Ratiometric, Reversible, and Parts per Billion Level Detection of Multiple Toxic Transition Metal Ions Using a Single Probe in Micellar Media

Abstract

We present the selective sensing of multiple transition metal ions in water using a synthetic single probe. The probe is made up of pyrene and pyridine as signaling and interacting moiety, respectively. The sensor showed different responses toward metal ions just by varying the medium of detection. In organic solvent (acetonitrile), the probe showed selective detection of Hg2+ ion. In water, the fluorescence quenching was observed with three metal ions, Cu2+, Hg2+, and Ni2+. Further, just by varying the surface charge on the micellar aggregates, the probe could detect and discriminate the above-mentioned three different toxic metal ions appropriately. In neutral micelles (Brij 58), the probe showed a selective interaction with Hg2+ ion as observed in acetonitrile medium. However, in anionic micellar medium (sodium dodecyl sulfate, SDS), the probe showed changes with both Cu2+ and Ni2+ under UV-vis absorption spectroscopy. The discrimination between these two ions was achieved by recording their emission spectra, where it showed selective quenching with Cu2+.

Addressing of multiple-metal ions on a single platform

“…Combining pyrene and pyridine together as signaling and interacting units respectively, Kumari et al [74] reported a single probe 45 for differential sensing of more than one transition metal ions at parts per billion levels. The probe could recognize Hg 2+ in acetonitrile as well as in neutral micellar medium (Brij-58) by showing Fig.…”

“…46. Structure of probe 45 which shows dual-channel sensing behavior toward Hg 2+ , Cu 2+ and Ni 2+ ions in differently charged micellar medium [74]. fluorescence quenching behavior.…”

Tetrasubstituted imidazole core containing ESIPT fluorescent chemodosimeter for selective detection of cyanide in different medium

“…Moreover, we also studied the photophysical behavior of 3 and its selectivity for CN -in the neutral, cationic and anionic surfactant micellar medium. In fact, micelles in a simple model, mimic the membranes of biosystems [47,48] and is expected to modify and/or improve photophysical/photochemical processes due to a change in the micropolarity, surface charges and rigidity inside the micellar microenvironments [45,46]. Interestingly, when the emission spectra were acquired in the presence of SDS, CTAB and Triton (concentration above CMC) probe 3 showed relatively better emission behavior in Triton and also could able to detect CN -selectively, through enhanced emission (Supporting information; Figure S36).…”

A new ferrocene–anthracene dyad for dual-signaling sensing of Cu(II) and Hg(II)

“…Today, different types of fluorescent receptors are known for the sensing of Hg 2+ and Cu 2+ [15][16][17][18][19][20]. However, they often show fluorescence quenching (turn-off) response.…”