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.
Su
Yuanyuan
Y
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jialuo Road 2019, Shanghai 201800, China.
He
Yao
Y
Lu
Haoting
H
Sai
Liman
L
Li
Qingnuan
Q
Li
Wenxin
W
Wang
Lianhui
L
Shen
Pingping
P
Huang
Qing
Q
Fan
Chunhai
C
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