Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-27T02:14:36.387Z Has data issue: false hasContentIssue false
  • English
  • Français

Characterization, Imaging and Degradation Studies of Quantum Dots in Aquatic Organisms

Published online by Cambridge University Press:  26 February 2011

Amy H Ringwood ,
Sireesha Khambhammettu ,
Patricia Santiago ,
Emily Bealer ,
Michelle Stogner ,
John Collins  and
Kenneth E Gonsalves
Amy H Ringwood
Affiliation:
[email protected]
Sireesha Khambhammettu
Affiliation:
[email protected], United States
Patricia Santiago
Affiliation:
[email protected]
Emily Bealer
Affiliation:
[email protected]
Michelle Stogner
Affiliation:
[email protected]
John Collins
Affiliation:
[email protected]
Kenneth E Gonsalves
Affiliation:
[email protected]
Get access

Abstract

There are numerous potential environmental risks of engineered nanoparticles that are not yet well-characterized or understood. Nanoparticles may be introduced into aquatic environments during production processes and also as a result of release following their use in electronic and biological applications. The objectives of these studies were to characterize the behavior of quantum dots (QD) in water, and the accumulation of and toxicity to potential biological receptors in aquatic ecosystems. There are natural differences in environmental factors that may affect the degradation rates of QD’s as well as their toxicity, including temperature, salinity, and pH conditions. To assess the responses under different pH conditions, nonfunctionalized QD’s composed of a Cd/Se core surrounded by a ZnS shell (Evident Technologies) were added to distilled water, at pHs of 4, 6, and 8, and the changes in fluorescent emission spectra over time were determined. Likewise, to determine the effects of salinity on degradation rates, QD’s were added to 0.22 filtered seawater samples of different salinities (10, 20, and 30‰). The accumulation and potential toxicity of QD’s were evaluated using hepatopancreas cells of oysters, Crassostrea virginica.

Fluorescent spectroscopy studies with water and cell samples indicated some degradation in low pH and high salinity waters, but did not indicate that there was increased degradation of QD’s accumulated in cells. Fluorescent confocal microscopy verified that QD’s were accumulated into the hepatopancreas cells. Transmission electron microscopy (TEM) studies verified cellular accumulation, and also indicated some limited degradation of the QD’s by the cells over the short time periods (e.g. hours) used in these preliminary studies. Using a lysosomal destabilization assay, there was some evidence of toxicity to hepatopancreatic cells. These kinds of basic studies are essential for characterizing potential cellular toxicity and addressing the potential impacts of nanoengineered particles on aquatic organisms and basic cellular responses.

Keywords

nanoscalebiologicalCd
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 895: Symposium G – Life-Cycle Analysis Tools for “Green” Materials and Process Selection , 2005 , 0895-G04-06-S04-06
Copyright
Copyright © Materials Research Society 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Derfus, A. M., Chan, W. C. W., Bhatia, S. N.. 2004. Probing the cytotoxicity of semiconductor quantum dots. Nano Lett 4:11–18.Google Scholar
2. Shiohara, A., Hoshino, A., Hanaki, K., Suzuki, K., Yamamoto, K.. 2004. On the cyto-toxicity caused by quantum dots. Microbiol. Immunol. 48: 669–675.Google Scholar
3. Masciangioli, T., Zhang, W. X.. 2003. Environmental technologies at the nanoscale. Environ. Science & Technol. 102–108.Google Scholar
4. Warheit, D. B. 2004. Nanoparticles: Health impacts? Materials Today February 2004:32–35.Google Scholar
5. Ringwood, A. H., Conners, D. E., Keppler, C. J., and DiNovo, A. A.. 1999. Biomarker studies with juvenile oysters (Crassostrea virginica) deployed in situ . Biomarkers 4: 400–415.Google Scholar
6. Ringwood, A.H. Conners, D.E., Hoguet, J., and Ringwood, L.A.. 2005. “Lysosomal Destabilization Assays in Estuarine Organisms”, In “Techniques in Aquatic Toxicology, Volume 2”, edited by Ostrander, G. K.. CRC Press, Taylor and Francis, Boca Raton, FL. pp. 287–300.Google Scholar
7. Dubertret, B., Skourides, P., Norris, D. J., Noireaux, V., Brivanlou, A. H., Libchaber, A.. 2002. In vivo imaging of quantum dots encapsulated in phospholipid micelles. Science 298: 1759–1762.Google Scholar
8. Jaiswal, J.K., Simon, S. M.. 2004. Potentials and pitfalls of fluorescent quantum dots for biological imaging. Trends in cell bio 14: 497–504.Google Scholar
9. Kirchner, C., Liedl, T., Kudera, S., Pellegrino, T., Javier, A. M., Gaub, H. E., Stolzle, S., Fertig, N., Parak, W. J.. 2005. Cytotoxicity of colloidal CdSe and Cd/Se/ZnS nanoparticles. Nano Lett. 5: 331–338.Google Scholar