Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Nanoparticles assemble by millions to encase oil drops

Abstract:
Designer 'nanobatons' could be used to trap oil, deliver drugs

Nanoparticles assemble by millions to encase oil drops

Houston, TX | Posted on May 29th, 2008

In a development that could lead to new technologies for cleaning up oil spills and polluted groundwater, scientists at Rice University have shown how tiny, stick-shaped particles of metal and carbon can trap oil droplets in water by spontaneously assembling into bag-like sacs.

The tiny particles were found to assemble spontaneously by the tens of millions into spherical sacs as large as BB pellets around droplets of oil in water. In addition, the scientists found that ultraviolet light and magnetic fields could be used to flip the nanoparticles, causing the bags to instantly turn inside out and release their cargo -- a feature that could ultimately be handy for delivering drugs.

"The core of the nanotechnology revolution lies in designing inorganic nanoparticles that can self-assemble into larger structures like a 'smart dust' that performs different functions in the world - for example, cleaning up pollution," said lead research Pulickel Ajayan, Rice's Benjamin M. and Mary Greenwood Anderson Professor in Mechanical Engineering and Materials Science. "Our approach brings the concept of self-assembling, functional nanomaterials one step closer to reality."

The research was published online today by the American Chemical Society's journal Nano Letters.

The multisegmented nanowires, akin to "nanoscale batons," were made by connecting two nanomaterials with different properties, much like an eraser is attached to the end of a wooden pencil. In the study, the researchers started with carbon nanotubes -- hollow tubes of pure carbon. Atop the nanotubes, they added short segments of gold. Ajayan said that by adding various other segments -- like sections of nickel or other materials -- the researchers can create truly multifunctional nanostructures.

The tendency of these nanobatons to assemble in water-oil mixtures derives from basic chemistry. The gold end of the wire is water-loving, or hydrophilic, while the carbon end is water-averse, or hydrophobic. The thin, water-tight sacs that surround all living cells are formed by interlocking arrangements of hydrophilic and hydrophobic chemicals, and the sac-like structures created in the study are very similar.

Ajayan, graduate student Fung Suong Ou and postdoctoral researcher Shaijumon Manikoth demonstrated that oil droplets suspended in water became encapsulated because of the structures' tendency to align their carbon ends facing the oil. By reversing the conditions -- suspending water droplets in oil - the team was able to coax the gold ends to face inward and encase the water.

"For oil droplets suspended in water, the spheres give off a light yellow color because of the exposed gold ends," Ou said. "With water droplets, we observe a dark sphere due to the protruding black nanotubes."

The team is next preparing to test whether chemical modifications to the "nanobatons" could result in spheres that can both capture and break down oily chemicals. For example, they hope to attach catalysts to the water-hating ends of the nanowires that will cause compounds like trichloroethene, or TCE, to break into nontoxic constituents. Another option would be to attach drugs whose release can be controlled with an external stimulus.

"The idea is to go beyond just capturing the compound and initiate a process that will make it less toxic," Ajayan said. "We want to build upon the method of self assembly and start adding functionality so these particles can carry out tasks in the real world."

The research was supported by Rice University, Applied Materials Inc. and the New York State Foundation for Science, Technology and Innovation.

####

About Rice University
Located in Houston, Rice University is consistently ranked one of America's best teaching and research universities. Known for its "unconventional wisdom," Rice is distinguished by its: size -- 3,001 undergraduates and 2,144 graduate students; selectivity --12 applicants for each place in the freshman class; resources -- an undergraduate student-to-faculty ratio of 5-to-1; sixth largest endowment per student among American private research universities; residential college system, which builds communities that are both close-knit and diverse; and collaborative culture, which crosses disciplines, integrates teaching and research, and intermingles undergraduate and graduate work.

For more information, please click here

Contacts:
Jade Boyd

713-348-6778

Copyright © Rice University

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

Feynman Prize Winners Announced! April 26th, 2015

New ASTM Standards Will Help Educate Present and Future Nanotechnology Workforces April 26th, 2015

Heat makes electrons’ spin in magnetic superconductors April 26th, 2015

QD Vision Wins 2015 Bronze Edison Award for Color IQ™ Quantum Dot Technology April 26th, 2015

Nanomedicine

Northwestern scientists develop first liquid nanolaser: Technology could lead to new way of doing 'lab on a chip' medical diagnostics April 25th, 2015

Nanotech-enabled moisturizer speeds healing of diabetic skin wounds: Spherical nucleic acids silence gene that interferes with wound healing April 24th, 2015

Fast and accurate 3-D imaging technique to track optically trapped particles April 24th, 2015

A silver lining: UCSB researchers cradle silver nanoclusters inside synthetic DNA to create a programmed, tunable fluorescent array April 23rd, 2015

Discoveries

Heat makes electrons’ spin in magnetic superconductors April 26th, 2015

SEFCU, SUNY Poly CNSE Announce Winning Student-Led Teams in the 6th Annual $500,000 New York Business Plan Competition April 25th, 2015

Northwestern scientists develop first liquid nanolaser: Technology could lead to new way of doing 'lab on a chip' medical diagnostics April 25th, 2015

Fast and accurate 3-D imaging technique to track optically trapped particles April 24th, 2015

Announcements

Feynman Prize Winners Announced! April 26th, 2015

New ASTM Standards Will Help Educate Present and Future Nanotechnology Workforces April 26th, 2015

Heat makes electrons’ spin in magnetic superconductors April 26th, 2015

QD Vision Wins 2015 Bronze Edison Award for Color IQ™ Quantum Dot Technology April 26th, 2015

Environment

Nanoparticles Used to Improve Mechanical, Thermal Properties of Cellulose Fibers April 23rd, 2015

Young NTU Singapore spin-off clinches S$4.3 million joint venture with Chinese commercial giant March 23rd, 2015

New processing technology converts packing peanuts to battery components March 22nd, 2015

EU Funded PCATDES Project has completed its half-period with success March 19th, 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