title: "Off-on" aggregation-based fluorescent sensor for the detection of chloride in water.
abstract: Receptors selective for anions in aqueous media are a crucial component in the detection of anions for biological and environmental applications. Recent sensor designs have taken advantage of systems known to aggregate in solution, eliciting a fluorescent response. Herein, we demonstrate a chloride-selective fluorescent response of receptor 1(+), based on our well-established class of 2,6-bis(2-anilinoethynyl)pyridine bisureas. The fluorescence intensity ratio of 1(+)·Cl(->) aggregates in water is four times larger than the next most fluorescent anion complex, 1(+)·ClO4(->). In addition, (1)H NMR spectroscopic titrations demonstrate 1(+) binds chloride more strongly than other biologically relevant anions in solutions of both DMSO-d6 and 50/50 DMSO-d6/MeCN-d3.
authors.affiliation: Department of Chemistry & Biochemistry and Materials Science Institute, University of Oregon, Eugene, OR 97403-1253, USA. dwj@uoregon.edu haley@uoregon.edu.
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Watt
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Engle
authors.forename: Kurtis C
authors.initials: KC
authors.lastname: Fairley
authors.forename: Timothy E
authors.initials: TE
authors.lastname: Robitshek
authors.forename: Michael M
authors.initials: MM
authors.lastname: Haley
authors.forename: Darren W
authors.initials: DW
authors.lastname: Johnson
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D002712:Chlorides / Q000032:analysis* / Q000737:chemistry; D008968:Molecular Conformation; D013050:Spectrometry, Fluorescence; D014867:Water / Q000737:chemistry*
chemical_list: D002712:Chlorides; D014867:Water