A Preliminary Study on Cytotoxicity of CdSe/ZnS-SA Quantum Dots

Objective: To investigate the toxicity of functionalized quantum dots to the HEK293 cells stably transfected with recombinant pcDNA3. 1 / APP595 /596 plasmid. Methods: The HEK293 cell,which was stably transfected with recombinant pcDNA3. 1 / APP595 /596 plasmid,was cultured in the medium containing CdSe / ZnS-SA quantum dots. Cell morphology was evaluated by inverted fluorescence microscope. Cell activity was estimated by 3-( 4,5)-dimethylthiahiazo(-z-yl)-di-phenytetrazoliumromide( MTT) test. Cell apoptosis was analyzed by flow cytometry. Results: Morphological study revealed no obvious deformation of cell,which was cultured with CdSe / ZnS-SA quantum dots in a concentration range of 2. 5 nmol / L-20 nmol / L at 8 h,16 h and 24 h respectively. No statistical differences of absorbance as well as the pencentages of apoptosis were seen between the treatment groups in which cell was cultured with CdSe / ZnS-SA quantum dots in a concentration range of 2. 5 nmol / L-25 nmol / L at 8 h,16 h and 24 h respectively and control group( P 0. 05). Conclusions: In the short term,a certain concentration range( 2. 5 nmol/L ~ 25 nmol/L) of CdSe/ZnSSA quantum dots has no significant cytotoxicity,but good biocompatibility.