Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button


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

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.


Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press


Nanotech-based sensor developed to measure microRNAs in blood, speed cancer detection November 19th, 2015

A simple, rapid test to help ensure safer meat November 19th, 2015

Plasma Focus Device Applied to Produce Zinc Oxide Nanofilms November 18th, 2015

Researchers design and patent graphene biosensors: The Moscow Institute of Physics and Technology is patenting biosensor chips based on graphene, graphene oxide and carbon nanotubes that will improve the analysis of biochemical reactions and accelerate the development of novel dr November 16th, 2015

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

New 'self-healing' gel makes electronics more flexible November 25th, 2015

Scientists design a QKD-based quantum private query with no failure November 25th, 2015

MIT mathematicians identify limits to heat flow at the nanoscale: New formula identifies limits to nanoscale heat transfer, may help optimize devices that convert heat to electricity November 25th, 2015

Physicists explain the unusual behavior of strongly disordered superconductors: Using a theory they developed previously, the scientists have linked superconducting carrier density with the quantum properties of a substance November 25th, 2015


Electric fields remove nanoparticles from blood with ease November 24th, 2015

Using light-force to study single molecules November 23rd, 2015

Breakthrough allows tracking of single molecules in 3-D with nanoscale accuracy:New method builds on Nobel Prize-winning technique, with exciting implications for understanding the inner workings of cells and neurons November 23rd, 2015

New EU project designed to link diagnosis and treatment of diseases over the long term: Joint research project aims at the improvement of companion diagnostics and therapy of tumor diseases November 23rd, 2015

The latest news from around the world, FREE

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

Nanotechnology Now Featured Books


The Hunger Project

Car Brands
Buy website traffic