Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Defining the Design Rules for Targeted Nanoparticles Used To Image Tumors

Abstract:
One of the challenges of using nanoparticles for imaging tumors during surgery is that there needs to be a tradeoff between the number of nanoparticles that target a tumor and the rapid clearance of any unbound nanoparticles from the body. A large number of nanoparticles sticking tightly to a tumor will provide a bright signal that can help a surgeon spot the edges of the malignant tissue, but only if the background signal from unbound nanoparticles - the ones circulating freely through the body - is not too high.

Defining the Design Rules for Targeted Nanoparticles Used To Image Tumors

Bethesda, MD | Posted on February 19th, 2010

Now, a team of investigators has developed a set of design rules that can optimize that tradeoff, producing nanoparticles that have the best chance of binding to a tumor but that will clear rapidly through the kidneys when they do not find their target. The team, led by John Frangioni, from the Beth Israel Deaconess Medical Center, and Moungi Bawendi, of the Massachusetts Institute of Technology and a member of the MIT-Harvard Center of Cancer Nanotechnology Excellence, published the results of their work in the journal Nature Nanotechnology.

In earlier work, the investigators had found that the kidneys efficiently filter out of the blood stream nanoparticles of approximately 5.5 nanometers (nm) in diameter and that are zwitterionic, that is they have both positive and negative charges on their surface. The researchers also developed ultrasmall, zwitterionic, brightly fluorescent nanoparticles consisting of a zinc-cadmium sulfide core surrounded by a cadmium selenide shell and a cysteine coating.

In this study, the investigators linked one of two tumor targeting agents to the cysteine coating and tested the ability of the two formulations to target tumors and yet be cleared from circulation. While the usual approach to developing targeted nanoparticles has been to add as large a number of targeting molecules as possible in order to increase the probability of sticking to the targeted tissue, the investigators found that they could only add between five and ten targeting molecules without increasing the overall size of the nanoparticle above the 5.5 nm cutoff. Of equal importance, they also found that nanoparticles prepared in this manner did not bind to blood stream proteins, which would have had the effect of increasing the overall size of the nanoparticles.

Tests in animals using cultured cells showed that using even relatively low numbers of targeting molecules produced nanoparticles capable of binding tightly to targeted tumor cells. Biodistribution studies showed that the nanoparticles accumulated in targeted tumors, where they could be imaged, but not in the liver, spleen, and lungs, tissues that often accumulate circulating nanoparticles. Unbound nanoparticles were excreted through the kidneys, as predicted, within 4 hours. Four-hour clearance is important because it means that in practice, a patient scheduled for tumor-removing surgery could receive a dose of the nanoparticles when first arriving at the hospital and that background levels of unbound nanoparticles would be close to zero by the time the surgeon needed to image labeled tumors.

This work, which is detailed in a paper titled "Design considerations for tumour-targeted nanoparticles," was supported in part by the NCI Alliance for Nanotechnology in Cancer, a comprehensive initiative designed to accelerate the application of nanotechnology to the prevention, diagnosis, and treatment of cancer. An abstract of this paper is available at the journal's website.

####

About NCI Alliance for Nanotechnology in Cancer
To help meet the goal of reducing the burden of cancer, the National Cancer Institute (NCI), part of the National Institutes of Health, is engaged in efforts to harness the power of nanotechnology to radically change the way we diagnose, treat and prevent cancer.

The NCI Alliance for Nanotechnology in Cancer is a comprehensive, systematized initiative encompassing the public and private sectors, designed to accelerate the application of the best capabilities of nanotechnology to cancer.

Currently, scientists are limited in their ability to turn promising molecular discoveries into benefits for cancer patients. Nanotechnology can provide the technical power and tools that will enable those developing new diagnostics, therapeutics, and preventives to keep pace with today’s explosion in knowledge.

For more information, please click here

Copyright © NCI Alliance for Nanotechnology in Cancer

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

Enhancing the sensing capabilities of diamonds with quantum properties: A simple method can give diamonds the special properties needed for quantum applications such as sensing magnetic fields September 24th, 2017

Quantum twisted Loong confirms the physical reality of wavefunctions September 23rd, 2017

Application of air-sensitive semiconductors in nanoelectronics: 2-D semiconductor gallium selenide in encapsulated nanoelectronic devices September 22nd, 2017

Researchers set time limit for ultrafast perovskite solar cells September 22nd, 2017

Possible Futures

Enhancing the sensing capabilities of diamonds with quantum properties: A simple method can give diamonds the special properties needed for quantum applications such as sensing magnetic fields September 24th, 2017

Application of air-sensitive semiconductors in nanoelectronics: 2-D semiconductor gallium selenide in encapsulated nanoelectronic devices September 22nd, 2017

Researchers set time limit for ultrafast perovskite solar cells September 22nd, 2017

DNA triggers shape-shifting in hydrogels, opening a new way to make 'soft robots' September 21st, 2017

Academic/Education

Two Scientists Receive Grants to Develop New Materials: Chad Mirkin and Monica Olvera de la Cruz recognized by Sherman Fairchild Foundation August 16th, 2017

Moving at the Speed of Light: University of Arizona selected for high-impact, industrial demonstration of new integrated photonic cryogenic datalink for focal plane arrays: Program is major milestone for AIM Photonics August 10th, 2017

Graduate Students from Across the Country Attend Hands-on NanoCamp: Prominent scientists Warren Oliver, Ph.D., and George Pharr, Ph.D., presented a weeklong NanoCamp for hand-picked graduate students across the United States July 26th, 2017

The Physics Department of Imperial College, London, uses the Quorum Q150T to deposit metals and ITO to make plasmonic sensors and electric contact pads July 13th, 2017

Nanomedicine

Do titanium dioxide particles from orthopedic implants disrupt bone repair? September 16th, 2017

Arrowhead Hosts Investor & Analyst R&D Day to Introduce TRiM(TM) Platform and Lead RNAi-based Drug Candidates September 14th, 2017

Graphene based terahertz absorbers: Printable graphene inks enable ultrafast lasers in the terahertz range September 13th, 2017

Applications for the nanomedTAB are open until September 18th, 2017 September 13th, 2017

Announcements

Enhancing the sensing capabilities of diamonds with quantum properties: A simple method can give diamonds the special properties needed for quantum applications such as sensing magnetic fields September 24th, 2017

Quantum twisted Loong confirms the physical reality of wavefunctions September 23rd, 2017

Application of air-sensitive semiconductors in nanoelectronics: 2-D semiconductor gallium selenide in encapsulated nanoelectronic devices September 22nd, 2017

Researchers set time limit for ultrafast perovskite solar cells September 22nd, 2017

Nanobiotechnology

DNA triggers shape-shifting in hydrogels, opening a new way to make 'soft robots' September 21st, 2017

Do titanium dioxide particles from orthopedic implants disrupt bone repair? September 16th, 2017

Applications for the nanomedTAB are open until September 18th, 2017 September 13th, 2017

Magnetic cellular 'Legos' for the regenerative medicine of the future September 12th, 2017

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