Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Chemists Become Molecular Sculptors, Synthesizing Tiny, Molecular Traps: Tube-shaped traps carved from bottle-brush molecules could be used to capture and purify nanomaterials, proteins

An illustrated cross-section of a nanotube UB chemists created. The green structures are negatively charged carboxylic acid groups, which help trap positively charged particles.
An illustrated cross-section of a nanotube UB chemists created. The green structures are negatively charged carboxylic acid groups, which help trap positively charged particles.

Abstract:
Using clever but elegant design, University at Buffalo chemists have synthesized tiny, molecular cages that can be used to capture and purify nanomaterials.

Chemists Become Molecular Sculptors, Synthesizing Tiny, Molecular Traps: Tube-shaped traps carved from bottle-brush molecules could be used to capture and purify nanomaterials, proteins

Buffalo, NY | Posted on December 5th, 2011

Sculpted from a special kind of molecule called a "bottle-brush molecule," the traps consist of tiny, organic tubes whose interior walls carry a negative charge. This feature enables the tubes to selectively encapsulate only positively charged particles.

In addition, because UB scientists construct the tubes from scratch, they can create traps of different sizes that snare molecular prey of different sizes. The level of fine tuning possible is remarkable: In the Journal of the American Chemical Society, the researchers report that they were able to craft nanotubes that captured particles 2.8 nanometers in diameter, while leaving particles just 1.5 nanometers larger untouched.

These kinds of cages could be used, in the future, to expedite tedious tasks, such as segregating large quantum dots from small quantum dots, or separating proteins by size and charge.

"The shapes and sizes of molecules and nanomaterials dictate their utility for desired applications. Our molecular cages will allow one to separate particles and molecules with pre-determined dimensions, thus creating uniform building blocks for the fabrication of advanced materials," said Javid Rzayev, the UB assistant professor of chemistry who led the research.

"Just like a contractor wants tile squares or bricks to be the same size so they fit well together, scientists are eager to produce nanometer-size particles with the same dimensions, which can go a long way toward creating uniform and well-behaved materials," Rzayev said.

To create the traps, Rzayev and his team first constructed a special kind of molecule called a bottle-brush molecule. These resemble a round hair brush, with molecular "bristles" protruding all the way around a molecular backbone.

After stitching the bristles together, the researchers hollowed out the center of each bottle-brush molecule, leaving behind a structure shaped like a toilet paper tube.

The carving process employed simple but clever chemistry: When building their bottlebrush molecules, the scientists constructed the heart of each molecule using molecular structures that disintegrate upon coming into contact with water. Around this core, the scientists then attached a layer of negatively charged carboxylic acid groups.

To sculpt the molecule, the scientists then immersed it water, in effect hollowing the core. The resulting structure was the trap—a nanotube whose inner walls were negatively charged due to the presence of the newly exposed carboxylic acid groups.

To test the tubes' effectiveness as traps, Rzayev and colleagues designed a series of experiments involving a two-layered chemical cocktail.

The cocktail's bottom layer consisted of a chloroform solution containing the nanotubes, while the top layer consisted of a water-based solution containing positively charged dyes. (As in a tequila sunrise, the thinner, water-based solution floats on top of the denser chloroform solution, with little mixing.)

When the scientists shook the cocktail for five minutes, the nanotubes collided with and trapped the dyes, bringing the dyes into the chloroform solution. (The dyes, on their own, do not dissolve in chloroform.)

In similar experiments, Rzayev and his team were able to use the nanotubes to extract positively charged molecules called dendrimers from an aqueous solution. The nanotubes were crafted so that dendrimers with a diameter of 2.8 nanometers were trapped, while dendrimers that were 4.3 nanometers across were left in solution.

To remove the captured dendrimers from the nanotubes, the researchers simply lowered the pH of the chloroform solution, which shuts down the negative charge inside the traps and allows the captured particles to be released from their cages.

The research on nanotubes is part of a larger suite of studies Rzayev is conducting on bottle-brush molecules using a National Science Foundation CAREER award. His other work includes the fabrication of bottle-brush-based nanomembranes that could be adapted for water filtration, and the assembly of layered, bottle-brush polymers that reflect visible light like the wings of a butterfly do.

####

About University of Buffalo
The University at Buffalo is a premier research-intensive public university, a flagship institution in the State University of New York system and its largest and most comprehensive campus. UB's more than 28,000 students pursue their academic interests through more than 300 undergraduate, graduate and professional degree programs. Founded in 1846, the University at Buffalo is a member of the Association of American Universities.

For more information, please click here

Contacts:
Ellen Goldbaum

Twitter account egoldbaum
716-645-4605

Copyright © University of Buffalo

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

‘Oxford Instruments Young Nanoscientist India Award 2015’ to Prof. Arindam Ghosh April 20th, 2015

Nondestructive 3-D Imaging of Biological Cells with Sound April 20th, 2015

Advances in molecular electronics: Lights on -- molecule on: Researchers from Dresden and Konstanz succeed in light-controlled molecule switching April 20th, 2015

Yale-NUS, NUS and UT Austin researchers establish theoretical framework for graphene physics: Making strides towards using graphene to create new electronic devices April 20th, 2015

Chemistry

Protein Building Blocks for Nanosystems: Scientists develop method for producing bio-based materials with new properties April 17th, 2015

Major advance in artificial photosynthesis poses win/win for the environment: Berkeley Lab researchers perform solar-powered green chemistry with captured CO2 April 16th, 2015

How can you see an atom? (video) April 10th, 2015

Carnegie Mellon chemists create tiny gold nanoparticles that reflect nature's patterns April 9th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Better battery imaging paves way for renewable energy future April 20th, 2015

Quantum model reveals surface structure of water: National Physical Laboratory, IBM and Edinburgh University have used a new quantum model to reveal the molecular structure of water's liquid surface April 20th, 2015

Happily ever after: Scientists arrange protein-nanoparticle marriage: New biotech method could lead to development of HIV vaccine, targeted cancer treatment April 20th, 2015

New Biological Nano-Fertilizers Presented in Iran as Appropriate Replacements for Chemical Fertilizers April 18th, 2015

Molecular Nanotechnology

DWI scientists program the lifetime of self-assembled nanostructures April 9th, 2015

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Designer's toolkit for dynamic DNA nanomachines: Arm-waving nanorobot signals new flexibility in DNA origami March 27th, 2015

Monitoring the real-time deformation of carbon nanocoils under axial loading February 18th, 2015

Discoveries

Ethylene Nanosorbent, a Novel Product to Decrease Agricultural Waste April 20th, 2015

Quantum model reveals surface structure of water: National Physical Laboratory, IBM and Edinburgh University have used a new quantum model to reveal the molecular structure of water's liquid surface April 20th, 2015

Happily ever after: Scientists arrange protein-nanoparticle marriage: New biotech method could lead to development of HIV vaccine, targeted cancer treatment April 20th, 2015

Advances in molecular electronics: Lights on -- molecule on: Researchers from Dresden and Konstanz succeed in light-controlled molecule switching April 20th, 2015

Announcements

Happily ever after: Scientists arrange protein-nanoparticle marriage: New biotech method could lead to development of HIV vaccine, targeted cancer treatment April 20th, 2015

Nondestructive 3-D Imaging of Biological Cells with Sound April 20th, 2015

Advances in molecular electronics: Lights on -- molecule on: Researchers from Dresden and Konstanz succeed in light-controlled molecule switching April 20th, 2015

Yale-NUS, NUS and UT Austin researchers establish theoretical framework for graphene physics: Making strides towards using graphene to create new electronic devices April 20th, 2015

Water

Quantum model reveals surface structure of water: National Physical Laboratory, IBM and Edinburgh University have used a new quantum model to reveal the molecular structure of water's liquid surface April 20th, 2015

Dais Analytic Corporation Appoints Eliza Wang to Board of Directors: Company's Newest Director Brings Expertise in Commercial and Legal Matters Both in the United States and China; Joins on the Heels of Successful Business Development Trade Mission to China April 18th, 2015

Iranian Scientists Produce Magnetic Recyclable Photocatalyst to Purify Polluted Water April 8th, 2015

Water makes wires even more nano: Rice University lab extends meniscus-mask process to make sub-10 nanometer paths April 6th, 2015

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