title: In vivo quantum-dot toxicity assessment.
abstract: Quantum dots have potential in biomedical applications, but concerns persist about their safety. Most toxicology data is derived from in vitro studies and may not reflect in vivo responses. Here, an initial systematic animal toxicity study of CdSe-ZnS core-shell quantum dots in healthy Sprague-Dawley rats is presented. Biodistribution, animal survival, animal mass, hematology, clinical biochemistry, and organ histology are characterized at different concentrations (2.5-15.0 nmol) over short-term (<7 days) and long-term (>80 days) periods. The results show that the quantum dot formulations do not cause appreciable toxicity even after their breakdown in vivo over time. To generalize the toxicity of quantum dots in vivo, further investigations are still required. Some of these investigations include the evaluation of quantum dot composition (e.g., PbS versus CdS), surface chemistry (e.g., functionalization with amines versus carboxylic acids), size (e.g., 2 versus 6 nm), and shape (e.g., spheres versus rods), as well as the effect of contaminants and their byproducts on biodistribution behavior and toxicity. Combining the results from all of these studies will eventually lead to a conclusion regarding the issue of quantum dot toxicity.
authors.affiliation: Institute of Biomaterials and Biomedical Engineering, Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, 160 College Street, 4th floor, Toronto, ON M5S3E1, Canada.
authors.forename: Tanya S
authors.initials: TS
authors.lastname: Hauck
authors.forename: Robin E
authors.initials: RE
authors.lastname: Anderson
authors.forename: Hans C
authors.initials: HC
authors.lastname: Fischer
authors.forename: Susan
authors.initials: S
authors.lastname: Newbigging
authors.forename: Warren C W
authors.initials: WC
authors.lastname: Chan
mesh_terms: D000818:Animals; D019187:Cadmium Compounds / Q000493:pharmacokinetics* / Q000633:toxicity*; D008422:Materials Testing; D008657:Metabolic Clearance Rate; D009928:Organ Specificity; D045663:Quantum Dots; D051381:Rats; D017207:Rats, Sprague-Dawley; D012643:Selenium / Q000493:pharmacokinetics* / Q000633:toxicity*; D018036:Selenium Compounds / Q000493:pharmacokinetics* / Q000633:toxicity*; D013440:Sulfides; D014018:Tissue Distribution
chemical_list: D019187:Cadmium Compounds; D018036:Selenium Compounds; D013440:Sulfides; C058667:cadmium selenide; D012643:Selenium