Navigation Links
Purifying nanorods: Big success with tiny cleanup

HOUSTON, Sept. 22, 2008 -- Chemists at Rice University have discovered a novel method to produce ultra-pure gold nanorods -- tiny, wand-like nanoparticles that are being studied in dozens of labs worldwide for applications as broad as diagnosing disease and improving electronic viewscreens.

"The content of high-aspect-ratio gold nanorods produced by today's best synthetic methods is only about 20 percent," said lead researcher Eugene Zubarev, assistant professor of chemistry at Rice. "A nanoparticle's shape plays a crucial role in determining many of its physical and chemical properties, so when four out of five particles in a batch are the wrong shape, it's a tremendous impediment to practical applications and commercialization."

Zubarev and graduate student Bishnu Khanal's new purification method filters more than 99 percent of impurities from gold nanorods. The research is available online and will appear in the Sep. 25 issue of the Journal of the American Chemical Society. It's an example of the sort of processing and synthesis methods that the federal government called for last year in a key report that examined the economic potential of nanotechnology.

Nanotechnology refers to a set of tools and methods that scientists use to see, measure and control matter with exquisite control, sometimes moving just one atom at a time. By building materials from the bottom up, at the molecular level, scientists can tailor particles that interact in precise ways with living cells, light waves, drugs and other chemicals. The word nanotechnology refers to the nanometer, a unit of length equal to one-billionth of a meter.

The nanorods studied by Zubarev and Khanal are about 25 nanometers in diameter and about 250 nanometers long. In comparison, a single gold atom is only about one third of a nanometer in diameter. Thus, the cross-section of each nanorod is made of just a few thousand gold atoms. Because of their long, narrow shape, the nanorods interact with light, electricity and magnetic fields differently than spheres or discs containing the same number of atoms.

Tuning the shape- and size-specific properties of nanoparticles is critically important for the emerging U.S. nanotechnology industry. The U.S. has invested more than $8 billion in nanotechnology research and development since 2000, and the National Science Foundation estimates the global market for nanotechnology products will be about $1 trillion by 2015. In its 2007 strategic plan, the National Nanotechnology Initiative, which oversees U.S. nanotechnology research spending, pointed to the critical need for synthesis and processing techniques that yield high-quality, pure nanomaterials.

Nanorods are produced by mixing several chemicals in a precise, multi-step process. The method also produces gold nanoparticles of other shapes, including spheres and flattened sheets called platelets. Researchers had previously found a way to remove the spheres; the nanorods and platelets were allowed to gradually sink to the bottom of the mixture, and the spheres were siphoned away.

While conducting research on a different project, Zubarev and Khanal noticed that the nanorods and platelets in the remaining solution shrank when a solution of gold ions was added. They found that the platelets shrank much faster than the nanorods, and by tuning the process they discovered they could filter out the platelets and produce nanorod solutions that were more than 99 percent pure.


Contact: Jade Boyd
Rice University

Related biology technology :

1. Possible new approach to purifying drinking water
2. Tengion Featured as Model of Innovation and Success at 35th Anniversary Celebration of the National Venture Capital Association
3. ESBATech Announces Successful Completion of Phase I Clinical Study for Lead Antibody Fragment in Ophthalmic Indications
4. Neptune Technologies successfully completes up to $8.5 million debt financing with Desjardins Group
5. SAFC Hitech(TM) Successfully Demonstrates Device-Quality GST Precursors For Phase Change Memory Applications
6. CoreValve Successfully Treats the First Pacific Rim Patients with Its ReValving System for Percutaneous Aortic Valve Replacement : Australia/New Zealand Regulatory-Cleared Evaluation Registry is Expected to Lead to Market Clearance for These Countries
7. Spherics, Inc. Successful Bidder May Make MHRA Submission
8. Spherics, Inc. Successful Bidder May Make NDA Submission
9. Renowned NJ-Based Video Assisted Thoracic Surgery (VATS) Team Completes 5,000th Successful Procedure
10. Cantel Medical Announces Management Succession at Crosstex Healthcare Disposables Subsidiary
11. Senesco Technologies Announces Successful Completion of First Milestone Related to Agreement with Bayer CropScience
Post Your Comments:
(Date:11/25/2015)... Studies reveal the differences in species of bacteria ... for more effective treatment for one of the most commonly ... --> --> Gum disease is one ... relatively little was understood about the bacteria associated with it ... researchers from the WALTHAM Centre for Pet Nutrition together with ...
(Date:11/25/2015)... DIEGO , Nov. 25, 2015 Orexigen® ... management will participate in a fireside chat discussion at ... New York . The discussion is scheduled ... .  A replay will be ... Media Contact:McDavid Stilwell  , Julie NormartVP, Corporate Communications ...
(Date:11/24/2015)... Calif. , Nov. 24, 2015 Cepheid ... will be speaking at the following conference, and invited ... New York, NY      Tuesday, December 1, 2015 ... New York, NY      Tuesday, December 1, 2015 ... Jaffray Healthcare Conference, New York, NY ...
(Date:11/24/2015)... QUEBEC CITY , Nov. 24, 2015 /PRNewswire/ - ... the request of IIROC on behalf of the Toronto ... this news release there are no corporate developments that ... price. --> --> ... --> . --> Aeterna Zentaris ...
Breaking Biology Technology:
(Date:10/27/2015)... 27, 2015 In the present market scenario, ... for various industry verticals such as banking, healthcare, defense, ... growing demand for secure & simplified access control and ... as hacking of bank accounts, misuse of users, , ... as PC,s, laptops, and smartphones are expected to provide ...
(Date:10/27/2015)... SAN JOSE, Calif. , Oct. 27, 2015 /PRNewswire/ ... human interface solutions, today announced that Google has adopted ... family of touch controller solutions to power its newest ... Nexus 6P by Huawei. --> ... ecosystem partners like Google to provide strategic collaboration in ...
(Date:10/26/2015)... PALO ALTO, Calif. and LAS ... – Nok Nok Labs , an innovator in ... FIDO Alliance , today announced the launch of its ... the first unified platform enabling organizations to use standards-based ... authentication. The Nok Nok S3 Authentication Suite is ideal ...
Breaking Biology News(10 mins):