Supramolecular hybrid of ZnO nanoparticles with benzimidazole based organic ligand for the recognition of Zn2+ ions in semi-aqueous media

Abstract

Zinc oxide (ZnO) nanoparticles were decorated with benzimidazole based organic ligand (L) to form supramolecular hybrid for the recognition of Zn2+ in HEPES-buffered DMSO/H2O (7:3; v/v) solvent media using absorption spectroscopy. The resultant hybrid compound (N) showed the shifting of imine linkage bands ( CH¼N ) in IR spectra due to the chemical attachment of organic ligand (L) on ZnO surface. The coating of organic ligand on the surface of ZnO was also confirmed with energy-dispersive x-ray (EDX) analysis. The resultant hybrid compound (N) exhibited high selectivity towards Zn2+ ions over other metal ions in HEPES-buffered DMSO/H2O (7:3; v/v) solution. The absorption peak intensity for Zn2+ ions was observed at 560 nm (1 nM), which was quenched by the addition of mole concentration and the peak shifted toward lower wavelength region at 442 nm (50 nM) resulted the development of hybrid chemosensor with a detection limit of 4.09 nM.