水相合成CdX (X＝Te, Te/CdS, Te/ZnS)红色量子点及毒性效应

分别以巯基乙酸(Mercaptoacetic Acid, MA)、还原型谷胱甘肽(Glutathione, GSH)为稳定剂在水相中直接合成了巯基乙酸CdTe (CdTe-MA)、红色巯基乙酸CdTe/CdS (CdTe/CdS-MA)、巯基乙酸CdTe/ZnS (CdTe/ZnS-MA)及谷胱甘肽CdTe (CdTe-GSH)量子点. 其中, CdTe-GSH量子点的量子产率可达47.3%. 体外溶血实验证实CdTe/ZnS-MA和CdTe-GSH量子点的溶血率较CdTe-MA和CdTe/CdS-MA低, 浓度为0.05 mmol/L的量子点溶血率＜5%, 达到了生物医用材料的要求. 活体实验证实: 通过尾静脉方式把量子点注入小鼠体内后, 荧光显微镜观察发现高剂量的量子点(0.4 mmol/10 g)在体内主要在心、肝、脾、肾组织中分布较多, 且引起不同程度的组织病变.

Aqueous Phase Synthesis of Red CdX (X=Te,Te/CdS,Te/ZnS) Quantum Dots and Their Toxic Effects

Mercaptoacetic acid (MA) capped CdTe, CdTe/CdS, CdTe/ZnS quantum dots (QD) and glutathione (GSH)-capped CdTe QDs were directly synthesized in aqueous media. The fabricated CdTe-GSH QDs have an ultra small hydrodynamic diameter (3～4 nm) and possess high quantum yields (47.3%). In vitro hemolysis testing showed that the hemolysis rates (HR) of CdTe/ZnS-MA and CdTe-GSH were less than 5% (concentration being 0.05 mmol/L), which were lower than CdTe-MA and CdTe/CdS-MA QDs, meeting the requirements for biomedical materials. The toxicity of QD in vivo was tested by injected QD in mice through tail vein. Fluorescence microscopy showed that a high dosage (0.4 mmol/10 g) of CdTe-GSH and CdTe/ZnS-MA QD was distributed mainly in the heart, liver, spleen and kidney tissues and caused varying degrees of tissue lesions.