Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Light touch keeps a grip on delicate nanoparticles

NIST researchers' new approach to trapping nanoparticles uses a control and feedback system that nudges them only when needed, lowering the average intensity of the beam and increasing the lifetime of the nanoparticles while reducing their tendency to wander. On the left, 100-nanometer gold nanoparticles quickly escape from a static trap while gold nanoparticles trapped using the NIST method remained strongly confined.

Credit: NIST
NIST researchers' new approach to trapping nanoparticles uses a control and feedback system that nudges them only when needed, lowering the average intensity of the beam and increasing the lifetime of the nanoparticles while reducing their tendency to wander. On the left, 100-nanometer gold nanoparticles quickly escape from a static trap while gold nanoparticles trapped using the NIST method remained strongly confined.

Credit: NIST

Abstract:
Using a refined technique for trapping and manipulating nanoparticles, researchers at the National Institute of Standards and Technology (NIST) have extended the trapped particles' useful life more than tenfold.* This new approach, which one researcher likens to "attracting moths," promises to give experimenters the trapping time they need to build nanoscale structures and may open the way to working with nanoparticles inside biological cells without damaging the cells with intense laser light.

Light touch keeps a grip on delicate nanoparticles

Gaithersburg, MD | Posted on May 4th, 2012

Scientists routinely trap and move nanoparticles in a solution with "optical tweezers"—a laser focused to a very small point. The tiny dot of laser light creates a strong electric field, or potential well, that attracts particles to the center of the beam. Although the particles are attracted into the field, the molecules of the fluid they are suspended in tend to push them out of the well. This effect only gets worse as particle size decreases because the laser's influence over a particle's movement gets weaker as the particle gets smaller. One can always turn up the power of the laser to generate a stronger electric field, but doing that can fry the nanoparticles too quickly to do anything meaningful with them—if it can hold them at all.

NIST researchers' new approach uses a control and feedback system that nudges the nanoparticle only when needed, lowering the average intensity of the beam and increasing the lifetime of the nanoparticle while reducing its tendency to wander. According to Thomas LeBrun, they do this by turning off the laser when the nanoparticle reaches the center and by constantly tracking the particle and moving the tweezers as the particle moves.

"You can think of it like attracting moths in the dark with a flashlight," says LeBrun. "A moth is naturally attracted to the flashlight beam and will follow it even as the moth flutters around apparently at random. We follow the fluttering particle with our flashlight beam as the particle is pushed around by the neighboring molecules in the fluid. We make the light brighter when it gets too far off course, and we turn the light off when it is where we want it to be. This lets us maximize the time that the nanoparticle is under our control while minimizing the time that the beam is on, increasing the particle's lifetime in the trap."

Using this method at constant average beam power, 100-nanometer gold particles remained trapped 26 times longer than had been seen in previous experiments. Silica particles 350 nanometers in diameter lasted 22 times longer, but with the average beam power reduced by 33 percent. LeBrun says that their approach should be able to be combined with other techniques to trap and hold even smaller nanoparticles for extended periods without damaging them.

"We're more than an order of magnitude ahead of where we were before," says LeBrun. "We now hope to begin building complex nanoscale devices and testing nanoparticles as sensors and drugs in living cells."

####

For more information, please click here

Contacts:
Mark Esser

301-975-8735

Copyright © National Institute of Standards and Technology (NIST)

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 Links

* A. Balijepalli, J. Gorman, S. Gupta and T. LeBrun. Significantly Improved Trapping Lifetime of Nanoparticles in an Optical Trap using Feedback Control. Nano Letters. April 10, 2012. Available online:

Related News Press

News and information

New Biological Nano-Fertilizers Presented in Iran as Appropriate Replacements for Chemical Fertilizers April 18th, 2015

Iranian Foodstuff, Agricultural Industries Welcome Nanotechnology Packaging Bags April 18th, 2015

Nanocomposites Play Effective Role in Production of Smart Fibers April 18th, 2015

Dais Analytic Corporation Appoints Eliza Wang to Board of Directors: Company's Newest Director Brings Expertise in Commercial and Legal Matters Both in the United States and China; Joins on the Heels of Successful Business Development Trade Mission to China April 18th, 2015

Laboratories

Oxford Instruments commissions high field outsert magnet system for the National High Magnetic Field Laboratory 32 Tesla magnet program April 17th, 2015

Long Island Capital Alliance Announces Participants for Brookhaven National Laboratory Technology Transfer Capital Forum on May 8: Keynote Speaker Dr. Doon Gibbs, Director of Brookhaven National Laboratory April 16th, 2015

Major advance in artificial photosynthesis poses win/win for the environment: Berkeley Lab researchers perform solar-powered green chemistry with captured CO2 April 16th, 2015

Promising future of quantum dots explored in conference: ‘20 Years of Quantum Dots at Los Alamos’ runs April 12-16 April 13th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Engineer improves rechargeable batteries with MoS2 nano 'sandwich' April 18th, 2015

New Biological Nano-Fertilizers Presented in Iran as Appropriate Replacements for Chemical Fertilizers April 18th, 2015

Beyond the lithium ion -- a significant step toward a better performing battery April 18th, 2015

Oxford Instruments commissions high field outsert magnet system for the National High Magnetic Field Laboratory 32 Tesla magnet program April 17th, 2015

Nanomedicine

Optical resonance-based biosensors designed for medical applications April 18th, 2015

Nanocomposites Play Effective Role in Production of Smart Fibers April 18th, 2015

Novel nanoparticles could save soldiers' lives after explosions April 15th, 2015

Nanoparticles at specific temperature stimulate antitumor response: Dartmouth researchers identify precise heat to boost immune system against cancer tumors April 14th, 2015

Sensors

Optical resonance-based biosensors designed for medical applications April 18th, 2015

MIT sensor detects spoiled meat: Tiny device could be incorporated into 'smart packaging' to improve food safety April 15th, 2015

Graphene pushes the speed limit of light-to-electricity conversion: Researchers from ICFO, MIT and UC Riverside have been able to develop a graphene-based photodetector capable of converting absorbed light into an electrical voltage at ultrafast timescales April 14th, 2015

Iranian Scientists Evaluate Dynamic Interaction between 2 Carbon Nanotubes April 14th, 2015

Discoveries

Optical resonance-based biosensors designed for medical applications April 18th, 2015

Iranian Foodstuff, Agricultural Industries Welcome Nanotechnology Packaging Bags April 18th, 2015

Nanocomposites Play Effective Role in Production of Smart Fibers April 18th, 2015

Protein Building Blocks for Nanosystems: Scientists develop method for producing bio-based materials with new properties April 17th, 2015

Announcements

New Biological Nano-Fertilizers Presented in Iran as Appropriate Replacements for Chemical Fertilizers April 18th, 2015

Iranian Foodstuff, Agricultural Industries Welcome Nanotechnology Packaging Bags April 18th, 2015

Nanocomposites Play Effective Role in Production of Smart Fibers April 18th, 2015

Dais Analytic Corporation Appoints Eliza Wang to Board of Directors: Company's Newest Director Brings Expertise in Commercial and Legal Matters Both in the United States and China; Joins on the Heels of Successful Business Development Trade Mission to China April 18th, 2015

Photonics/Optics/Lasers

Protein Building Blocks for Nanosystems: Scientists develop method for producing bio-based materials with new properties April 17th, 2015

Light in a spin: Researchers demonstrate angular accelerating light April 15th, 2015

Graphene pushes the speed limit of light-to-electricity conversion: Researchers from ICFO, MIT and UC Riverside have been able to develop a graphene-based photodetector capable of converting absorbed light into an electrical voltage at ultrafast timescales April 14th, 2015

Scientists create invisible objects without metamaterial cloaking April 14th, 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