Fluorescence sensing of anions

Fluorescence Sensing of Anions, p. 566 Guanidium-Based Anion Receptors, p. (575 Halogen Bonding, p. 628 Macrocyclic Synthesis, p. 830 Molecular Squares, Boxes, and Cubes, p. 909 Naked Anion Effect, p. 939 Organometallic Anion Receptors, p. 1006 Rotaxanes and Pseudorotaxanes, p. 1194 Self-Assembly Definition and Kinetic and Thermodynamic Considerations, p. 1248 The Template Effect, p. 1493... 

Nishizawa, S. Kato. Y. Teramae. N. Fluorescence sensing of anions via intramolecular excimer formation in a pyrophosphate-induced self-assembly of a pyrene-functionalized guanidinium receptor. J. Am. Chem. Soc. 1999. 121 (40). 9463-9464. 

Hamilton. A.D. Fluorescent Sensing of Anions. In Encyclopedia of Supramolecular Chemistry, Atwood, J.L., Steed. J.W., Eds. Dekker, 2002. 

Biosensors, p. 115 DNA Nanotechnology, p. 475 Fluorescence Sensing of Anions, p. 566 Fluorescent Sensors, p. 572 Imaging and Targeting, p. 687 Luminescent Materials, p. 875 Photochemical Sensors, p. 1053 Supramolecular Photnchernistn, p. 1434... 

Fluorescence Sensing of Anions, p. 566 Fluorescent Sensors, p. 572 Luminescent Probes, p. 821... 

Amide- and Urea-Based Anion Receptors, p. 51 Amino Acids Applications, p. 42 Chiral Guest Recognition, p. 236 Deoxycholic, Cholic, and Apocholic Acids, p. 441 Fluorescence Sensing of Anions, p. 566 Guanidinium-Based Anion Receptors, p. 615 Hydrogen Bonding, p. 658 lonophores, p. 760... 

For the reaction-based sensing of anions, the most considerable success has been reached in cyanide sensing, basically due to the necessity for assessing this toxic species and because it can be easily addressed in water due to its high nucleophi-licity. For instance, the coumarin derivative 50 shows a dramatic fluorescence increase after cyanide-induced cyanohydrin reaction (Fig. 19), no response to... 

Since coordinatively unsaturated Zn polyamine complexes display a good affinity towards the COO group, the [Zn (42)] + platform was first tested for fluorescent sensing of carboxylate anions. For instance, there is evidence from spec-trophotometric titration experiments that [Zn (42)] + forms a stable adduct with benzoate, in ethanolic solution at 25 °C. However, even after the addition of a large excess of benzoate to an ethanolic solution of [Zn (42)] +, the typical fluorescent emission of the anthracene fragment is not altered at all. Quite interestingly, when a solution of [Zn (42)] " is titrated with the 4-A,JV-dimethylamine-benzoate anion, the anthracene emission is progressively quenched the fluorescence intensity, Ip, versus anion equivalents profile corresponds to the formation of a T. 1 adduct, and... 

Fig. 7 a Schematic representation for the monolayers of the anion-sensing library, b Relative fluorescence intensity of surfaces modified with different fluorophores and chemical functionalities in the presence of 1CT4 M solutions of HS04", NC>3", TbPCTf and AcCT as tetrabutylammonium salts in acetonitrile. The data have been normalized in the absence of anions the fluorescence emission at 585 and 575 nm for layers LO, L5-L8 and T0-T4, respectively, is set to 0... 

The anthracenylmethyl lariat ether shown as (10) was reported by de Silva and coworkers (1986) as a crown that is useful for fluorescence sensing. Binding of K+ resulted in a detectable fluorescence emission signal. Recent advances in this area include the development of compounds that can sense ion pairs. The anthracenyl crown shown as (11) was designed to simultaneously sense sodium and phosphate ions (de Silva, 2003). Excitation of the complex with ultraviolet radiation results in a fluorescent output only when Na+ is complexed in the crown and the ammonium groups are bound to the anion. The complex self-quenches in the case when either no or only one of the ions is present. 

Recently, Czamik et al. have reported the use of the acyclic protonated amine host 9 as a chemosensor of pyrophosphate. Typical fluorescence sensing methods rely on the ability of a complexed anion to quench the fluorophore. The fluorescence intensity of host 9, however, is actually increased upon complexation of anions and its 2200-fold selectivity of pyrophosphate over phosphate allows for real-time assay of pyrophosphate hydrolysis by inorganic pyrophosphatase.18... 

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