Carbon nanotube absorption measured in worms, cancer cells

March 28, 2006

University of Michigan researchers have discovered how to measure the absorption of multi-walled carbon nanoparticles into worms and cancer cells, a breakthrough that will revolutionize scientists' understanding of how the particles impact the living environment.

A team led by U-M chemical engineering professor Walter J. Weber Jr. tagged multi-walled carbon nanotubes—one of the most promising nanomaterials developed to date—with the carbon-14 radioactive isotope, which enabled the nanotubes to be tracked and quantified as they were absorbed into living cells. Researchers used cancer cells called HeLa cells, and also measured nanotube uptake in an earthworm and an aquatic type of worm.

The findings were presented Sunday at the 231st American Chemical Society National Meeting in Atlanta. Co-authors of the presentation are graduate student Elijah Petersen and postdoctoral research assistant Qingguo Huang.

Carbon nanotubes were discovered in 1991, and hold great promise in several areas, including pharmacology and for hydrogen storage in fuel cells, Weber said. But despite their promise, a big problem is that it's not known how multi-walled carbon nanotubes will impact the living environment, Weber said.

"While everyone is concerned about this issue, there has been no really adequate way before this development to examine the extent to which they may get into human cells, and what will result if they do," Weber said. "Nobody has been able to do quantitative research on this because no method to measure them has existed until now. We were able to detect them, but had no way to determine how much was there."

In tagging the nanotubes with the isotope, researchers found that about 74 percent of the nanotubes added to a culture of cancer cells were assimilated by the cells after 15 minutes, and 89 percent of nanotubes assimilated after six hours, according to the paper. And the uptake was nearly irreversible, with only about 0.5 percent of the nanotubes releases from the cell after 12 hours.

It's important to understand if and how the multi-walled carbon nanotubes accumulate in living cells, because before the materials can become widely used in society scientists must understand if they'll pass through the food webs and possibly threaten the health of ecosystems and lead to uptake by humans, Petersen said.

"This approach has virtually limitless potential for facilitating important future investigations of the behaviors of carbon nanotubes in environmental and biomedical applications," Petersen said.

Source: University of Michigan

Explore further: Study reveals how nanochannels select potassium ions

Related Stories

Study reveals how nanochannels select potassium ions

August 25, 2015

(Phys.org)—One of the mysteries in biology is how cells can selectively diffuse potassium across a membrane. Biological systems rely on a delicate balance between these potassium and sodium ion concentrations in the surrounding ...

Focused laser power boosts ion acceleration

August 7, 2015

An international team of physicists has used carbon nanotubes to enhance the efficiency of laser-driven particle acceleration. This significant advance brings compact sources of ionizing radiation for medical purposes closer ...

Could stronger, tougher paper replace metal?

July 24, 2015

Researchers at the University of Maryland recently discovered that paper made of cellulose fibers is tougher and stronger the smaller the fibers get. For a long time, engineers have sought a material that is both strong (resistant ...

Manipulating cell membranes using nanotubes

June 1, 2015

Japanese researchers have developed a targeted method for opening up cell membranes in order to deliver drugs to, or manipulate the genes of, individual cells.

Recommended for you

Seeing quantum motion

August 28, 2015

Consider the pendulum of a grandfather clock. If you forget to wind it, you will eventually find the pendulum at rest, unmoving. However, this simple observation is only valid at the level of classical physics—the laws ...

Just how good (or bad) is the fossil record of dinosaurs?

August 28, 2015

Everyone is excited by discoveries of new dinosaurs – or indeed any new fossil species. But a key question for palaeontologists is 'just how good is the fossil record?' Do we know fifty per cent of the species of dinosaurs ...

Smart home heating and cooling

August 28, 2015

Smart temperature-control devices—such as thermostats that learn and adjust to pre-programmed temperatures—are poised to increase comfort and save energy in homes.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.