Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International

Wikipedia Affiliate Button

Home > Press > Illinois researchers combine weak chemical forces to strengthen a novel imaging technology

Image created by Janet Sinn-Hanlon, DesignGroup@VetMed, University of Illinois
Image created by Janet Sinn-Hanlon, DesignGroup@VetMed, University of Illinois

Abstract:
When Associate Professor of Chemical and Biomolecular Engineering Hyunjoon Kong, graduate student Cartney Smith, and colleagues set out to improve MR imaging (MRI), they turned current contrast agent technology on its head—or rather, they turned it inside out. The new compound they designed in collaboration with Roger Adams Professor of Chemistry Steven C. Zimmerman is not only more effective, but also self-assembling. Kong is a member of the Regenerative Biology and Tissue Engineering research theme at the Institute for Genomic Biology.

Illinois researchers combine weak chemical forces to strengthen a novel imaging technology

Urbana, IL | Posted on May 21st, 2014

When doctors perform an MRI, they administer a contrast agent: a chemical that, when injected into the bloodstream or ingested by the patient just before the MRI, improves the clarity of structures or organs in the resulting image. One common class of contrast agent, often used for imaging of blood vessels and internal bleeding, contains gadolinium, a rare-earth metal.

Recently, biomedical researchers have found ways to increase the effectiveness of certain contrast agents by associating them with nanoparticles. The contrast agent being used is packaged inside or bonded to the surface of microscopic particles, which can be designed to target certain regions of the body or prolong the agent's activity.

Researchers are now exploring the multipurpose use of nanoparticles. If particles could be loaded with several types of contrast agents or dyes instead of one, or a contrast agent along with another type of diagnostic aid or a medication, doctors could more efficiently test for and treat conditions, and limit the number of injections received by patients.

Just like toddlers sharing a new toy, though, compounds packaged together into a nanoparticle cannot always play well together. For example, contrast agents may bind to other chemicals, reducing their effectiveness. In addition, when contrast agents are enclosed inside a nanoparticle, they may not work as well. Attempts to attach agents to the outer surface of nanoparticles via covalent formation are also problematic, as they can negatively affect the activity of the nanoparticles or the compounds that they carry.

Kong, Smith and colleagues tackled these challenges by using interactions between naturally occurring biomolecules as a guide. Many types of proteins are strongly attached to cell membranes not by covalent bonds, but by the sum of multiple weaker forces—the attraction of positive and negative charges, and the tendency of non-polar (oil-like) substances to seek each other and avoid water.

The group hypothesized that the same types of forces could be used to attach a contrast agent to the surface of a type of nanoparticle called a liposome, which resembles a little piece of cell membrane in the shape of a tiny bubble. The researchers designed a "fastener" molecule, DTPA-chitosan-g-C18, that is charged, attracting it to the liposome and binding it to the contrast agent gadolinium. A nonpolar region anchors it to the liposome membrane.

In a series of experiments reported in a recent ACS Nano article (DOI: 10.1021/nn4026228), Kong and others demonstrated that their fastener molecule readily inserted itself into the membrane of pre-made liposomes. Gadolinium stably associated with the modified nanoparticles in solution, and experiments in animal models showed that these nanoparticles produced clear diagnostic images.

"The strategy works like Velcro on a molecular level to adhere functional units to the outer leaflet of a liposome," said Smith, who was first author on the study. "This work represents a new material design strategy that is scalable and easily implemented. The development of improved contrast agents has the potential to directly impact patients' lives by detecting damaged blood vessels."

One of the difficulties of working with liposomes is their tendency to degrade inside the body. When the fastener-loaded liposomes degraded, some of the efficacy of the gadolinium was lost. In a second study published in Langmuir (DOI: 10.1021/la500412r), Kong and Smith developed a process for chemically cross-linking the components of the nanoparticle that prolonged the life of the nanoparticles in biological conditions.

The work reported in ACS Nano was a collaboration among Kong, Smith, Zimmerman, and others at the University of Illinois, as well as Dr. Sanjay Misra and researchers at the Mayo Clinic. Both studies were supported by funding from the National Institutes of Health, as well as the University of Illinois Center for Advanced Study.

Written By:
Claudia Lutz. Photos by L. Brian Stauffer and Janet Sinn-Hanlon.

####

For more information, please click here

Contacts:
Nicholas Vasi

Copyright © University of Illinois at Urbana-Champaign

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 Links

Download article:

Related News Press

News and information

Artificial photosynthesis transforms carbon dioxide into liquefiable fuels May 22nd, 2019

Neutrons unlock the secrets of limoncello May 21st, 2019

Machine learning speeds modeling of experiments aimed at capturing fusion energy on Earth May 17th, 2019

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

Generating high-quality single photons for quantum computing: New dual-cavity design emits more single photons that can carry quantum information at room temperature May 17th, 2019

Chemistry

Neutrons unlock the secrets of limoncello May 21st, 2019

Army discovery opens path to safer batteries May 10th, 2019

Coal could yield treatment for traumatic injuries: Rice, Texas A&M, UTHealth scientists discover coal-derived ‘dots’ are effective antioxidant April 25th, 2019

Imaging

New Argonne coating could have big implications for lithium batteries May 14th, 2019

Better microring sensors for optical applications May 10th, 2019

Govt.-Legislation/Regulation/Funding/Policy

Machine learning speeds modeling of experiments aimed at capturing fusion energy on Earth May 17th, 2019

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

New way to beat the heat in electronics: Rice University lab's flexible insulator offers high strength and superior thermal conduction May 16th, 2019

New Argonne coating could have big implications for lithium batteries May 14th, 2019

Nanomedicine

Better microring sensors for optical applications May 10th, 2019

New efficient way to engineer nanostructures mimicking natural immune response complexes: Novel method to engineer large multi-antibody-like nanostructures using DNA nanotechnology; the results demonstrate the potential for assembly of multiple proteins and also other materials t May 10th, 2019

Nanotubes enable travel of Huntington's protein: Rhes protein makes its own road to convey disease drivers May 10th, 2019

A cautionary tale for researchers working on selective drug delivery May 9th, 2019

Discoveries

Artificial photosynthesis transforms carbon dioxide into liquefiable fuels May 22nd, 2019

Neutrons unlock the secrets of limoncello May 21st, 2019

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

New surface treatment could improve refrigeration efficiency: A slippery surface for liquids with very low surface tension promotes droplet formation, facilitating heat transfer May 17th, 2019

Announcements

Artificial photosynthesis transforms carbon dioxide into liquefiable fuels May 22nd, 2019

Neutrons unlock the secrets of limoncello May 21st, 2019

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

New surface treatment could improve refrigeration efficiency: A slippery surface for liquids with very low surface tension promotes droplet formation, facilitating heat transfer May 17th, 2019

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Artificial photosynthesis transforms carbon dioxide into liquefiable fuels May 22nd, 2019

Machine learning speeds modeling of experiments aimed at capturing fusion energy on Earth May 17th, 2019

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

Generating high-quality single photons for quantum computing: New dual-cavity design emits more single photons that can carry quantum information at room temperature May 17th, 2019

Research partnerships

Manipulating atoms one at a time with an electron beam: New method could be useful for building quantum sensors and computers May 17th, 2019

New Argonne coating could have big implications for lithium batteries May 14th, 2019

Sculpting Super-Fast Light Pulses: NIST Nanopillars Shape Light Precisely for Practical Applications May 3rd, 2019

Exploring New Ways to Control Thermal Radiation April 29th, 2019

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