Nanotechnology Now

Our NanoNews Digest Sponsors







Heifer International

Wikipedia Affiliate Button


Home > Press > Reducing ion exchange particles to nano-size shows big potential: Sometimes bigger isn't better

Abstract:
Researchers at the U.S. Department of Energy's Savannah River National Laboratory have successfully shown that they can replace useful little particles of monosodium titanate (MST) with even tinier nano-sized particles, making them even more useful for a variety of applications.

Reducing ion exchange particles to nano-size shows big potential: Sometimes bigger isn't better

Aiken, SC | Posted on January 30th, 2012

MST is an ion exchange material used to decontaminate radioactive and industrial wastewater solutions, and has been shown to be an effective way to deliver metals into living cells for some types of medical treatment. Typically, MST, and a modified form known as mMST developed by SRNL and Sandia National Laboratories, are in the form of fine powders, spherically-shaped particles about 1 to 10 microns in diameter (a micron is one-millionth of a meter).

"By making each particle smaller," says Dr. David Hobbs of SRNL, lead of the research project, "you increase the amount of surface area, compared to the overall volume of the particle. Since the particle surface is where reactions take place, you've increased the MST's working area." For example, a 10-nanometer particle has a surface area-to-volume ratio that is 1000 times that of a 10-micron particle. Thus, this project sought to synthesize titanate materials that feature nano-scale particle sizes (1 - 200 nm). After successfully synthesizing nanosize titanates, the team investigated and found that the smaller particles do indeed exhibit good ion exchange characteristics. They also serve as photocatalysts for the decomposition of organic contaminants and are effective platforms for the delivery of therapeutic metals.

Dr. Hobbs and his partners in the project examined three methods of producing nano-sized particles, resulting in three different shapes. One is a sol-gel method, similar to the process used to produce "normal" micron-sized MST particles, but using surfactants and dilute concentrations of reactive chemicals to control particle size. This method resulted in spherical particles about 100 - 150 nm in diameter.

A second method started with typical micron-sized particles, then delaminated and "unzipped" them to produce fibrous particles about 10 nm in diameter and 100 - 150 nm long. The third method, which had been previously reported in the scientific literature, was a hydrothermal technique that produced nanotubes with a diameter of about 10 nm and lengths of about 100 -500 nm.

The team had considerable expertise in working with MST, having previously modified it with peroxide to form mMST, which exhibits enhanced performance in removing certain contaminants from radioactive waste and delivering metals for medical treatment. Nanosize MST produced by all three methods was successfully converted to the peroxide-modified form. As with micron-sized titanates, the peroxide-modified nanosize titanates exhibit a yellow color. The intensity of the yellow color appeared less intense with the hydrothermally produced nanotubes, suggesting the chemically resistant surface of the nanotubes may limit conversion to mMST.

Testing confirmed that the materials function as effective ion exchangers. For example, the spherical nanoMST and nanotube samples and their respective peroxide-modified forms remove strontium and actinides from alkaline high-level waste radioactive waste. Under weakly acidic conditions, the nanosize titanates and peroxotitanates removed more than 90% of 17 different metal ions.

The "unzipped" titanates and their peroxide-modified forms proved to be particularly good photocatalysts for the decomposition of organic contaminants.

Screening in-vitro tests showed that both nano-size and micron-size metal-exchanged titanates inhibit the growth of a number of oral cancer and bacterial cell lines. The mechanism of inhibition is not known, but preliminary scanning electron microscopy results suggest that the titanates may be interacting directly with the wall of the nucleus to deliver sufficient metal ion concentration to the cell nucleus to inhibit cell replication.

In addition to Dr. Hobbs, the team included M. C. Elvington, M. H. Tosten, K. M. L. Taylor-Pashow of SRNL; J. Wataha of the University of Washington; and M. D. Nyman of Sandia National Laboratories.

This work was funded under SRNL's Laboratory Directed Research & Development program, which supports highly innovative and exploratory research aligned with the Laboratory's priorities.

####

About DOE/Savannah River National Laboratory
SRNL is DOE's applied research and development national laboratory at the Savannah River Site. SRNL puts science to work to support DOE and the nation in the areas of environmental stewardship, national security, and clean energy. The management and operating contractor for SRS and SRNL is Savannah River Nuclear Solutions, LLC.

For more information, please click here

Contacts:
Angeline French

803-725-2854

Copyright © DOE/Savannah River National Laboratory

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

Imaging

JPK reports on single molecule research at IISER Pune in India using AFM and CellHesion techniques May 21st, 2013

Kinks and curves at the nanoscale: New research shows 'perfect twin boundaries' are not so perfect May 20th, 2013

Beautiful "flowers" self-assemble in a beaker: Elaborate nanostructures blossom from a chemical reaction perfected at Harvard May 17th, 2013

Scientists capture first direct proof of Hofstadter butterfly effect May 17th, 2013

News and information

JPK reports on single molecule research at IISER Pune in India using AFM and CellHesion techniques May 21st, 2013

Imec and GLOBALFOUNDRIES collaborate to advance high-density memory technology: STT-MRAM offers enhanced performance and scalability for embedded and standalone applications May 21st, 2013

International survey supports need for built-in water protection on smartphones and tablets May 21st, 2013

Rice unveils method for tailoring optical processors: Arranging nanoparticles in geometric patterns allows for control of light with light May 21st, 2013

Chemistry

Penn engineers' nanoantennas improve infrared sensing May 20th, 2013

Laboratories

Kinks and curves at the nanoscale: New research shows 'perfect twin boundaries' are not so perfect May 20th, 2013

Artificial Forest for Solar Water-Splitting: Berkeley Lab Researchers Report First Fully Integrated Artificial Photosynthesis Nanosystem May 17th, 2013

Govt.-Legislation/Regulation/Funding/Policy

Nanoparticle Harnesses Powerful Radiation Therapy for Cancer May 20th, 2013

Microneedle-Delivered Nanoparticles Boost Antitumor Vaccines May 20th, 2013

New Nanopore Sensor Simplifies Analysis of Methylated DNA May 20th, 2013

Penn engineers' nanoantennas improve infrared sensing May 20th, 2013

Nanomedicine

Nanoparticle Delivers Large Protein Complex to Cancer Cell Nucleus May 20th, 2013

Protein 'Passport' Helps Nanoparticles Get Past Immune System May 20th, 2013

New Nanopore Sensor Simplifies Analysis of Methylated DNA May 20th, 2013

Elsevier Business Intelligence (EBI) to Host 'IN3 Medical Device 360 Boston,' June 24-26, 2013 May 20th, 2013

Discoveries

Rice unveils method for tailoring optical processors: Arranging nanoparticles in geometric patterns allows for control of light with light May 21st, 2013

Nanoparticle Harnesses Powerful Radiation Therapy for Cancer May 20th, 2013

Microneedle-Delivered Nanoparticles Boost Antitumor Vaccines May 20th, 2013

Competition in the Quantum World May 20th, 2013

Announcements

JPK reports on single molecule research at IISER Pune in India using AFM and CellHesion techniques May 21st, 2013

Imec and GLOBALFOUNDRIES collaborate to advance high-density memory technology: STT-MRAM offers enhanced performance and scalability for embedded and standalone applications May 21st, 2013

International survey supports need for built-in water protection on smartphones and tablets May 21st, 2013

Rice unveils method for tailoring optical processors: Arranging nanoparticles in geometric patterns allows for control of light with light May 21st, 2013

Tools

JPK reports on single molecule research at IISER Pune in India using AFM and CellHesion techniques May 21st, 2013

Penn engineers' nanoantennas improve infrared sensing May 20th, 2013

Kinks and curves at the nanoscale: New research shows 'perfect twin boundaries' are not so perfect May 20th, 2013

NanoInk, Inc. Assets To Be Sold May 18th, 2013

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








abbigliamento uomo
Computer Accessories
© Copyright 1999-2013 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE