Lung toxicity and biodistribution of Cd/Se-ZnS quantum dots with different surface functional groups after pulmonary exposure in rats

Details

• Alternative Title:
  Part Fibre Toxicol
• Personal Author:
  Roberts, Jenny R ; Antonini, James M ; Porter, Dale W ; Chapman, Rebecca S ; Scabilloni, James F ; Young, Shih-Houng ; Schwegler-Berry, Diane ; Castranova, Vincent ; Mercer, Robert R
• Description:
  Background
  
  The potential use of quantum dots (QD) in biomedical applications, as well as in other systems that take advantage of their unique physiochemical properties, has led to concern regarding their toxicity, potential systemic distribution, and biopersistence. In addition, little is known about workplace exposure to QD in research, manufacturing, or medical settings. The goal of the present study was to assess pulmonary toxicity, clearance, and biodistribution of QD with different functional groups in rats after pulmonary exposure.
  
  Methods
  
  QD were composed of a cadmium-selenide (CdSe) core (~5nm) with a zinc sulfide (ZnS) shell functionalized with carboxyl (QD-COOH) or amine (QD-NH2) terminal groups. Male Sprague–Dawley rats were intratracheally-instilled (IT) with saline, QD-COOH, or QD-NH2 (12.5, 5.0, or 1.25 μg/rat). On days 0, 1, 3, 5, 7, 14, and 28 post-IT, the left lung, lung-associated lymph nodes (LALN), heart, kidneys, spleen, liver, brain, and blood were collected for metal analysis of Cd content by neutron activation to evaluate clearance and biodistribution. One right lobe was ligated and fixed for microscopy and histopathological analysis. The remaining right lobes from rats in each group were subjected to bronchoalveolar lavage (BAL) to retrieve BAL fluid and cells for analysis of injury and inflammation.
  
  Results
  
  Lung injury and inflammation was found to be dose-dependent and peaked at days 7 and 14 post-exposure for both forms of QD, with slight variations in degree of toxicity at early and later time points. Both QD appeared to lose their fluorescent properties and destabilize after 1 week in the lung. Cd persisted up to 28 days for both forms of QD; however, clearance rate was slightly greater for QD-COOH over time. No Cd was detected in the liver, spleen, heart, brain, or blood at any time point. Cd appeared in the LALN and kidneys beginning at 1–2 weeks post-exposure.
  
  Conclusions
  
  QD-COOH and QD-NH2 differed in clearance rate and differed slightly in degree of toxicity at different time points; however, the overall pattern of toxicity and biodistribution was similar between the two particles. Toxicity may be dependent on the dissolution rate and bioavailability of free Cd.
  
  
• Subjects:
  Animals Bronchoalveolar Lavage Fluid Cadmium Cadmium Compounds Dose-Response Relationship, Drug Inhalation Exposure Lung Lung Injury Male Microscopy, Confocal Microscopy, Electron, Transmission Nanoparticles Particle Size Pneumonia Quantum Dots Rats Rats, Sprague-Dawley Research Selenium Compounds Sulfides Surface Properties Tissue Distribution Toxicology Zinc Compounds

  More +
• Source:
  Part Fibre Toxicol. 2013; 10:5.
• Document Type:
  Journal Article
• Volume:
  10
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:2736de17d1f068850cad0cb0a735140b763f71e1ba1a30b347fa22b7bbdad7a8
• Download URL:
  https://stacks.cdc.gov/view/cdc/13264/cdc_13264_DS1.pdf
• File Type:
  [PDF - 2.79 MB ]