Carbon nanotubes resemble asbestos fibers in their form. Unfortunately, long, pure nanotubes also seem to have asbestos-like pathogenicity.
In the journal Angewandte Chemie, a European research team has now reported that chemical modifications, for example with tri(ethylene glycol), can alleviate this problem if the modification makes their surface more water-friendly and reduces the effective length of the tubes.
Due to their unique physical, chemical, and electronic properties, carbon nanotubes have become one of the most popular nanomaterials. They are used in electronics, for reinforcing plastics, and in biomedicine as nanotransporters to carry drugs into cells. For many of these applications, particularly in the area of biology, it is necessary to chemically alter the tubes by attaching molecules to their surfaces.
However, the industrial production of carbon nanotubes could bring health risks with it. Studies have shown that multi-walled nanotubes that are more than 20 µm long act like asbestos fibers, causing inflammation followed by granulomas—inflammation-induced knotlike tissue growths. This occurs because the macrophages of our immune system cannot absorb and remove the long fibers. Shorter nanotubes and those with certain surface modifications have now been shown to alleviate toxicity.
A team led by Maurizio Prato, Alberto Bianco, and Kostas Kostarelos wanted to determine what role the chemical modifications have in resolving the toxic risk from the tubes. The scientists from University College London (UK), the CNRS in Strasbourg (France), and the University of Trieste (Italy) attached either hydrocarbon chains or tri(ethylene glycol) chains as side-groups on multi-walled carbon nanotubes and compared their effects to those of unmodified tubes. The results show that the unmodified nanotubes and those with hydrocarbon chains lead to asbestos-like inflammation and granulomas in mice.However, the carbon nanotubes with tri(ethylene glycol) chains do not.
The researchers believe that the modification with the tri(ethylene glycol) chain breaks apart the tubes from each other so that they interact in the body as shorter, much more hydrophilic individual fibers, whereas both the unmodified tubes and those with apolar hydrocarbons on their surfaces interact with tissue as longer bundles of individual nanotubes.
The researchers conclude that only those modifications that lead to a disentangling of the bundles can alleviate the toxicological problems.About the Author
Author: Alberto Bianco, CNRS, Institut de Biologie Moléculaire et Cellulaire, Strasbourg (France), mailto:email@example.com
Title: Asbestos-like Pathogenicity of Long Carbon Nanotubes Can be Alleviated by Chemical Functionalization
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201207664
Alberto Bianco | Angewandte Chemie
Designer cells: artificial enzyme can activate a gene switch
22.05.2018 | Universität Basel
Flow of cerebrospinal fluid regulates neural stem cell division
22.05.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
22.05.2018 | Earth Sciences
22.05.2018 | Trade Fair News
22.05.2018 | Trade Fair News