A chemosensor for micro- to nano-molar detection of Ag+ and Hg2+ ions in pure aqueous media and its applications in cell imaging

• Published in: Dalton transactions : an international journal of inorganic chemistry 2017-11, Vol.46 (41), p.14201-14209
• Main Authors: Nandre, Jitendra P, Patil, Samadhan R, Sahoo, Suban K, Pradeep, Chullikkattil P, Churakov, Andrei, Yu, Fabiao, Chen, Lingxin, Redshaw, Carl, Patil, Ashok A, Patil, Umesh D
• Format: Article
• Language: English
• ISSN: 1477-9234
• DOI: 10.1039/c7dt02524f

The pyridine substituted thiourea derivative PTB-1 was synthesized and characterized by spectroscopic techniques as well as by single crystal X-ray crystallography. The metal ion sensing ability of PTB-1 was explored by various experimental (naked-eye, UV-Vis, fluorescence, mass spectrometry and 1H NMR spectroscopy) and theoretical (B3LYP/6-31G**/LANL2DZ) methods. PTB-1 exhibited a highly selective naked-eye detectable color change from colorless to dark brown and UV-Vis spectral changes for the detection of Ag+ with a detection limit of 3.67 μM in aqueous medium. The detection of Ag+ ions was achieved by test paper strip and supported silica methods. In contrast, PTB-1 exhibited a 23-fold enhanced emission at 420 nm in the presence of Hg2+ ions with a nano-molar detection limit of 0.69 nM. Finally, the sensor PTB-1 was applied successfully for the intracellular detection of Hg2+ ions in a HepG2 liver cell line, which was monitored by the use of confocal imaging techniques.