Fluorescent Sensor for Copper(II) and Cyanide Ions via the Complexation-Decomplexation Mechanism with Di(bissulfonamido)spirobifluorene.

A novel spirobifluorene derivative bearing two bissulfonamido groups is successfully synthesized by Sonogashira coupling. This compound exhibits a strong fluorescence quenching by Cu(II) ion in a 50% mixture between acetonitrile and 20 mM pH 7.0 -(2-hydroxyethyl)piperazine-'-ethanesulfonic acid (HEPES) buffer with a detection limit of 98.

Novel sulfonamidospirobifluorenes as fluorescent sensors for mercury(ii) ion and glutathione.

Novel spirobifluorene derivatives containing two and four sulfonamide groups are successfully synthesized from the commercially available bromo-9,9'-spirobifluorene by Sonogashira couplings. These compounds exhibit an excellent selective fluorescence quenching by Hg(ii) in DMSO/HEPES buffer mixture with three-times-noise detection limits of 10.4 to 103.

Hydrophilic Truxene Derivative as a Fluorescent off-on Sensor for Copper (II) Ion and Phosphate Species.

A new symmetrical truxene derivative (TP3) containing three dipicolylamino peripheral groups is successfully synthesized in four synthetic steps with an overall yield of 42%. This hydrophilic fluorescent compound exhibits a maximum absorption wavelength at 375 nm, an emission maximum at 474 nm with an outstanding 58% quantum efficiency in THF-HEPES buffer mixture. The compound shows a highly selective fluorescence quenching towards Cu(II) ion with a detection limit of 0.