliation: National Institute of Pharmaceutical Education and Research, Kolkata 700032, West Bengal, India.
authors.forename: Murugan
authors.initials: M
authors.lastname: Veerapandian
authors.affiliation: School of Chemical and Biotechnology, SASTRA University, Thanjavur 613401, Tamil Nadu, India.
authors.forename: Uma Maheswari
authors.initials: UM
authors.lastname: Krishnan
authors.affiliation: Nano Sensors Lab @ Centre for Nanotechnology & Advanced Biomaterials (CeNTAB), SASTRA University, Thanjavur 613401, Tamil Nadu, India; School of Electrical & Electronics Engineering, SASTRA University, Thanjavur 613401, Tamil Nadu, India. Electronic address: rjbosco@ece.sastra.edu.
authors.forename: John Bosco Balaguru
authors.initials: JB
authors.lastname: Rayappan
keywords: Graphene oxide; Heavy metal ions; Redox-active nanocomposite; Ruthenium(II) bipyridine; Simultaneous detection