Selective Detection of H2S by Copper Complex Embedded in Vesicles through Metal Indicator Displacement Approach.

A new approach for the detection of hydrogen sulfide (H2S) was constructed within vesicles comprising phospholipids and amphiphilic copper complex as receptor. 1,2-Distearoyl- sn-glycero-3-phosphocholine (DSPC) vesicles with embedded metal complex receptor (1.Cu) sites have been prepared. The vesicles selectively respond to H2S in a buffered solution and show colorimetric as well as spectral transformation. Other analytes such as reactive sulfur species, reactive nitrogen species, biological phosphates, and other anions failed to induce changes. The H2S detection is established through a metal indicator displacement (MIDA) process, where Eosin-Y (EY) was employed as an indicator. Fluorescence, UV-vis spectroscopy, and the naked eye as the signal readout studies confirm the high selectivity, sensitivity, and lower detection limit of the vesicular receptor. The application of vesicular receptors for real sample analysis was also confirmed by fluorescence live cell imaging.

Synthesis and spectroscopic characterization of fluorescent 4-aminoantipyrine analogues: Molecular docking and in vitro cytotoxicity studies.

Two substituted aromatic carbonyl compounds (compounds 1 and 2) of 4-aminoantipyrine were synthesized by condensation of fluorine substituted benzoyl chlorides and 4-aminoantipyrine. The structures of synthesized derivatives were established on the basis of UV-Vis, IR, and Mass, (1)H, (13)C NMR and Fluorescence spectroscopy. Both compounds showed significant fluorescence emission and two broad emission bands were observed in the region at 340 nm and 450 nm on excitation at 280 nm. Theoretically to prove that the molecule has anticancer activity against cervical cancer cells, the compounds were analyzed for molecular docking interactions with HPV16-E7 target protein by Glide protocol. Furthermore, 4-aminoantipyrine derivatives were evaluated for their in vitro cytotoxic activity against human cervical cancer cells (SiHa) by MTT assay. Compound 1 showed two fold higher activity (IC50=0.912 µM) over compound 2, and its activity was similar to that of Pazopanib, suggesting that although the two compounds were chemically very similar the difference in substituent on the phenyl moiety caused changes in properties.