title: A Zn(2+)-responsive highly sensitive fluorescent probe and 1D coordination polymer based on a coumarin platform.
abstract: A coumarin-based Schiff base (receptor 1) exhibited fluorescence enhancement selectively with Zn(2+) at a nanomolar level in near-aqueous medium (EtOH-H2O; 1:1, v/v). The response was instantaneous with a detection limit of 3.26 × 10(-9) M. The sensing event is supposed to incorporate a combinational effect of intramolecular charge transfer (ICT), chelation-enhanced fluorescence (CHEF) and C[double bond, length as m-dash]N isomerization mechanisms. Various spectroscopic methods, viz. IR, UV-visible, fluorescence and NMR in association with single crystal XRD studies, were used for thorough investigation of the structure of receptor 1 as well as of the sensing event. The Zn(2+) complex of receptor 1 exhibited a very nice 1D chain coordination polymeric framework in its single crystal XRD.
authors.affiliation: Department of Chemistry (Centre of Advanced Study), Faculty of Science, Banaras Hindu University, Varanasi-221005, India. drkaushalbhu@yahoo.co.in.
authors.forename: Virendra
authors.initials: V
authors.lastname: Kumar
authors.forename: Ajit
authors.initials: A
authors.lastname: Kumar
authors.forename: Uzra
authors.initials: U
authors.lastname: Diwan
authors.forename: K K
authors.initials: KK
authors.lastname: Upadhyay