Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



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

Beyond wires: Bubble technology powers next-generation electronics:New laser-based bubble printing technique creates ultra-flexible liquid metal circuits November 8th, 2024

Nanoparticle bursts over the Amazon rainforest: Rainfall induces bursts of natural nanoparticles that can form clouds and further precipitation over the Amazon rainforest November 8th, 2024

Nanotechnology: Flexible biosensors with modular design November 8th, 2024

Exosomes: A potential biomarker and therapeutic target in diabetic cardiomyopathy November 8th, 2024

Discoveries

Breaking carbon–hydrogen bonds to make complex molecules November 8th, 2024

Exosomes: A potential biomarker and therapeutic target in diabetic cardiomyopathy November 8th, 2024

Turning up the signal November 8th, 2024

Nanofibrous metal oxide semiconductor for sensory face November 8th, 2024

Announcements

Nanotechnology: Flexible biosensors with modular design November 8th, 2024

Exosomes: A potential biomarker and therapeutic target in diabetic cardiomyopathy November 8th, 2024

Turning up the signal November 8th, 2024

Nanofibrous metal oxide semiconductor for sensory face November 8th, 2024

Environment

Nanoparticle bursts over the Amazon rainforest: Rainfall induces bursts of natural nanoparticles that can form clouds and further precipitation over the Amazon rainforest November 8th, 2024

New method in the fight against forever chemicals September 13th, 2024

Catalyzing environmental cleanup: A highly active and selective molecular catalyst and electrified membrane: Innovative electrochemical catalyst breaks down trichloroethylene pollutants at unprecedented rate September 13th, 2024

$900,000 awarded to optimize graphene energy harvesting devices: The WoodNext Foundation's commitment to U of A physicist Paul Thibado will be used to develop sensor systems compatible with six different power sources January 12th, 2024

Safety-Nanoparticles/Risk management

First human trial shows ‘wonder’ material can be developed safely: A revolutionary nanomaterial with huge potential to tackle multiple global challenges could be developed further without acute risk to human health, research suggests February 16th, 2024

New research may make future design of nanotechnology safer with fewer side effects: Study shows a promising strategy to reduce adverse reactions to nanoparticles by using complement inhibitors October 6th, 2023

Tests find no free-standing nanotubes released from tire tread wear September 8th, 2023

Billions of nanoplastics released when microwaving baby food containers: Exposure to plastic particles kills up to 75% of cultured kidney cells July 21st, 2023

Quantum Dots/Rods

A new kind of magnetism November 17th, 2023

IOP Publishing celebrates World Quantum Day with the announcement of a special quantum collection and the winners of two prestigious quantum awards April 14th, 2023

Qubits on strong stimulants: Researchers find ways to improve the storage time of quantum information in a spin rich material January 27th, 2023

NIST’s grid of quantum islands could reveal secrets for powerful technologies November 18th, 2022

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project