A new heteroditopic chemosensor based on the 1,3-alternate conformation of thiacalix[4]crown shows a ratiometric fluorescence response towards Hg(2+) ions. Further, a negative allosteric behaviour between Hg(2+)/Li(+) ions is observed. Thus, metal ion exchange triggers a Hg(2+)/Li(+) switchable fluorescent chemosensor.

A new fluoro-chromogenic chemosensor based on BODIPY-functionalized gold nanoparticles 1 is prepared. Addition of Cu(2+) ions to aqueous solutions of 1 gave an instantaneous color change along with a blue-shift of the absorption band and quenching of the emission spectrum at room temperature. The chemosensor 1 exhibits a high affinity and selectivity for Cu(2+) over competing metal ions tested....

9,10-Anthraquinone-based chemosensor 1 indicates the presence of Cu(II) ions among other transition metal ions with high selectivity by a color change from yellow to dark red. Chemosensor 2 shows binding toward Cu(II), Ni(II) and Co(II) with color changes from yellow to dark red, red and pale green, respectively. Especially, Co(II) binding with chemosensor 2 causes significantly green fluoresce...

Rhodamine B thiolactone is developed as a simple chemosensor towards Hg(2+) in neutral aqueous solution with high selectivity.

A new phosphorescent chemosensor for Hg(2+) and acetonitrile (MeCN) based on iridium(III) complex Ir(dpp)(2)(dtc) (Ir1, dppH = 4,6-diphenylpyrimidine, dtcH = diethyl dithiocarbamic acid) was realized. Upon addition of a tetrahydrofuran (THF) solution of Hg(2+), the dichloromethane (DCM) solution of Ir1 gave a visual color change and significant fluorescent quenching. When MeCN was added, a new ...

8-Hydroxyquinoline derivative 1 as a fluorescent chemosensor for Zn2+ was synthesized. Because Cd2+ is often found with Zn2+ in the environment and can form fluorescent complexes with chelating fluorophores, a potentially important property of chemosensors for Zn2+ is their selectivity for Zn2+ over Cd2+. The Zn2+ or Cd2+ complexes of 1 gave an emission band from the 1:1 complex, but the fluore...

We describe three significant advances in the use of thioureas as reporting elements for metal-responsive fluorescent chemosensors. First, on the basis of the crystal structure of a chemosensor analogue, we provide a deeper understanding of the details of the thiourea coordination environment. Second, we describe a new generation of chemosensors with higher affinities for Zn(2+) and Cd(2+) than...

In order to conveniently and effectively detect the heavy metal ion Hg(2+) existing in water, a magnetic fluorescence chemosensor has been strategically prepared by immobilizing a Rhodamine B derivative RhB-tris(2-aminoethyl)amine on Fe3O4@SiO2-Au@PSiO2 composites via gold particles. The adsorption and detection for Hg(2+) ions were investigated with fluorophotometry. This chemosensor shows hig...

A chromogenic chemosensor for selective pyrophosphate sensing in aqueous environments has been developed using silica functionalised surfaces.

m-Benziporphodimethene is presented here as a long-wavelength Zn2+ specific chemosensor; this sensor shows fluorescence switch-on upon Zn2+ binding with no apparent background fluorescence.