Nanotechnology Now





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > MIT: Targeting tumors using tiny gold particles --Gold nanorods could detect, treat cancer

Photo / Sangeeta Bhatia Laboratory; MIT
MIT researchers developed these gold nanorods that absorb energy from near-infrared light and emit it as heat, destroying cancer cells
Photo / Sangeeta Bhatia Laboratory; MIT
MIT researchers developed these gold nanorods that absorb energy from near-infrared light and emit it as heat, destroying cancer cells

Abstract:
It has long been known that heat is an effective weapon against tumor cells. However, it's difficult to heat patients' tumors without damaging nearby tissues.

Now, MIT researchers have developed tiny gold particles that can home in on tumors, and then, by absorbing energy from near-infrared light and emitting it as heat, destroy tumors with minimal side effects.

MIT: Targeting tumors using tiny gold particles --Gold nanorods could detect, treat cancer

Cambridge, MA | Posted on May 4th, 2009

Such particles, known as gold nanorods, could diagnose as well as treat tumors, says MIT graduate student Geoffrey von Maltzahn, who developed the tumor-homing particles with Sangeeta Bhatia, professor in the Harvard-MIT Division of Health Sciences and Technology (HST) and in the Department of Electrical Engineering and Computer Science, a member of the David H. Koch Institute for Integrative Cancer Research at MIT and a Howard Hughes Medical Institute Investigator.

Von Maltzahn and Bhatia describe their gold nanorods in two papers recently published in Cancer Research and Advanced Materials. In March, von Maltzahn won the Lemelson-MIT Student Prize, in part for his work with the nanorods.

Cancer affects about seven million people worldwide, and that number is projected to grow to 15 million by 2020. Most of those patients are treated with chemotherapy and/or radiation, which are often effective but can have debilitating side effects because it's difficult to target tumor tissue.

With chemotherapy treatment, 99 percent of drugs administered typically don't reach the tumor, said von Maltzahn. In contrast, the gold nanorods can specifically focus heat on tumors.

"This class of particles provides the most efficient method of specifically depositing energy in tumors," he said.

Wiping out tumors

Gold nanoparticles can absorb different frequencies of light, depending on their shape. Rod-shaped particles, such as those used by von Maltzahn and Bhatia, absorb light at near-infrared frequency; this light heats the rods but passes harmlessly through human tissue.

In a study reported in the team's Cancer Research paper, tumors in mice that received an intravenous injection of nanorods plus near-infrared laser treatment disappeared within 15 days. Those mice survived for three months with no evidence of reoccurrence, until the end of the study, while mice that received no treatment or only the nanorods or laser, did not.

Once the nanorods are injected, they disperse uniformly throughout the bloodstream. Bhatia's team developed a polymer coating for the particles that allows them to survive in the bloodstream longer than any other gold nanoparticles (the half-life is greater than 17 hours).

In designing the particles, the researchers took advantage of the fact that blood vessels located near tumors have tiny pores just large enough for the nanorods to enter. Nanorods accumulate in the tumors, and within three days, the liver and spleen clear any that don't reach the tumor.

During a single exposure to a near-infrared laser, the nanorods heat up to 70 degree Celsius, hot enough to kill tumor cells. Additionally, heating them to a lower temperature weakens tumor cells enough to enhance the effectiveness of existing chemotherapy treatments, raising the possibility of using the nanorods as a supplement to those treatments.

The nanorods could also be used to kill tumor cells left behind after surgery. The nanorods can be more than 1,000 times more precise than a surgeon's scalpel, says von Maltzahn, so they could potentially remove residual cells the surgeon can't get.

Finding tumors

The nanorods' homing abilities also make them a promising tool for diagnosing tumors. After the particles are injected, they can be imaged using a technique known as Raman scattering. Any tissue that lights up, other than the liver or spleen, could harbor an invasive tumor.

In the Advanced Materials paper, the researchers showed they could enhance the nanorods' imaging abilities by adding molecules that absorb near-infrared light to their surface. Because of this surface-enhanced Raman scattering, very low concentrations of nanorods — to only a few parts per trillion in water — can be detected.

Another advantage of the nanorods is that by coating them with different types of light-scattering molecules, they can be designed to simultaneously gather multiple types of information — not only whether there is a tumor, but whether it is at risk of invading other tissues, whether it's a primary or secondary tumor, or where it originated.

Bhatia and von Maltzahn are looking into commercializing the technology. Before the gold nanorods can be used in humans, they must undergo clinical trials and be approved by the FDA, which von Maltzahn says will be a multi-year process.

Other authors of the Advanced Materials paper are Andrea Centrone, postdoctoral associate in chemical engineering; Renuka Ramanathan, undergraduate in biological engineering; Alan Hatton, the Ralph Landau Professor of Chemical Engineering; and Michael Sailor and Ji-Ho Park of the University of California at San Diego.

Park and Sailor are also authors of the Cancer Research paper, along with Amit Agrawal, former postdoctoral associate in HST; and Nanda Kishor Bandaru and Sarit Das of the Indian Institute of Technology Madras.

The research was funded by the National Institutes of Health, the Whitaker Foundation and the National Science Foundation. Nanopartz Inc. supplied gold nanoparticles, gold nanowires and the precursor gold nanorods used in this work.

Written by Anne Trafton, MIT News Office

####

About MIT
The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the 21st century.

For more information, please click here

Contacts:
Elizabeth A. Thomson
MIT News Office

T: 617-258-5402

Copyright © MIT

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

Discovery of nanotubes offers new clues about cell-to-cell communication July 2nd, 2015

Nanospiked bacteria are the brightest hard X-ray emitters July 2nd, 2015

Engineering the world’s smallest nanocrystal July 2nd, 2015

Producing spin-entangled electrons July 2nd, 2015

Govt.-Legislation/Regulation/Funding/Policy

New technology using silver may hold key to electronics advances July 2nd, 2015

NIST Group Maps Distribution of Carbon Nanotubes in Composite Materials July 2nd, 2015

NIST ‘How-To’ Website Documents Procedures for Nano-EHS Research and Testing July 1st, 2015

Ultra-stable JILA microscopy technique tracks tiny objects for hours July 1st, 2015

Academic/Education

Oxford Instruments’ TritonXL Cryofree dilution refrigerator selected for the Oxford NQIT Quantum Technology Hub project June 30th, 2015

Rice University boots up powerful microscopes: New electron microscopes will capture images at subnanometer resolution June 29th, 2015

Six top Catalan research centres constitute ‘The Barcelona Institute of Science and Technology’ to pursue a joint scientific endeavour June 27th, 2015

Lancaster University revolutionary quantum technology research receives funding boost June 22nd, 2015

Nanomedicine

Iranian Scientists Find Simple, Economic Method to Synthesize Antibacterial Nanoparticles July 2nd, 2015

Leti Announces Launch of First European Nanomedicine Characterisation Laboratory: Project Combines Expertise of 9 Partners in 8 Countries to Foster Nanomedicine Innovation and Facilitate Regulatory Approval July 1st, 2015

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

Chitosan coated, chemotherapy packed nanoparticles may target cancer stem cells June 30th, 2015

Discoveries

Freezing single atoms to absolute zero with microwaves brings quantum technology closer: Atoms frozen to absolute zero using microwaves July 2nd, 2015

New technology using silver may hold key to electronics advances July 2nd, 2015

Discovery of nanotubes offers new clues about cell-to-cell communication July 2nd, 2015

Nanospiked bacteria are the brightest hard X-ray emitters July 2nd, 2015

Announcements

Nanospiked bacteria are the brightest hard X-ray emitters July 2nd, 2015

Engineering the world’s smallest nanocrystal July 2nd, 2015

Producing spin-entangled electrons July 2nd, 2015

NIST Group Maps Distribution of Carbon Nanotubes in Composite Materials July 2nd, 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