title: A selective, sensitive, colorimetric, and fluorescence probe for relay recognition of fluoride and Cu(II) ions with "off-on-off" switching in ethanol-water solution.
abstract: Anion to cation relay recognition was designed and realized for the first time with sequence specificity (F(-)→Cu(2+)) via a fluorescence "off-on-off" mechanism. Probe 1 was a highly selective, sensitive, and turn-on chemodosimeter for F(-) through a specific cyclization reaction triggered by the strong affinity of fluoride toward silicon with a significant change of fluorescence color in both ethanol and ethanol-water (1:1, v/v) solution. Fluorescence enhancement factors were dramatic: 833-fold in ethanol and 164-fold in ethanol-water (1:1, v/v) solution, respectively. The in situ system generated from the sensing of F(-) showed good relay recognition ability for Cu(2+) via fast fluorescence quenching by the formation of a 1:1 complex in ethanol-water (1:1, v/v) solution. The isolated pure compound 2 also exhibited high selectivity toward Cu(2+) in PBS buffer (pH = 7.0) solution. The origin of this sequence specificity of fluorescence recognition was disclosed through the crystal or optimized structures and DFT calculations of corresponding compounds.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, People's Republic of China. pengyu@lzu.edu.cn
authors.forename: Yu
authors.initials: Y
authors.lastname: Peng
authors.forename: Yu-Man
authors.initials: YM
authors.lastname: Dong
authors.forename: Ming
authors.initials: M
authors.lastname: Dong
authors.forename: Ya-Wen
authors.initials: YW
authors.lastname: Wang
mesh_terms: D003124:Colorimetry; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D000431:Ethanol / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry; D011789:Quantum Theory; D012996:Solutions; D014867:Water / Q000737:chemistry*
chemical_list: D005456:Fluorescent Dyes; D007477:Ions; D009942:Organometallic Compounds; D012996:Solutions; D014867:Water; D000431:Ethanol; D003300:Copper; D005459:Fluorides