Glutathione Capped CdSe Quantum Dots: Synthesis, Characterization, Morphology, and Application as a Sensor for Toxic Metal Ions

Glutathione (GSH) functionalized CdSe quantum dots (QDs) (GSH-f-CdSe QDs) were prepared via a simple one-pot strategy at low temperature. The as-synthesized CdSe QDs were characterized by FT-IR and XPS analyses. The morphology, physical structure and size distribution of GSH-f-CdSe QDs were investigated by TEM, XRD and DLS analyses, respectively. The GSH-f-CdSe QDs exhibited excellent stability of optical properties as investigated by UV-Vis absorption and photoluminescence (PL) spectroscopy. The high affinity of GSH towards heavy metal ions made the GSH-f-CdSe QDs quite susceptible to Pb2+ ion which poses serious threat to the health and environment. The PL intensity of GSH-f-CdSe QDs was observed to be apparently quenched in the presence of Pb2+ ions in aqueous solution rendering their potentialities as a sensor for detection of toxic heavy metal ions.