Luminescent Properties and Cytotoxicity of CdTe Quantum Dots with Different Stabilizing Agents

CdTe quantum dots(QDs) were prepared in aqueous phase using thioglycolic acid(TGA),L-cysteine(L-Cys),and glutathione(GSH) as stabilizing agents.The luminescent properties of CdTe QDs with different stabilizing agents were studied by using fluorescence spectra.FTIR spectra analysis demonstrates that CdTe QDs are capped with stabilizing agents through the coordination interaction between Cd2+ and S.Fluorescence spectra show that CdTe QDs with longer emission wavelength(680nm) can be synthesized more easily when L-Cys or GSH is chosen as stabilizing agents and TGA is proper to prepare highly luminescent QDs because of the effect between Cd2+ and sulfhydryl group.The MTT assay and morphology analysis of U87MG cells suggest that the QDs with different stabilizing agents are all toxic to cells.The cytotoxicity of TGA-QDs is higher than that of L-Cys-and GSH-CdTe.The cell viability is only 52.6% when U87MG cells are treated with 20μg/mL of TGA-QDs for 24h.