Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Newly demonstrated capabilities of low-powered nanotweezers may benefit cellular-level studies

Experimental setup schematic showing laser source, microscope, and imaging detector and spectrometer. The inset illustrates the two different sample configurations that were explored; red arrows correspond to the input polarization directions and black arrows depict the propagation vector.
Experimental setup schematic showing laser source, microscope, and imaging detector and spectrometer. The inset illustrates the two different sample configurations that were explored; red arrows correspond to the input polarization directions and black arrows depict the propagation vector.

Abstract:
Using ultra-low input power densities, researchers at the University of Illinois at Urbana-Champaign have demonstrated for the first time how low-power "optical nanotweezers" can be used to trap, manipulate, and probe nanoparticles, including fragile biological samples.

Newly demonstrated capabilities of low-powered nanotweezers may benefit cellular-level studies

Urbana, IL | Posted on September 17th, 2012

"We already know that plasmonic nanoantennas enhance local fields by up to several orders of magnitude, and thus, previously showed that we can use these structures with a regular CW laser source to make very good optical tweezers," explains, Kimani Toussaint, Jr., assistant professor of mechanical science and engineering at Illinois. "This is exciting because, for the first time, we're showing that, the near-field optical forces can be enhanced even further, without doing anything extra in terms of fabrication, but rather simply by exploiting the high-peak powers associated with using a femtosecond (fs) optical source.

"We used an average power of 50 microwatts to trap, manipulate, and probe nanoparticles. This is 100x less power than what you would get from a standard laser pointer."

In their recent paper, "Femtosecond-pulsed plasmonic nanotweezers" published in the September 17 issue of Scientific Reports; doi:10.1038/srep00660), the researchers describe how a femtosecond-pulsed laser beam significantly augments the trapping strength of Au bowtie nanoantennas arrays (BNAs), and the first demonstration of use of femtosecond (fs) source for optical trapping with plasmonic nanotweezers.

"Our system operates at average power levels approximately three orders of magnitude lower than the expected optical damage threshold for biological structures, thereby making this technology very attractive for biological (lab-on-a-chip) applications such as cell manipulation," added Toussaint, who is also an affiliate faculty member in the Department of Bioengineering and the Department of Electrical and Computer Engineering. "This system offers increased local diagnostic capabilities by permitting the probing of the nonlinear optical response of trapped specimens, enabling studies of in vitro fluorescent-tagged cells, or viruses using a single line for trapping and probing rather than two or more laser lines."

"We present strong evidence that a fs source could actually augment the near-field optical forces produced by the BNAs, and most likely, other nanoantenna systems, as well. To our knowledge, this has never been demonstrated," said Brian Roxworthy, a graduate student in Toussaint's PROBE (Photonics Research of Bio/nano Environments) lab group and first author of the paper. According to Roxworthy, the demonstration of controlled particle fusing could be important for creating novel nanostructures, as well as for enhancing the local magnetic field response, which will be important for the field of magnetic plasmonics.

The paper also demonstrated enhancement of trap stiffness of up to 2x that of a comparable continuous-wave (CW) nanotweezers and 5x that of conventional optical tweezers that employ a fs source; successful trapping and tweezing of spherical particles ranging from 80-nm to 1.2-um in diameter, metal, dielectric, and both fluorescent and non- fluorescent particles; enhancement of two-photon fluorescent signal from trapped microparticles in comparison to the response without the presence of the BNAs; enhancement of the second-harmonic signal of ~3.5x for the combined nanoparticle-BNA system compared to the bare BNAs; and fusing of Ag nanoparticles to the BNAS.

####

For more information, please click here

Contacts:
Kimani C. Toussaint, Jr.
Department of Mechanical Science & Engineering
217/244-4088

Rick Kubetz
Engineering Communications Office
217/244-7716
writer/editor
University of Illinois at Urbana-Champaign

Copyright © University of Illinois at Urbana-Champaign

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

Three-dimensional graphene: Experiment at BESSY II shows that optical properties are tuneable May 24th, 2017

Leti to Demo 1st Wireless UNB Transceiver for ‘Massive Internet of Things’ at RFIC 2017 and IMS 2017: Leti Will also Present Three Papers & Two Workshops on 5G Communications IC Design, from RF to mm-Wave, During IMS 2017 and RFIC 2017 in Hawaii May 24th, 2017

GLOBALFOUNDRIES and Chengdu Partner to Expand FD-SOI Ecosystem in China: More than $100M investment to establish a center of excellence for FDXTM FD-SOI design May 23rd, 2017

Zap! Graphene is bad news for bacteria: Rice, Ben-Gurion universities show laser-induced graphene kills bacteria, resists biofouling May 22nd, 2017

Discoveries

Three-dimensional graphene: Experiment at BESSY II shows that optical properties are tuneable May 24th, 2017

Zap! Graphene is bad news for bacteria: Rice, Ben-Gurion universities show laser-induced graphene kills bacteria, resists biofouling May 22nd, 2017

Sensors detect disease markers in breath May 19th, 2017

Graphene-nanotube hybrid boosts lithium metal batteries: Rice University prototypes store 3 times the energy of lithium-ion batteries May 19th, 2017

Announcements

Three-dimensional graphene: Experiment at BESSY II shows that optical properties are tuneable May 24th, 2017

Leti to Demo 1st Wireless UNB Transceiver for ‘Massive Internet of Things’ at RFIC 2017 and IMS 2017: Leti Will also Present Three Papers & Two Workshops on 5G Communications IC Design, from RF to mm-Wave, During IMS 2017 and RFIC 2017 in Hawaii May 24th, 2017

GLOBALFOUNDRIES and Chengdu Partner to Expand FD-SOI Ecosystem in China: More than $100M investment to establish a center of excellence for FDXTM FD-SOI design May 23rd, 2017

Zap! Graphene is bad news for bacteria: Rice, Ben-Gurion universities show laser-induced graphene kills bacteria, resists biofouling May 22nd, 2017

Tools

Plasmon-powered upconversion nanocrystals for enhanced bioimaging and polarized emission: Plasmonic gold nanorods brighten lanthanide-doped upconversion superdots for improved multiphoton bioimaging contrast and enable polarization-selective nonlinear emissions for novel nanoscal May 19th, 2017

The brighter side of twisted polymers: Conjugated polymers designed with a twist produce tiny, brightly fluorescent particles with broad applications May 16th, 2017

Racyics Launches ‘makeChip’ Design Service Platform for GLOBALFOUNDRIES’ 22FDX® Technology: Racyics will provide IP and design services as a part of the foundry’s FDXcelerator™ Partner Program May 11th, 2017

UnitySC Announces Wafer Thinning Inspection System; Win from Power Semiconductor IDM for Automotive: Leading IDM Selects New 4See Series Automated Defect Inspection Platform for Power Semiconductor Automotive Applications May 11th, 2017

Photonics/Optics/Lasers

Zap! Graphene is bad news for bacteria: Rice, Ben-Gurion universities show laser-induced graphene kills bacteria, resists biofouling May 22nd, 2017

Plasmon-powered upconversion nanocrystals for enhanced bioimaging and polarized emission: Plasmonic gold nanorods brighten lanthanide-doped upconversion superdots for improved multiphoton bioimaging contrast and enable polarization-selective nonlinear emissions for novel nanoscal May 19th, 2017

Gas gives laser-induced graphene super properties: Rice University study shows inexpensive material can be superhydrophilic or superhydrophobic May 15th, 2017

Researchers develop transistors that can switch between two stable energy states May 9th, 2017

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