Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

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

Searching for errors in the quantum world September 21st, 2018

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Nanobiotix: Update on Head and Neck Phase I/II Trial with NBTXR3 and Other program data presented at ImmunoRad 2018 September 20th, 2018

Govt.-Legislation/Regulation/Funding/Policy

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Researchers develop microbubble scrubber to destroy dangerous biofilms September 19th, 2018

Researchers managed to prevent the disappearing of quantum information September 14th, 2018

New photonic chip promises more robust quantum computers September 14th, 2018

Academic/Education

The Institute of Applied Physics at the University of Tsukuba near Tokyo in Japan uses Deben's ARM2 detector to better understand catalytic reaction mechanisms June 27th, 2018

Powering the 21st Century with Integrated Photonics: UCSB-Led Team Selected for Demonstration of a Novel Waveguide Platform Which is Transparent Throughout the MWIR and LWIR Spectral Bands June 19th, 2018

SUNY Poly Professor Eric Lifshin Selected for ‘Fellow of the Microanalysis Society’ Position for Significant Contributions to Microanalysis June 13th, 2018

Grand Opening of UC Irvine Materials Research Institute (IMRI) to Spotlight JEOL Center for Nanoscale Solutions: Renowned Materials Scientists to Present at the 1st International Symposium on Advanced Microscopy and Spectroscopy (ISAMS) April 18th, 2018

Nanomedicine

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Nanobiotix: Update on Head and Neck Phase I/II Trial with NBTXR3 and Other program data presented at ImmunoRad 2018 September 20th, 2018

NUS researchers invent new test kit for quick, accurate and low-cost screening of diseases: Test results are denoted by a color change and could be further analyzed by a smartphone app, making it attractive as a point-of-care diagnostic device September 19th, 2018

Announcements

Searching for errors in the quantum world September 21st, 2018

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

UT engineers develop first method for controlling nanomotors: Breakthrough for nanotechnology as UT engineers develop first method for switching the mechanical motion of nanomotors September 21st, 2018

Nanobiotix: Update on Head and Neck Phase I/II Trial with NBTXR3 and Other program data presented at ImmunoRad 2018 September 20th, 2018

Tools

Carbon nanodots do an ultrafine job with in vitro lung tissue: New experiments highlight the role of charge and size when it comes to carbon nanodots that mimic the effect of nanoscale pollution particles on the human lung. September 12th, 2018

Terahertz spectroscopy enters the single-molecule regime September 7th, 2018

Mirrorcle Demonstrates MEMS-based Programmable Light Source at CES and PW18 August 30th, 2018

Stress-free ALD from Picosun August 28th, 2018

Nanobiotechnology

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality September 21st, 2018

Nanobiotix: Update on Head and Neck Phase I/II Trial with NBTXR3 and Other program data presented at ImmunoRad 2018 September 20th, 2018

NUS researchers invent new test kit for quick, accurate and low-cost screening of diseases: Test results are denoted by a color change and could be further analyzed by a smartphone app, making it attractive as a point-of-care diagnostic device September 19th, 2018

Researchers develop microbubble scrubber to destroy dangerous biofilms September 19th, 2018

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project