Toxicity and biodistribution of aqueous synthesized ZnS and ZnO quantum dots in mice

Abstract

In the present study, ZnS and ZnO quantum dots (QDs) were synthesized via an all-aqueous process with polyethylene glycol (PEG) chains on their surface, and their toxicity as well as biodistribution were evaluated. No haemolysis occurred at a high concentration of 1600 µg/mL in vitro haemolytic assay, which demonstrated that the QDs-PEG displayed good blood compatibility. Following intravenous administration at 2, 6, and 20 mg/kg of the QDs-PEG in mice, the biodistribution, excretion and biocompatibility were characterized at 1 h, 24 h and 7 days, respectively. Quantitative analysis results indicated that the biodistribution trend of ZnS QDs-PEG was similar to that of ZnO QDs-PEG. The QDs-PEG were mainly trapped in the lung and liver, and almost removed from blood within 1 h. QDs-PEG were primarily excreted in faeces at the 2 and 6 mg/kg doses. Coefficients, haematology, blood biochemistry and histopathology results indicated that the QDs-PEG were safe and biocompatible.

Hepatotoxicity assessment of Mn-doped ZnS quantum dots after repeated administration in mice

“…Additionally, our previous study found that ZnS and ZnO QDs were both mainly located in the liver after intravenous injection. 29 The accumulation and metabolism of QDs may cause toxic and other unwanted effects on liver tissue.…”

“…This result is in accordance with our previous report that ZnS QDs did not cause noticeable toxicity in mice. 29 The levels of serum aminotransferases (ALT and AST) correspond well with the extent of liver cell damage and are commonly used as indicators of liver function. In liver cells, ALT is mainly found in the cytoplasm and is sensitive to acute hepatocyte injury induced by drugs or alcohol.…”

Toxicity of quantum dots on respiratory system

“…Some previous evidence also indicated that PEG capped QDs presented good blood compatibility, and tended to attenuate the toxicity of uncoated QDs with different core/ shell materials by inhibiting ROS generation Zhang et al, 2013). However, Ho et al (2013) suggested that PEG coatings failed to prevent adverse responses caused by administration of QDs via the lung, where they were mainly trapped in the lung and needed a few time to be removed (Yang et al, 2013). Otherwise, PEG is still useful for minimizing the toxicity of other nanoparticles (Ju et al, 2013).…”

Revisiting 30 years of biofunctionalization and surface chemistry of inorganic nanoparticles for nanomedicine

“…PEGylated QDs have also been successfully produced for effective in vitro and in vivo circulation (Skaff and Emrick, 2003; Hu et al, 2010; Prow et al, 2012; Yang et al, 2012b). Recently, Poulose et al developed highly biocompatible PEG functionalized in cadmium chalcogenide luminescent QDs (CdS, CdSe, and CdTe) as an imaging tool for early diagnosis of cancer by targeting a cancer cell line (Poulose et al, 2012).…”