In situ synthesis of highly luminescent glutathione-capped CdTe/ZnS quantum dots with biocompatibility.
This paper focuses on the in situ synthesis of novel CdTe/ZnS core-shell quantum dots (QDs) in aqueous solution. Glutathione (GSH) was used as both capping reagent and sulfur source for in situ growth of ZnS shell on the CdTe core QDs. The maximum emission wavelengths of the prepared CdTe/ZnS QDs can be simply tuned from 569 nm to 630 nm. The PL quantum yield of CdTe/ZnS QDs synthesized is up to 84%, larger than the original CdTe QDs by around 1.7 times. The PL lifetime results reveal a triexponential decay model of exciton and trap radiation behavior. The average exciton lifetime at room temperature is 17.1 ns for CdTe (2.8 nm) and 27.4 ns for CdTe/ZnS (3.7 nm), respectively. When the solution of QDs is dialyzed for 3 h, 1.17 ppm of Cd(2+) is released from CdTe QDs and 0.35 ppm is released from CdTe/ZnS. At the dose of 120 microg/ml QDs, 9.5% of hemolysis was induced by CdTe QDs and 3.9% was induced by CdTe/ZnS QDs. These results indicate that the synthesized glutathione-capped CdTe/ZnS QDs are of less toxicity and better biocompatibility, so that are attractive for use in biological detection and related fields.
Liu
Ying-Fan
YF
Key Lab of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China.
Yu
Jun-Sheng
JS
D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry; D019187:Cadmium Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D005978:Glutathione / Q000737:chemistry*; D049449:Luminescence; D010316:Particle Size; D045663:Quantum Dots; D013440:Sulfides / Q000138:chemical synthesis* / Q000737:chemistry; D013499:Surface Properties; D013691:Tellurium / Q000737:chemistry; D017967:Zinc Compounds / Q000138:chemical synthesis* / Q000737:chemistry
D001672:Biocompatible Materials; D019187:Cadmium Compounds; D013440:Sulfides; D017967:Zinc Compounds; D005978:Glutathione; C031238:zinc sulfide; D013691:Tellurium; C028337:cadmium telluride