Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > News > The challenge of creating visible and nontoxic nanomaterials for sensing

November 2nd, 2007

The challenge of creating visible and nontoxic nanomaterials for sensing

Abstract:
Nanotechnologies opened a new door towards the development of novel techniques and devices for probing biological systems such as biomolecules and single cells. The most reliable bioprobes today rely on fluorescent or radioactive labeling. Phosphorescent emitters are preferable for use in sensing or biological labeling schemes because the emission occurs over a very long timescale (for nanoscientists, 'very long timescale' is a relative term; here we are talking about 1 microsecond). Especially semiconductor nanocrystals (quantum dots) possess several properties that make them very attractive for fluorescent tagging: broad excitation spectrum, narrow emission spectrum, precise tunability of their emission peak, longer fluorescence lifetime than organic fluorophores and negligible photobleaching. Scientists have discovered that these nanocrystals can enable researchers to study cell processes at the level of a single molecule and may significantly improve the diagnosis and treatment of diseases such as cancers. However, the band gap of most emissive semiconductors, with the exception of cadmium-containing materials, is either too high or too low to easily make visible emitting quantum dots. Unfortunately, cadmium is quite toxic and therefore not really suitable for medical applications. In a step towards circumventing the issues with cadmium toxicity, researchers have make progress in demonstrating visible phosphorescence from doped nanocrystal systems. A recent example is the synthesis of a nanoscopic material composed of the non-toxic elements zinc, selenium, sulfur and manganese which displays efficient visible emission.

Source:
nanowerk.com

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Sensors

Compact Vibration Harvester Power Supply with Highest Efficiency Opens Door to “Fix-and-Forget” Sensor Nodes July 23rd, 2014

Nano-sized Chip "Sniffs Out" Explosives Far Better than Trained Dogs: TAU researcher's groundbreaking sensor detects miniscule concentrations of hazardous materials in the air July 23rd, 2014

Tiny laser sensor heightens bomb detection sensitivity July 19th, 2014

Iranian Scientists Use Nanosensors to Achieve Best Limit for Early Cancer Diagnosis July 19th, 2014

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals

Iranian Scientists Produce Transparent Nanocomposite Coatings with Longer Lifetime July 24th, 2014

A Crystal Wedding in the Nanocosmos July 23rd, 2014

Nano-sized Chip "Sniffs Out" Explosives Far Better than Trained Dogs: TAU researcher's groundbreaking sensor detects miniscule concentrations of hazardous materials in the air July 23rd, 2014

Penn Study: Understanding Graphene’s Electrical Properties on an Atomic Level July 22nd, 2014

Nanobiotechnology

Production of Non-Virus Nanocarriers with Highest Amount of Gene Delivery July 17th, 2014

Physicists Use Computer Models to Reveal Quantum Effects in Biological Oxygen Transport: The team solved a long-standing question by explaining why oxygen – and not deadly carbon monoxide – preferably binds to the proteins that transport it around the body. July 17th, 2014

Tiny DNA pyramids enter bacteria easily -- and deliver a deadly payload July 9th, 2014

Artificial cilia: Scientists from Kiel University develop nano-structured transportation system July 4th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE