Biodistribution, pharmacokinetics and toxicology of Ag2S near-infrared quantum dots in mice

Biomaterials. 2013 May;34(14):3639-46. doi: 10.1016/j.biomaterials.2013.01.089. Epub 2013 Feb 14.


Ag2S quantum dots (QDs) have been demonstrated as a promising near-infrared II (NIR-II, 1.0-1.4 μm) emitting nanoprobe for in vivo imaging and detection. In this work, we carefully study the long-term in vivo biodistribution of Ag2S QDs functionalized with polyethylene glycol (PEG) and systematically examine the potential toxicity of Ag2S QDs over time. Our results show that PEGylated-Ag2S QDs are mainly accumulated in the reticuloendothelial system (RES) including liver and spleen after intravenous administration and can be gradually cleared, mostly by fecal excretion. PEGylated-Ag2S QDs do not cause appreciable toxicity at our tested doses (15 and 30 mg/kg) to the treated mice over a period of 2 months as evidenced by blood biochemistry, hematological analysis and histological examinations. Our work lays a solid foundation for further biomedical applications of Ag2S QDs as an important in vivo imaging agent in the NIR-II region.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Female
  • Mice
  • Mice, Inbred BALB C
  • Polyethylene Glycols / chemistry
  • Quantum Dots*
  • Silver Compounds / chemistry*
  • Silver Compounds / pharmacokinetics
  • Spectroscopy, Near-Infrared


  • Silver Compounds
  • Polyethylene Glycols
  • silver sulfide