Featured Research

from universities, journals, and other organizations

Multi-laboratory Study Sizes Up Nanoparticle Sizing

Date:
August 11, 2009
Source:
National Institute of Standards and Technology (NIST)
Summary:
As a result of a major inter-laboratory study, the standards body ASTM International has been able to update its guidelines for a commonly used technique for measuring the size of nanoparticles in solutions.

As a result of a major inter-laboratory study, the standards body ASTM International has been able to update its guidelines for a commonly used technique for measuring the size of nanoparticles in solutions.

Related Articles


The study, which was organized principally by researchers from the National Institute of Standards and Technology (NIST) and the Nanotechnology Characterization Laboratory of the National Cancer Institute, enabled updated guidelines that now include statistically evaluated data on the measurement precisions achieved by a wide variety of laboratories applying the ASTM guide.

Data from the inter-laboratory comparison gathered from 26 different laboratories will provide a valuable benchmark for labs measuring the sizes and size distribution of nanoparticles suspended in fluids—one of the key measurements in nanotechnology research, especially for biological applications, according to materials researcher Vince Hackley, who led the NIST portion of the study.

Size is an important characteristic of nanoparticles in a variety of potential uses, but particularly in biotech applications where they are being studied for possible use in cancer therapies. The size of a nanoparticle can significantly affect how cells respond to it.

One widely used method for rapidly measuring the size profile of nanoparticles in, say, a buffer solution, is photon correlation spectroscopy (PCS), sometimes called "dynamic light scattering." The technique is powerful but tricky. The basic idea is to pass a laser beam through the solution and then to measure how rapidly the scattered light is fluctuating—faster moving particles cause the light scattering to change more rapidly than slower moving particles. If you know that, plus several basic parameters such as the viscosity and temperature of the fluid, says Hackley, and you can control a number of potential sources of error, then you can calculate meaningful size values for the particles.

ASTM standard E2490 is a guide for doing just that. The goal of the ASTM-sponsored study was to evaluate just how well a typical lab could expect to measure particle size following the guide. "The study really assesses, in a sense, how well people can apply these techniques given a fairly well-defined protocol and a well-defined material," explains Hackley. Having a "well-defined material" was a key factor, and one thing that made the experiment possible was the release this past year of NIST's first nanoparticle reference standards for the biomedical research community—NIST-certified solutions of gold nanoparticles of three different diameters, a project also supported by NCL.

The inter-laboratory study required participating labs to measure particle size distribution in five samples—the three NIST reference materials and two solutions of dendrimers, a class of organic molecules that can be synthesized within a very narrow size range. The labs used not only PCS, but also electron and atomic force microscopy. The results were factored into precision and bias tables that are now a part of the ASTM standard.

For more on the study and ASTM standard E2490, see the ASTM International release "Extensive Interlaboratory Study Incorporated into Revision of ASTM Nanotechnology Standard" at http://astmnewsroom.org/default.aspx?pageid=1840.


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology (NIST). Note: Materials may be edited for content and length.


Cite This Page:

National Institute of Standards and Technology (NIST). "Multi-laboratory Study Sizes Up Nanoparticle Sizing." ScienceDaily. ScienceDaily, 11 August 2009. <www.sciencedaily.com/releases/2009/08/090811191658.htm>.
National Institute of Standards and Technology (NIST). (2009, August 11). Multi-laboratory Study Sizes Up Nanoparticle Sizing. ScienceDaily. Retrieved December 27, 2014 from www.sciencedaily.com/releases/2009/08/090811191658.htm
National Institute of Standards and Technology (NIST). "Multi-laboratory Study Sizes Up Nanoparticle Sizing." ScienceDaily. www.sciencedaily.com/releases/2009/08/090811191658.htm (accessed December 27, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Saturday, December 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Christmas Gifted Drones Are Already Causing Problems

Christmas Gifted Drones Are Already Causing Problems

Newsy (Dec. 25, 2014) — Commercial drones were a popular gift this Christmas, but flying one is harder than it looks, and the results can range from comical to catastrophic. Video provided by Newsy
Powered by NewsLook.com
NASA Cameras Capture Solar Flare

NASA Cameras Capture Solar Flare

Reuters - US Online Video (Dec. 25, 2014) — NASA cameras capture images of intense solar flare on the sun. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Ukrainian Coal Miners Work to Stave Off Electricity Shortage

Ukrainian Coal Miners Work to Stave Off Electricity Shortage

AFP (Dec. 24, 2014) — Coal miners in the separatist east of Ukraine work to ensure there won't be electricity shortages during the coldest months of winter, but the country has declared a state of emergency in its electricity market. Duration: 00:59 Video provided by AFP
Powered by NewsLook.com
Tech's Next Step: Social Change

Tech's Next Step: Social Change

Reuters - Business Video Online (Dec. 23, 2014) — Technology is constantly changing lives but 100 firms have done more than most. As Joel Flyn reports a malaria diagnosis app, do-it-yourself architecture and camera glasses have recently won awards for driving social change. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins