Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Quantum Dots May be Toxic to Cells, Environment Under Certain Conditions

Abstract:
Researchers in Texas are reporting that quantum dots (QDs) a product of the revolution in nanotechnology increasingly used in electronics, solar cells, and medical imaging devices may be toxic to cells under acidic or alkaline conditions.

Quantum Dots May be Toxic to Cells, Environment Under Certain Conditions

Houston, TX | Posted on January 28th, 2009

Their study, the first to report on how different pH levels may affect the safety of QDs, appears in the Jan.15 issue of ACS' Environmental Science & Technology, a semi-monthly journal.

In the new study, Pedro Alvarez, Shaily Mahendra, and colleagues note that QDs are semiconductor nanocrystals composed of a metal core surrounded by a shell composed of zinc or cadmium sulfide. Scientists are increasingly concerned that these submicroscopic dots, about 1/50,000th the width of a human hair, could decompose during normal use or after disposal. That decomposition could release toxic metals into the environment, posing a health risk to humans and animals.

To explore this concern, the scientists exposed two common types of bacteria that serve as models of cell toxicity and indicators of environmental health to QDs under different conditions of acidity and alkalinity. At near neutral pH levels, bacteria exposed to QDs experienced decreased rates of growth, but did not die. However, at moderately acidic or alkaline conditions, many of the QD-exposed bacteria died as QDs shells decomposed, releasing their content of toxic metals. However, proteins and natural organic matter may be able to mitigate toxicity by complexing metal ions or coating particles. The study cautions, "the release of toxic inorganic constituents during their weathering under acidic or alkaline conditions in the human body or the environment may cause unintended harm that might be difficult to predict with short-term toxicity tests."

ARTICLE #4 FOR IMMEDIATE RELEASE
"Quantum Dot Weathering Results in Microbial Toxicity"

####

For more information, please click here

Contacts:
Pedro J. Alvarez, Ph.D.
Rice University
Houston, Texas 77005
Phone: 713-348-5903
Fax: 713-348-5203
Email:

Copyright © Newswise

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Sandia use confined nanoparticles to improve hydrogen storage materials performance: Big changes from a small package for hydrogen storage February 25th, 2017

New nano approach could cut dose of leading HIV treatment in half February 24th, 2017

Atom-scale oxidation mechanism of nanoparticles helps develop anti-corrosion materials February 24th, 2017

Atomic force imaging used to study nematodes: KFU bionanotechnology lab (head - Dr. Rawil Fakhrullin) has obtained 3-D images of nematodes' cuticles February 23rd, 2017

Discoveries

Sandia use confined nanoparticles to improve hydrogen storage materials performance: Big changes from a small package for hydrogen storage February 25th, 2017

New nano approach could cut dose of leading HIV treatment in half February 24th, 2017

Atom-scale oxidation mechanism of nanoparticles helps develop anti-corrosion materials February 24th, 2017

Atomic force imaging used to study nematodes: KFU bionanotechnology lab (head - Dr. Rawil Fakhrullin) has obtained 3-D images of nematodes' cuticles February 23rd, 2017

Announcements

Sandia use confined nanoparticles to improve hydrogen storage materials performance: Big changes from a small package for hydrogen storage February 25th, 2017

New nano approach could cut dose of leading HIV treatment in half February 24th, 2017

Atom-scale oxidation mechanism of nanoparticles helps develop anti-corrosion materials February 24th, 2017

Atomic force imaging used to study nematodes: KFU bionanotechnology lab (head - Dr. Rawil Fakhrullin) has obtained 3-D images of nematodes' cuticles February 23rd, 2017

Environment

Meta-lenses bring benchtop performance to small, hand-held spectrometer: Game-changing nanostructure-based lenses allow smaller devices, increased functionality February 9th, 2017

NIST updates 'sweet' 1950s separation method to clean nanoparticles from organisms January 27th, 2017

Investigating the impact of natural and manmade nanomaterials on living things: Center for Environmental Implications of Nanotechnology develops tools to assess current and future risk January 9th, 2017

PCATDES Starts Field Testing of Photocatalytic Reactors in South East Asia December 28th, 2016

Safety-Nanoparticles/Risk management

NIST updates 'sweet' 1950s separation method to clean nanoparticles from organisms January 27th, 2017

Nanoparticle exposure can awaken dormant viruses in the lungs January 17th, 2017

Investigating the impact of natural and manmade nanomaterials on living things: Center for Environmental Implications of Nanotechnology develops tools to assess current and future risk January 9th, 2017

First time physicists observed and quantified tiny nanoparticle crossing lipid membrane November 7th, 2016

Quantum Dots/Rods

Particle Works creates range of high performance quantum dots February 23rd, 2017

Strem Chemicals and Dotz Nano Ltd. Sign Distribution Agreement for Graphene Quantum Dots Collaboration February 21st, 2017

Carbon dots dash toward 'green' recycling role: Rice scientists, colleagues use doped graphene quantum dots to reduce carbon dioxide to fuel December 18th, 2016

Two electrons go on a quantum walk and end up in a qudit: Russian scientists find a way to reliably connect quantum elements December 13th, 2016

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project