Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Look at Mie!

From left, Rice graduate students Sergio Dominguez-Medina, Liane Slaughter and Alexei Tcherniak, co-authors (with Stephan Link and Ji Won Ha) of a new paper investigating the plasmonic properties of nanoparticles as they relate to a century-old theory. Courtesy Jeff Fitlow.
From left, Rice graduate students Sergio Dominguez-Medina, Liane Slaughter and Alexei Tcherniak, co-authors (with Stephan Link and Ji Won Ha) of a new paper investigating the plasmonic properties of nanoparticles as they relate to a century-old theory. Courtesy Jeff Fitlow.

Abstract:
Rice team tests century-old calculations

By Mike Williams, Rice News Staff

Look at Mie!

Houston, TX | Posted on March 13th, 2010

Calculations are fine, but seeing is believing. That's the thought behind a new paper by Rice University students who decided to put to the test calculations made more than a century ago.

In 1908, the German physicist Gustav Mie came up with an elegant set of equations to describe the interaction of electromagnetic waves with a spherical metal particle. The theory has been a touchstone ever since for researchers seeking to quantify how nanoscale plasmonic particles scatter radiation.

"The Mie theory is used extensively whenever you deal with nanoparticles and their optical properties," said Alexei Tcherniak, a Rice graduate student and primary author of the new paper in the online edition of Nano Letters this month. "That's the foundation of every calculation."

Tcherniak and Stephan Link, a Rice assistant professor of chemistry and electrical and computer engineering, co-authored the paper with former graduate student Ji Won Ha and current Rice graduate students Liane Slaughter and Sergio Dominguez-Medina.

Better characterization of single nanoparticles is important to researchers pursuing microscopic optical sensors, subwavelength "super lenses," catalysis and photothermal cancer therapies that use nanoparticles.

"Since technology is moving toward single-particle detection, we wanted to see whether Mie's predictions would hold," Tcherniak said. "Average properties fall exactly on the predictions of Mie theory. But we show that individual particles deviate quite a bit."

Particles that differ in size can return similar signals because they vary in shape and orientation on the substrate, with which they also interact. Mie's theory, developed for spherical particles in solution long before the advent of single-particle spectroscopy, did not consider these factors.

The project began as a sideline in the students' attempt to track single nanoparticles in solution. It became their primary focus when they realized the scope of the task, which involved analyzing five sets of gold particles ranging from 51 to 237 nanometers wide - the "biologically relevant" sizes, Tcherniak explained.

Each set of particles was photographed with a scanning electron microscope and then analyzed for its absorption and scattering properties via single-particle photothermal imaging and laser dark-field scattering.

It was tedious, they admitted.

"When you need to find a particle 50 nanometers across on a sample that is 5-by-5 millimeters, you're looking for a needle in a haystack," Tcherniak said. Slaughter and Dominguez-Medina nodded in agreement and recalled a summer of long days categorizing hundreds of particles -- enough "to get all those points on the graph."

They used a couple of strategies to locate particles. One was to put micron-scale grid coordinates on the glass slide containing nanoparticle samples. "That let us know roughly where they were," Tcherniak said.

Another involved applying a bit of astronomy to their microscopy. They found themselves looking for "constellations" in the patterns of specks. "We started saying, 'Oh, that looks like a nose. Do we have a nose anywhere else?'" Slaughter said. "We were so tired; the names might not have been very good."

But their results are.

"Mie theory was around long before anyone knew about nanoparticles, so it's a neat thing to be able to test it," said Link of his students' work. "This is important because they really put together the building blocks that will enable scientists to look at more complex structures. This was not an easy job."

The National Science Foundation, the Robert A. Welch Foundation and 3M supported the research.


####

About Rice University
Rice has from its inception been dedicated to three missions: educating and preparing outstanding students for diverse careers and lives; contributing to the advancement of knowledge across a wide range of fields; and being of service to our city, our state, our nation, and our world. The Call to Conversation posed the question whether our current mission statement fully encompassed our ambitions, particularly our commitment as a research university to creating new knowledge and our obligation to train future leaders across a range of endeavors. It states: “The mission of Rice University, shaped largely by its founder and the first president, is to provide an unsurpassed undergraduate education in science, engineering, the arts, humanities, and social sciences; to produce internationally distinguished scholarship and research and excellent graduate education in carefully focused areas; to ensure that such an education remains affordable; to maintain the distinctive character of a community of learning that is relatively small in scale; and to serve the continuing educational needs of the larger community.”

For more information, please click here

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

UT Arlington physicist creates new nanoparticle for cancer therapy April 16th, 2014

Relieving electric vehicle range anxiety with improved batteries: Lithium-sulfur batteries last longer with nanomaterial-packed cathode April 16th, 2014

Aerotech X-Y ball-screw stage for economical high performance Planar positioning April 16th, 2014

Energy Research Facility Construction Project at Brookhaven Lab Wins U.S. Energy Secretary's Achievement Award April 16th, 2014

Govt.-Legislation/Regulation/Funding/Policy

UT Arlington physicist creates new nanoparticle for cancer therapy April 16th, 2014

Relieving electric vehicle range anxiety with improved batteries: Lithium-sulfur batteries last longer with nanomaterial-packed cathode April 16th, 2014

Energy Research Facility Construction Project at Brookhaven Lab Wins U.S. Energy Secretary's Achievement Award April 16th, 2014

Targeting cancer with a triple threat: MIT chemists design nanoparticles that can deliver three cancer drugs at a time April 15th, 2014

Academic/Education

Director Wally Pfister joins UC Berkeley neuroengineers to discuss the science behind ‘Transcendence’ April 7th, 2014

First annual science week highlights STEM pipeline and partnerships: UB, SUNY Buffalo State and ECC team up with the City of Buffalo and its schools for April 7-11 events April 3rd, 2014

Global 450 consortium announces new general manager of internal operations: TSMC’s Cheng-Chung Chien Receives Unanimous Support, Brings History of Innovation and Efficiency to Global Consortium of Companies Driving Industry Transition to 450mm Wafer Technology March 26th, 2014

NanoTecNexus to Host "Chemistry of Wine" Fundraiser in Support of STEM Education - Collaborations Key to Success - March 20th, 2014

Nanomedicine

UT Arlington physicist creates new nanoparticle for cancer therapy April 16th, 2014

Nanobiotix Appoints Thierry Otin as Head of Manufacturing and Supply April 15th, 2014

PAM-XIAMEN Offers UV LED wafer April 15th, 2014

Nanocrystalline cellulose modified into an efficient viral inhibitor April 15th, 2014

Announcements

UT Arlington physicist creates new nanoparticle for cancer therapy April 16th, 2014

Relieving electric vehicle range anxiety with improved batteries: Lithium-sulfur batteries last longer with nanomaterial-packed cathode April 16th, 2014

Aerotech X-Y ball-screw stage for economical high performance Planar positioning April 16th, 2014

Energy Research Facility Construction Project at Brookhaven Lab Wins U.S. Energy Secretary's Achievement Award April 16th, 2014

Tools

Aerotech X-Y ball-screw stage for economical high performance Planar positioning April 16th, 2014

Malvern reports on the publication of the 1000th peer-reviewed paper to cite NanoSight’s Nanoparticle Tracking Analysis, NTA April 16th, 2014

JPK announces expansion of its global sales and service activities in China and USA April 15th, 2014

Affordable High Precision XY Nanopositioning Piezo Stage April 15th, 2014

Nanobiotechnology

Targeting cancer with a triple threat: MIT chemists design nanoparticles that can deliver three cancer drugs at a time April 15th, 2014

Biologists Develop Nanosensors to Visualize Movements and Distribution of Plant Stress Hormone April 15th, 2014

In latest generation of tiny biosensors, size isn't everything: UCLA researchers overturn conventional wisdom on nanowire-based diagnostic devices April 11th, 2014

Virus structure inspires novel understanding of onion-like carbon nanoparticles April 10th, 2014

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 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE