Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > How to count nanoparticles

Abstract:
Nanoparticles of a substance can be counted and the size distribution can be determined by dispersing the nanoparticles into a gas. But some nanoparticles tend to aggregate when the surrounding conditions change. Scientists at the University of Gothenburg, Sweden, have shown that it is possible to sort and count the particles, even when they have formed aggregates.

How to count nanoparticles

Gothenburg, Sweden | Posted on October 11th, 2011

"Nanoparticles are already used in many everyday products, such as sunscreen and cosmetics. It is important to be able to determine their size, shape and surface area, in order to be able to improve their properties within various areas of application", says Ann-Cathrin Johnsson of the Department of Chemistry at the University of Gothenburg.

A nanoparticle is a particle with a diameter that is much smaller than one millionth of a metre. Such small particles are not influenced by gravity and thus they do not fall to the bottom of a liquid or gas, and instead spread out throughout the container. Their area of contact with the surrounding medium is very large due to their small size, as a result many interesting properties arise. Nanoparticles of a substance behave, quite simply, differently than large particles of the same substance.

Certain types of nanoparticles can start to aggregate in special conditions, and sometimes a so called gel may form. The process is similar to that of boiling an egg: the proteins in the egg white aggregate and form the solid-like structure that we recognise as boiled egg.

Ann-Cathrin Johnsson's thesis work has studied one of these aggregating systems, colloidal silica. The gel that forms when salt is added to colloidal silica can be used, for example, to seal rock and to stabilise soil.

"I started with a method that had been used only for analysing nanoparticles that had not aggregated, and developed it further. Nanoparticles that have aggregated can be analysed individually if a colloidal silica gel, which contains these aggregated nanoparticles, is first diluted and then dispersed into the gas phase. If the samples are analysed immediately after being diluted, this method gives an accurate picture of the gelated system.

####

For more information, please click here

Contacts:
Ann-Cathrin Johnsson
University of Gothenburg
+46 31 786 90 67

Copyright © AlphaGalileo

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

GS7 Graphene Sensor maybe Solution in Fight Against Cancer January 25th, 2015

Toyocolor to Launch New Carbon Nanotube Materials at nano tech 2015 January 24th, 2015

NANOPOSTER 2015 - 5th Virtual Nanotechnology Conference - call for abstracts January 24th, 2015

Nanosensor Used for Simultaneous Determination of Effective Tea Components January 24th, 2015

Discoveries

GS7 Graphene Sensor maybe Solution in Fight Against Cancer January 25th, 2015

Nanosensor Used for Simultaneous Determination of Effective Tea Components January 24th, 2015

The latest fashion: Graphene edges can be tailor-made: Rice University theory shows it should be possible to tune material's properties January 24th, 2015

Silver nanowires demonstrate unexpected self-healing mechanism: The material has potential for flexible electronics January 23rd, 2015

Announcements

GS7 Graphene Sensor maybe Solution in Fight Against Cancer January 25th, 2015

Toyocolor to Launch New Carbon Nanotube Materials at nano tech 2015 January 24th, 2015

NANOPOSTER 2015 - 5th Virtual Nanotechnology Conference - call for abstracts January 24th, 2015

Nanosensor Used for Simultaneous Determination of Effective Tea Components January 24th, 2015

Tools

Graphene brings quantum effects to electronic circuits January 22nd, 2015

EnvisioNano: An image contest hosted by the National Nanotechnology Initiative (NNI) January 22nd, 2015

New Molecular Beam Epitaxy deposition equipment at the ICN2 January 22nd, 2015

New method to generate arbitrary optical pulses January 21st, 2015

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 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE