The cytotoxicity of cadmium based, aqueous phase - synthesized, quantum dots and its modulation by surface coating.
In this report, we evaluated the cytotoxicity of a series of quantum dots (QDs) directly synthesized in aqueous phase, i.e., thiols-stabilized CdTe, CdTe/CdS core-shell structured and CdTe/CdS/ZnS core-shell-shell structured QDs, with a variety of cell lines including K562 and HEK293T. We have demonstrated that the CdTe QDs are highly toxic for cells due to the release of cadmium ions. Epitaxial growth of a CdS layer reduces the cytotoxicity of QDs to a small extent. However, the presence of a ZnS outlayer greatly improves the biocompatibility of QDs, with no observed cytotoxicity even at very high concentration and long-time exposure in cells. Our systematic investigation clearly shows that the cytotoxicity of QDs can be modulated through elaborate surface coatings and that the CdTe/CdS/ZnS core-shell-shell structured QDs directly synthesized in aqueous phase are highly promising biological fluorescent probes for cellular imaging.
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jialuo Road 2019, Shanghai 201800, China.
Yuanyuan
Y
Su
Yao
Y
He
Haoting
H
Lu
Liman
L
Sai
Qingnuan
Q
Li
Wenxin
W
Li
Lianhui
L
Wang
Pingping
P
Shen
Qing
Q
Huang
Chunhai
C
Fan
D019187:Cadmium Compounds / Q000494:pharmacology*; D016923:Cell Death / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D020014:K562 Cells; D045663:Quantum Dots; D013438:Sulfhydryl Compounds / Q000378:metabolism; D013440:Sulfides / Q000494:pharmacology*; D013499:Surface Properties / Q000187:drug effects; D013691:Tellurium / Q000494:pharmacology*; D014867:Water / Q000737:chemistry*; D017967:Zinc Compounds / Q000494:pharmacology
D019187:Cadmium Compounds; D013438:Sulfhydryl Compounds; D013440:Sulfides; D017967:Zinc Compounds; C034939:cadmium sulfide; D014867:Water; C031238:zinc sulfide; D013691:Tellurium; C028337:cadmium telluride