Using particles that are 1/100,000 the width of a human hair to deliver drugs to cells or assist plants in fighting off pests may sound like something out of a science fiction movie, but these scenarios may be a common occurrence in the near future.
Carbon nanotubes, cylindrically shaped carbon molecules with a diameter of about 1 nanometer, have many potential applications in a variety of fields, such as biomedical engineering and medical chemistry. Proteins, nucleic acids, and drugs can be attached to these nanotubes and delivered to cells and organs. Carbon nanotubes can be used to recognize and fight viruses and other pathogens. However, results of studies in animals have also raised concerns about the potential toxicity of nanoparticles.
Recent research by a team of researchers from China, led by Dr. Nan Yao, explored the effects of nanoparticles on plant cells. The findings of Dr. Yao and his colleagues are published in the October issue of the American Journal of Botany (http://www.amjbot.org/cgi/reprint/97/10/1602).
Dr. Yao and his team of researchers isolated cells from rice as well as from the model plant species Arabidopsis. The researchers treated these cells with carbon nanotubes, and then assessed the cells for viability, damage to DNA, and the presence of reactive oxygen species.
The researchers found an increase in levels of the reactive oxygen species hydrogen peroxide. Reactive oxygen species cause oxidative stress to cells, and this stress can result in programmed cell death. Dr. Yao and his colleagues discovered that the effect of carbon nanotubes on cells was dosage dependentthe greater the dose, the greater the likelihood of cell death. In contrast, cells exposed to carbon particles that were not nanotubes did not suffer any ill effects, demonstrating that the size of the nanotubes is a factor in their toxicity.
|Contact: Richard Hund|
American Journal of Botany