A Ratiometric Green Fluorescent Carbazole-Bis(hydrazinobenzothiazole) Probe for the Selective Detection of Toxic Hg Ions in Real Water Samples.

A dyad Carbazolyl-bis(hydrazinobenzothiazole) was designed to form a symmetrical structure that containing two-arm active binding sites facilitates coordination with Hg ion. This sensor has imparted a colorimetric and fluorometric changes in presence of Hg ions. The ligand showed a selective blue shift in presence of Hgeven in co-existence with heavy metal ions with luminescence change from colorless to blue and colorless to green under day light.

Synthesis of a quinoxaline-hydrazinobenzothiazole based probe-single point detection of Cu, Co, Ni and Hg ions in real water samples.

A novel quinoxaline-hydrazinobenzothiazole based sensor was synthesized and characterized using NMR, FTIR, and Mass spectroscopy techniques. The sensor achieves the distinct "single-point" colorimetric and fluorescent detection of Cu, Co, Ni and Hg ions with distinguishable color changes from yellow to red, pale red, pale brown and orange, respectively. The UV-visible and fluorescence emission spectral investigation revealed the excellent single-point sensing ability of the probe towards four different heavy metal ions with a ratiometric response.

Iminobenzophenone-thiophen hydrazide schiff base: a selective turn on sensor for paramagnetic Fe ion and application in real sample analysis.

A highly selective turn-on sensor for paramagnetic Fe ions based on (E)-N'-((2-aminophenyl)(phenyl)methylene)thiophene-2-carbohydrazide is successfully synthesized. The sensor BPTH is significantly selective and sensitive towards Fe ions over other interfering metal ions especially Cu and Co ions with a lowest limit of recognition 1.48 × 10 M.

Phenothiazine-rhodamine-based colorimetric and fluorogenic 'turn-on' sensor for Zn and bioimaging studies in live cells.

A phenothiazine-rhodamine (PTRH) fluorescent dyad was synthesized and its ability to selectively sense Zn ions in solution and in in vitro cell lines was tested using various techniques. When compared with other competing metal ions, the PTRH probe showed the high selectivity for Zn ions that was supported by electronic and emission spectral analyses. The emission band at 528 nm for the PTRH probe indicated the ring closed form of PTRH, as for Zn ion binding to PTRH, the λ get shift to 608 nm was accompanied by a pale yellow to pink colour (under visible light) and green to pinkish red fluorescence emission (under UV light) due to ring opening of the spirolactam moiety in the PTRH ligand.

A Fluorescent Turn-On Carbazole-Rhodanine Based Sensor for Detection of Ag Ions and Application in Ag Ions Imaging in Cancer Cells.

Carbazole - Rhodanine conjugate is an effective fluorescent host for silver ions through fluorometric transformation from green to red color with a hyperchromic emission. An intramolecular charge transfer process derived from carbazole towards rhodanine favors interaction of thiocarbonyl S and carboxylic acid O of the rhodanine moiety towards Ag ion. Carbazole - rhodanine dyad accomplishes the lowest detection limit of 12.

Carbazole-azine based fluorescence 'off-on' sensor for selective detection of Cu and its live cell imaging.

A new carbazole-azine based fluorescent sensor was synthesized and characterized. The selectivity of the sensor for Cu over other counter ions in a dimethyl sulfoxide/H O mixture was shown through enhancement in fluorescence - an off to on transformation. The specificity of the probe towards Cu was evident in ultraviolet/visible, fluorescence, Fourier transform infrared and mass studies.