The combined influence of surface modification, size distribution, and interaction time on the cytotoxicity of CdTe quantum dots in PANC-1 cells.

Mercaptopropionic acid (MPA) and cysteamine (Cys) capped CdTe quantum dots (QDs) were successfully prepared and used to investigate the combined influence of surface modification, size distribution, and interaction time on their cytotoxicity in human pancreatic carcinoma (PANC-1) cells. Results indicated that the smaller the size of MPA-CdTe QDs, the higher the cytotoxicity, which could be partly due to the difference of their distribution inside cells. Comparing with MPA-CdTe QDs, Cys-CdTe QDs had better cellular metabolizability and lower cytotoxicity. These QDs' cellular distribution and cytotoxicity were closely related to their interaction time with cells. Their cytotoxicity was found to be significantly enhanced with the increase of incubation time in medium. After QD treatments, the influence of recover time on the final cell viability was also dependent on the concentration and surface modification of QDs used in pretreatment. The combined influence of these factors discussed here might provide useful information for understanding and reducing the cytotoxicity of QDs in future biomedical applications.