Featured Research

from universities, journals, and other organizations

Researchers find way to align gold nanorods on a large scale

Date:
August 18, 2011
Source:
North Carolina State University
Summary:
Researchers have developed a simple, scalable way to align gold nanorods, particles with optical properties that could be used for emerging biomedical imaging technologies.

Researchers from North Carolina State University have developed a simple, scalable way to align gold nanorods, particles with optical properties that could be used for emerging biomedical imaging technologies.

Aligning gold nanorods is important because they respond to light differently, depending on the direction in which the nanorods are pointed. To control the optical response of the nanorods, researchers want to ensure that all of the nanorods are aligned.

The NC State researchers developed a way to align the gold nanorods using electrospun polymer "nano/microfibers." Electrospinning is a way of producing fibers, with a liquid polymer being discharged from a needle and then solidifying. The researchers produced fibers as thin as 40 nanometers (nm) in diameter and as thick as three microns in diameter -- thus, nano/microfibers.

The researchers mixed the gold nanorods into the polymer solution, causing them to be incorporated directly into the polymer. The nanorods align when the fibers form. The force experienced by the liquid polymer as it is emitted from the electrospinning needle creates "streamlines" in the polymer solution.

"The nanorods are forced into alignment with these streamlines, like logs in a river that swing into alignment with the current," says Dr. Joe Tracy, an assistant professor of materials science and engineering at NC State and co-author of a paper describing the study. "And as the polymer solidifies, the aligned nanorods are locked into place."

"Electrospinning efforts at NC State are world-class and have yielded a wide range of novel and functional materials," adds Dr. Rich Spontak, a professor of chemical and biomolecular engineering and materials science and engineering at NC State and paper co-author. "What makes this result truly exciting is that the alignment is multiscale, or simultaneously achieved at different length scales. The nanorods are aligned at nanoscale dimensions, whereas the fibers are aligned at larger length scales."

This approach has been used in the past to align other kinds of nanorods, but this is the first time it has been done with gold nanorods. "To the best of our knowledge, this is also the first time nanorods of this size have been aligned in electrospun fibers," Tracy says, referring to the fact that the study focused on relatively short nanorods.

Specifically, the researchers used nanorods with an aspect ratio of 3.1. For example, that means that a nanorod measuring 10 nm wide would be 31 nm long. The nanorods in the study were approximately 49 nm long.

This aspect ratio is important, because it affects the way the nanorods interact with light -- and, therefore, their optical properties.


Story Source:

The above story is based on materials provided by North Carolina State University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kristen E. Roskov, Krystian A. Kozek, Wei-Chen Wu, Raghav K. Chhetri, Amy L. Oldenburg, Richard J. Spontak, Joseph B. Tracy. Long-Range Alignment of Gold Nanorods in Electrospun Polymer Nano/Microfibers. Langmuir, 2011; 110811133320019 DOI: 10.1021/la2021066

Cite This Page:

North Carolina State University. "Researchers find way to align gold nanorods on a large scale." ScienceDaily. ScienceDaily, 18 August 2011. <www.sciencedaily.com/releases/2011/08/110817092222.htm>.
North Carolina State University. (2011, August 18). Researchers find way to align gold nanorods on a large scale. ScienceDaily. Retrieved September 22, 2014 from www.sciencedaily.com/releases/2011/08/110817092222.htm
North Carolina State University. "Researchers find way to align gold nanorods on a large scale." ScienceDaily. www.sciencedaily.com/releases/2011/08/110817092222.htm (accessed September 22, 2014).

Share This



More Matter & Energy News

Monday, September 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: SpaceX Rocket Carries 3-D Printer to Space

Raw: SpaceX Rocket Carries 3-D Printer to Space

AP (Sep. 22, 2014) — A SpaceX Rocket launched from Cape Canaveral, carrying a custom-built 3-D printer into space. NASA envisions astronauts one day using the printer to make their own spare parts. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Thousands March in NYC Over Climate Change

Thousands March in NYC Over Climate Change

AP (Sep. 21, 2014) — Accompanied by drumbeats, wearing costumes and carrying signs, thousands of demonstrators filled the streets of Manhattan and other cities around the world on Sunday to urge policy makers to take action on climate change. (Sept. 21) Video provided by AP
Powered by NewsLook.com
What This MIT Sensor Could Mean For The Future Of Robotics

What This MIT Sensor Could Mean For The Future Of Robotics

Newsy (Sep. 20, 2014) — MIT researchers developed a light-based sensor that gives robots 100 times the sensitivity of a human finger, allowing for "unprecedented dexterity." Video provided by Newsy
Powered by NewsLook.com
MIT BioSuit A New Take On Traditional Spacesuits

MIT BioSuit A New Take On Traditional Spacesuits

Newsy (Sep. 19, 2014) — The MIT BioSuit could be an alternative to big, bulky traditional spacesuits, but the concept needs some work. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins