Featured Research

from universities, journals, and other organizations

Some, Like Russian Dolls, Fit Inside Each Other: Self-Assembled Nanospheres May Be Helpful Against Disease Or Terrorism, Or As Fillers And Coatings

Date:
March 19, 1999
Source:
Sandia National Laboratories
Summary:
Self-assembling nanospheres that fit inside each other like Russian dolls are one form of a broad range of nanospheres created in the past 12 months at the Department of Energy's (DOE) Sandia National Laboratories. The achievement, which has medical, industrial and military potential, is featured in the journal Nature.

ALBUQUERQUE, N.M. -- Self-assembling nanospheres that fit inside each other like Russian dolls are one form of a broad range of nanospheres created in the past 12 months at the Department of Energy's (DOE) Sandia National Laboratories. The achievement, which has medical, industrial and military potential, is featured in the March 18 issue of the journal Nature.

According to one reviewer, the spheres demonstrate an unprecedented control over organic and inorganic nanoscale self-assemblies, and represent a major step forward in control of these techniques.

The durable silica spheres, which range in size from 2 to 50 nanometers, form in a few seconds, are small enough to be introduced into the body, and have uniform pores that enable controlled release of drugs. The spheres can absorb organic and inorganic substances including small particles of iron, which means they can be controlled by magnets and the contents released as needed.

The small porous particles also have characteristics superior to fillers used in encapsulants for weapons and tools. The expansion coefficients of polymers and the metallic devices they cradle usually differ substantially. This means that temperature variations cause the encapsulants to stress the devices they are meant to protect. The induced stresses can decrease longevity of a device. Nanosphere fillers would occupy the same volume, but because they are porous can expand and contract with much less stress.

Lastly, the Sandia nanospheres may be useful as coatings on silicon chips whose increasingly tiny circuits require a medium that has a lower dielectric constant and stores less heat.

Some pore shapes trap materials, while others allow free flow in and out of the spheres.

The different kinds of sphere porosity may resemble slits between onion-like layers of silica, or a honeycomb's hexagonal patterns of holes, or the cubic gaps in a network of connected tinkertoys.

"The ability to control these different porosities make them useful for all kinds of applications," says Sandia lead investigator Jeff Brinker. "If they were simply porous particles, they would not be nearly so interesting."

The mixture begins with a homogeneous solution of soluble silica plus surfactant prepared in an ethanol water solvent. In a continuous process that takes about six seconds per particle, the aerosol particles are dried, heated and collected.

"We start out with liquid droplets that we pass through a reactor," says Brinker. "As liquid starts to evaporate, the rest of the material self-assembles into a completely ordered particle that, when heated, maintains its shape." The spheres are the most intriguing in a series of advances by Brinker and his research associates, all reported in previous publications of Nature.

Prior results by Brinker's team used simpler but similar techniques to self-assemble highly porous thin films to overlay and greatly increase the porosity and therefore sensitivity of handheld detectors.

Following that achievement came self-assembled laminates that resemble seashells in appearance and properties. This method of self-assembly improved the strength of human-created materials by sandwiching yielding layers of polymers between hard inorganic layers, increasing toughness and preventing the spreading of cracks.

The nanospheres -- essentially a three-dimensional creation rather than a film or layering of films -- were created by drying liquid droplets blowing through a furnace, rather than evaporation of a liquid layer deposited on a substrate.

The work was supported by DOE's Basic Energy Science Program, and by the University of New Mexico (UNM)/National Science Foundation Center for Micro-Engineered Materials.

Other authors -- all at UNM's Advanced Materials Laboratory -- are Yunfeng Lu, Hongyou Fan, Aaron Stump, Tim Ward, and Thomas Rieker.

###

Sandia is a multiprogram DOE laboratory, operated by a subsidiary of Lockheed Martin Corp. With main facilities in Albuquerque, N.M., and Livermore, Calif., Sandia has major research and development responsibilities in national security, energy, and environmental technologies.


Story Source:

The above story is based on materials provided by Sandia National Laboratories. Note: Materials may be edited for content and length.


Cite This Page:

Sandia National Laboratories. "Some, Like Russian Dolls, Fit Inside Each Other: Self-Assembled Nanospheres May Be Helpful Against Disease Or Terrorism, Or As Fillers And Coatings." ScienceDaily. ScienceDaily, 19 March 1999. <www.sciencedaily.com/releases/1999/03/990319061848.htm>.
Sandia National Laboratories. (1999, March 19). Some, Like Russian Dolls, Fit Inside Each Other: Self-Assembled Nanospheres May Be Helpful Against Disease Or Terrorism, Or As Fillers And Coatings. ScienceDaily. Retrieved August 1, 2014 from www.sciencedaily.com/releases/1999/03/990319061848.htm
Sandia National Laboratories. "Some, Like Russian Dolls, Fit Inside Each Other: Self-Assembled Nanospheres May Be Helpful Against Disease Or Terrorism, Or As Fillers And Coatings." ScienceDaily. www.sciencedaily.com/releases/1999/03/990319061848.htm (accessed August 1, 2014).

Share This




More Matter & Energy News

Friday, August 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Tesla, Panasonic Ink Deal To Make Huge Battery 'Gigafactory'

Tesla, Panasonic Ink Deal To Make Huge Battery 'Gigafactory'

Newsy (July 31, 2014) The deal will help build a massive battery factory that Tesla says will produce 500,000 lithium batteries by 2020. Video provided by Newsy
Powered by NewsLook.com
Britain Testing Driverless Cars on Roadways

Britain Testing Driverless Cars on Roadways

AP (July 30, 2014) British officials said on Wednesday that driverless cars will be tested on roads in as many as three cities in a trial program set to begin in January. Officials said the tests will last up to three years. (July 30) Video provided by AP
Powered by NewsLook.com
7 Ways to Use Toothpaste: Howdini Hacks

7 Ways to Use Toothpaste: Howdini Hacks

Howdini (July 30, 2014) Fresh breath and clean teeth are great, but have you ever thought, "my toothpaste could be doing more". Well, it can! Lots of things! Howdini has 7 new uses for this household staple. Video provided by Howdini
Powered by NewsLook.com
Smoked: 2015 Ducati Diavel Vs 2014 Chevy Corvette Stingray Drag Race

Smoked: 2015 Ducati Diavel Vs 2014 Chevy Corvette Stingray Drag Race

Cycle World (July 30, 2014) The Bonnier Motorcycle Group presents Smoked; a three part video series. In this episode the 2015 Ducati Diavel takes on the 2014 Chevy Corvette Stingray Video provided by Cycle World
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:
from the past week

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