One-Pot Aqueous Synthesis and Cell Labeling Application of Glutathione Capped Cu-In-Zn-S Quantum Dots

We report a one-pot method to directly synthesize highly luminescent Cu-In-Zn-S (CIZS) quantum dots (QDs) in aqueous media by using bio-compatible glutathione (GSH) as capping ligand and stabilizer. The influences of various experimental variables, including reaction time, pH value, and precursor ratio, have been systematically investigated. The optical features and structure of the obtained CIZS QDs have been characterized by UV-Vis and fluorescence spectroscopy, transmission electron microscope, powder X-ray diffraction, and FT-IR. As a result, the stable GSH capped CIZS QDs exhibited excellent photoluminescence emission properties, narrow size distribution and excellent biocompatibility under optimum experimental conditions. In addition, as-prepared CIZS QDs were successfully used for fluorescence imaging of MDA-MB-231 cells and emitted bright red fluorescence.