title: Selective detection of Cu2+and Co2+in aqueous media: Asymmetric chemosensors, crystal structure and spectroscopic studies.
abstract: Two new azo-azomethine receptors, H2L1and H2L2, containing hydrazine, naphthalene and different electron withdrawing groups, Cl and NO2, have been designed and synthesized for qualitative and quantitative detection of Cu2+and Co2+in aqueous media. The crystal structure of H2L1is reported. The H2L1was used as a chemosensor for selective detection of trace amount of Cu2+in aqueous media. H2L2was also applied to naked-eye distinction of Cu2+and Co2+from other transition metal ions in aqueous media. Detection limit of Cu2+is 1.13μM and 1.26μM, in water, for H2L1and H2L2, respectively, which are lower than the World Health Organization (WHO) recommended level. The binuclear Cu2+and Co2+complexes of the receptors have been also prepared and characterized using spectroscopic methods and MALDI-TOF mass analysis. Furthermore, the binding stoichiometry between the receptors upon the addition Cu2+and Co2+has been investigated using Job's plot. Moreover, the fluorescence emission spectra of the receptors and their metal complexes are also reported.
authors.affiliation: Department of Chemistry, Faculty of Science, Arak University, Arak 38156-8-8349, Iran.
authors.forename: Samira Gholizadeh
authors.initials: SG
authors.lastname: Dogaheh
authors.affiliation: Department of Chemistry, Faculty of Science, Arak University, Arak 38156-8-8349, Iran. Electronic address: h-khanmohammadi@araku.ac.ir.
authors.forename: Hamid
authors.initials: H
authors.lastname: Khanmohammadi
authors.affiliation: Departament de Quimica Inorganica i Orgànica, Secció de Química Inorgànica, i Institut de Nanociencia i Nanotecnologia, Universitat de Barcelona, Av Diagonal 645, 08028 Barcelona, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Carolina Sañudo
keywords: Azo-azomethine receptor; Chemosensor; Crystal structure; Fluorescence emission spectra; Naked-eye detection