A simple urea-based multianalyte and multichannel chemosensor for the selective detection of F-, Hg2+ and Cu2+ in solution and cells and the extraction of Hg2+ and Cu2+ from real water sources: a logic gate mimic ensemble.

Herein, a hydrazine-based chromogenic, fluorogenic and electrochemical chemosensor BCC [1,5-bis(4-cyanophenyl) carbonohydrazide] was premeditated and synthesized through a simple one-step synthetic procedure for the selective detection of toxic anions, such as F-, in a DMSO-ACN medium and cations, such as Hg2+ and Cu2+, in a MeOH-water medium. The detection limit for F- was reckoned to be 0.5 ppm, and for Hg2+ and Cu2+, it was 0.8 ppm and 50 nM, respectively. The chemosensor exhibited a distinct change in colour from colourless to dark blue in the presence of F-, and upon the addition of Hg2+ and Cu2+, the BCC turned from colourless to light blue and purple accordingly. Moreover, turn-on fluorescence response transpired by the attenuation of PET signified the selective sensing of analytes with a zero-order rate constant. Sophisticated analytical experiments, such as ESI-MS, UV-Vis, photoluminescence, cyclic voltammetry, FTIR, and 1H-NMR, along with the theoretical calculations corroborated the probable sensing pathways. The reversible colorimetric response of BCC towards F- and H+ can be advantageous in the design of electronic circuits derived from Boolean algebra. The complexation ability of the sensor with toxic Hg2+- and Cu2+-like ions made it an efficient material to remove these metal ions from real water sources polluted with these toxic elemental ions. Furthermore, the in vitro studies were accomplished using the Bauhinia acuminate pollen cell to check the cell penetrability of the sensor molecule.

Hydrazine functionalized probes for chromogenic and fluorescent ratiometric sensing of pH and F-: experimental and DFT studies.

Two novel hydrazine based sensors, BPPIH (N1,N3-bis(perfluorophenyl)isophthalohydrazide) and BPBIH (N1',N3'-bis(perfluorobenzylidene)isophthalohydrazide), are presented here. BPPIH is found to be a highly sensitive pH sensor in the pH range 5.0 to 10.0 in a DMSO-water solvent mixture with a pKa value of 9.22. Interesting optical responses have been observed for BPPIH in the above mentioned pH range. BPBIH on the other hand turns out to be a less effective pH sensor in the above mentioned pH range. The increase in fluorescence intensity at a lower pH for BPPIH was explained by using density functional theory. The ability of BPPIH to monitor the pH changes inside cancer cells is a useful application of the sensor as a functional material. In addition fluoride (F-) selectivity studies of these two chemosensors have been performed and show that between them, BPBIH shows greater selectivity towards F-. The interaction energy calculated from the DFT-D3 supports the experimental findings. The pH sensor (BPPIH) can be further interfaced with suitable circuitry interfaced with desired programming for ease of access and enhancement of practical applications.