Home > Press > Tracking down the effect of nanoparticles
|Cell cultures of lung epithelial cells (in the right-hand box) were exposed to an aerosol of cerium oxide nanoparticles in a special glove box. During the exposure of the cell cultures, the nanoparticles were freshly produced by flame synthesis in the left half of the box. |
Cerium oxide is a ceramic nano-abrasive. Scientists have now examined, under conditions close to reality, what happens when it is breathed in and deposited on the lung surface. Initially, the result was rather reassuring.
Tracking down the effect of nanoparticles
Zurich, Switzerland | Posted on April 12th, 2009
Synthetic nanoparticles are ubiquitous nowadays: either as an additive to building materials, whose properties they improve; in cosmetics, mainly in sun creams and toothpaste; or in foodstuffs, to thicken them or brighten their color. However, nano-safety research, i.e. knowledge of how nanoparticles interact with their environment and specifically with a living organism, is still largely in its infancy.
However, this is one of the central topics for the research group led by Wendelin Stark, Assistant Professor at the Institute for Chemical and Bio-engineering of ETH Zurich. The group carries out tests over and over again to investigate the effect nanoparticles have on their surroundings (see the ETH Life article of 15.07.2008)
Conditions close to reality
Together with the research group led by Peter Gehr, Professor of Histology at the University of Bern, the scientists have now used a completely new method and a new type of lung cell culture to examine how cerium oxide nanoparticles act on the cells. The aim was to study the toxicity of cerium oxide, which is used in large amounts as an abrasive, mainly in the manufacture of semiconductor chips. Although, as a rule, this takes place in a hermetically sealed room from which people are excluded, the researchers now simulated a situation in which ceramic nanomaterial is inhaled directly, for example if nanoparticles are manufactured without protection or the powder is handled incorrectly.
The researchers did this by using what is called flame spray synthesis to spray cerium oxide nanoparticles in a closed glove box, thus simulating aerosols. A fan distributed the aerosols uniformly in the box, about 2.5 cubic meters in size, in which the aerosols were sprayed on to the cultured lung cells for ten, twenty and thirty minutes. The ETH researches hit upon the idea when they spoke to Barbara Rothen-Rutishauser, a scientist from Bern and first author of the paper. She told them about the new type of cell culture. The results of the interdisciplinary collaboration were published on-line in "Environmental Science and Technology".
The innovative aspect of the method is the special cell culture combined with the use of flame spray synthesis. The cell culture of lung epithelial cells grows on a permeable membrane. The lower surface of the epithelial cells is immersed in a medium and their upper surface is covered with a natural liquid layer. Thus the cell culture is very similar to the surface of the lung. As a result of the aerosol production, the spray process is also close to reality. The combination of these two techniques showed how inhaled nanoparticles are deposited on the lung surface. In conventional methods for such experiments up to now, cell cultures were bathed in nanoparticle solutions. However, this can cause the nanoparticles to agglomerate, which alters their properties; moreover, the lung surface is wet in a different way. Consequently, the behavior of the cells might also change.
No cell death
The scientists chose cerium oxide for their study, mainly because the material does not occur physiologically in cells, meaning that only the effect of the nanoparticle on the cell is observed. The longer the cultures were sprayed for, the more nanoparticles were deposited on the lung cells. The scientists observed that the cells were not destroyed, i.e. they did not die. However, the permeability of the cell layer increased. Therefore, the researchers suspect that certain structures of particular proteins that seal the interstices between the epithelial cells had altered under the influence of the nanoparticles. The production of a substance in the cell which is associated with oxidative stress and which could result in DNA damage could also be observed.
Long-term effects unknown
Robert Grass, group leader in Wendelin Stark's group, explains: "However, we were unable to observe the effect of the particles on the cells over a prolonged time." This is because the cultures must be subjected to further processing to allow them to be examined under a microscope. In a next step, the researchers plan to replicate even more realistic conditions by using what are known as triple cell co-cultures that simulate human cellular respiratory tract barriers. For example, they want to find out how the body's phagocytes and "waste disposal agents", known as macrophages, deal with nanoparticles.
Author: Simone Ulmer
Rothen-Rutishauser B, Grass RN, Blank F, Limbach LK, Mühlfeld C, Brandenberger C, Raemy DO, Gehr P & Stark WJ: Direct Combination of Nanoparticle Fabrication and Exposure to Lung Cell Cultures in a Closed Setup as a Method To Simulate Accidental Nanoparticle Exposure of Humans, Environ. Sci. Technol., On-line publication 2 March 2009 DOI: 10.1021/es8029347
About ETH Zurich
ETH Zurich is an institution of the Swiss Confederation dedicated to higher learning and research. Together with the ETH Lausanne and four research institutes, it forms the federally directed, and to a major degree financed, ETH domain. The institutions of the ETH domain uphold their autonomy and identity on the basis of the ETH Federal Law and in the full awareness of their social, economic and cultural responsibility to the nation and its citizens.
For more information, please click here
HG F 41
Fax +41 44 632 17 16
Copyright © ETH Zurich
If you have a comment, please Contact
Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
News and information
Maximum Precision in 3D Printing: New complete solution makes additive manufacturing standard for microfabrication February 26th, 2015
Real-time observation of bond formation by using femtosecond X-ray liquidography February 26th, 2015
Bruker-Sponsored Sixth AFM BioMed Conference Highlights Increasing Impact of AFM in Biological Applications February 26th, 2015
Graphene shows potential as novel anti-cancer therapeutic strategy: University of Manchester scientists have used graphene to target and neutralise cancer stem cells while not harming other cells February 26th, 2015
Fonon Announces 3D Metal Sintering Technology: Emerging Additive Nano Powder Manufacturing Technology August 28th, 2014
INSCX™ exchange launches upgraded Physical Trade Platform December 7th, 2012
Iran's Nanotechnology Capabilities Displayed in Russia Open Innovations Expo 2012 November 10th, 2012
Application of Adamantane November 7th, 2012
Preparing for Nano
Durnham University's DEEPEN project comes to a close September 26th, 2012
Technical Seminar at ANFoS 2012 August 22nd, 2012
Nanotechnology shows we can innovate without economic growth April 12th, 2012
Thailand to host NanoThailand 2012 December 18th, 2011
Simple, Cost-Efficient Method Used to Determine Toxicants Growing in Pistachio February 26th, 2015
Iranian Scientists Find Solution to Measure Species Existing in Liquids February 6th, 2015
Best practice guide for the safe handling and use of nanoparticles in packaging industries now available: A novel best practice guide is now available to support the safe handling and use of nanoparticles in packaging industries February 2nd, 2015
Everything You Need To Know About Nanopesticides January 30th, 2015
In quest for better lithium-air batteries, chemists boost carbon's stability: Nanoparticle coatings improve stability, cyclability of '3DOm' carbon February 25th, 2015
Purification of Industrial Wastewater Using Visible-Light Sensitive Photocatalysts February 24th, 2015
Increasing Efficiency of Cooling Devices in Oil, Gas Industries February 21st, 2015
Ligar secures investment from Wallace Corporation to commercialise polymers that pick out good and bad molecules: Ground-breaking science innovation removes molecules in the wrong place from liquids February 15th, 2015
Sunblock poses potential hazard to sea life August 20th, 2014
AQUANOVA receives Technology Leadership Award 2014 FROST & SULLIVAN honors NovaSOL® Technology again August 12th, 2014
Nanotechnology used in sunscreens: a Mexican achievement May 14th, 2014
Production of Nanocapsule from Sea-Buckthorn Extract in Iran May 3rd, 2014
Potential toxicity of cellulose nanocrystals examined in Industrial Biotechnology journal February 19th, 2015
A breakthrough in nanotoxicology by INRS researchers: Silver nanoparticles and inflammation February 18th, 2015
“Nanorama Laboratory“: Free Tool on Safe Handling of Nanomaterials Now Available in English! February 4th, 2015
Worms lead way to test nanoparticle toxicity: Rice University study validates low-cost, high-throughput technology February 2nd, 2015