A Novel Cobalt-Sensitive Fluorescent Chemosensor Based on Ligand Capped CdS Quantum Dots
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Updated: Apr 15, 2026
Compact Quantum Dots for Single-molecule Imaging
Published on: October 9, 2012
Farnoush Faridbod1, Abbas Jamali, Mohammad Reza Ganjali
1Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran, Iran, faridbodf@khayam.ut.ac.ir.
Abstract:
In this work, a ligand capped CdS QDs was synthesized, characterized and its fluorescence behavior was studied. The surface of the CdS QDs was modified using N-(3-methyl-2-(thiophene-2-carboxamido) phenyl) thiophene-2-carboxamide. The immobilized ligand on the surface of the CdS QDs can interact by cationic species due to the existence of donating atoms in its structures. Thus, effect of some metal cations on the fluorescent intensity of the ligand capped CdS QDs were studied. It was found that fluorescence intensity of the modified CdS QDs quenched selectively by addition of Co(II) ion in comparison with other cations tested. The ligand capped CdS QDs can be used as a fluorescent bulk chemosensor for detection of Co(II) ions. The fluorescent quenching is linear in the range of 1.0 × 10(-5) to 1.5 × 10(-4) mol L(-1) of Co(II) ions. The limit of detection was obtained 8.3 × 10(-7) mol L(-1). The nanosensor exhibits high selectivity toward Co(II) ions in comparison with common metal ions.
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