title: Design and synthesis of an on-off "click" fluorophore that executes a logic operation and detects heavy and transition metal ions in water and living cells.
abstract: We have designed and synthesized a novel fluorescent molecular probe using the Cu(i)-catalyzed Huisgen cycloaddition of 1,3-diethynyl-6-fluoroisoquinoline with 1-(2-azidoethyl)pyrrolidine. This water soluble "click" fluorescent chemosensor displays good sensitivity towards heavy and transition metal ions. It shows pronounced fluorescence enhancement and high selectivity for Zn(2+) over other biologically relevant metal ions in water at pH 7.0. The fluorescence response of the bis-triazole derivative in the presence of Zn(2+) is switchable and reversible as a function of pH. The chemosensor also exhibits fluorescence quenching with Fe(2+) and Cu(2+) in water at pH 7.0. A modified YES logic gate property has been proposed using the "turn-on" and "turn-off" behavior of the bis-triazole with Zn(2+) and Fe(2+). The sensor is cell membrane permeable and applicable for intracellular Zn(2+) imaging.
authors.affiliation: Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032, India.
authors.forename: Ganesh Chandra
authors.initials: GC
authors.lastname: Midya
authors.forename: Sushovan
authors.initials: S
authors.lastname: Paladhi
authors.forename: Sudipta
authors.initials: S
authors.lastname: Bhowmik
authors.forename: Subhadeep
authors.initials: S
authors.lastname: Saha
authors.forename: Jyotirmayee
authors.initials: J
authors.lastname: Dash
mesh_terms: D045744:Cell Line, Tumor; D003300:Copper / Q000737:chemistry; D005456:Fluorescent Dyes / Q000138:chemical synthesis* / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000032:analysis; D019216:Metals, Heavy / Q000737:chemistry*; D018613:Microscopy, Confocal; D028561:Transition Elements / Q000032:analysis*; D014867:Water / Q000737:chemistry; D015032:Zinc / Q000032:analysis
chemical_list: D005456:Fluorescent Dyes; D019216:Metals, Heavy; D028561:Transition Elements; D014867:Water; D003300:Copper; D007501:Iron; D015032:Zinc