Designing of thiosemicarbazone-triazole linked organotriethoxysilane as UV-Visible and fluorescence sensor for the selective detection of Hg2+ ions and their cytotoxic evaluation

Abstract

In this manuscript, a new series of thiosemicarbazone-triazole linked organotriethoxysilanes (6a-6 g) have been synthesized using Cu (I) catalyzed click reaction and characterized by spectroscopic techniques including IR, 1H and 13C NMR, TGA and ESI-QTOF mass spectrometry. The compound 6a was screened for its photophysical properties using UV-Visible and fluorescence spectroscopy which showed the selective detection of Hg2+ ion without any significant interference from different metal cations. The chemosensor 6a binds in 1:1 stoichiometry with Hg2+ confirmed by Job's-plot and with high binding affinity as determined from association constant values 0.3747 × 106 M−1 and 0.3134 × 107 M−1 obtained from BH-plot and Stern-Volmer plot respectively. The LOD values for Hg2+ obtained from absorption and emission spectroscopy were 0.3122 × 10−6 M and 0.3928 × 10−7 M respectively. The binding interactions between 6a and Hg2+ion were also examined by conducting DFT calculations on Gaussian 03 software. Furthermore, all the synthesized organosilanes were tested for their use in the biological field by evaluating their pharmacokinetic profile and cytotoxicity using PreADMET, molinspiration software and PLHC-1 cell line. The chemosensor 6a with lowest cytotoxicity could be applied to monitor Hg2+ ions in living cells.