Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Special Gold Nanoparticles Show Promise for “Cooking” Cancer Cells

24.03.2009
Researchers are describing a long-awaited advance toward applying the marvels of nanotechnology in the battle against cancer.

They have developed the first hollow gold nanospheres — smaller than the finest flecks of dust — that search out and “cook” cancer cells. The cancer-destroying nanospheres show particular promise as a minimally invasive future treatment for malignant melanoma, the most serious form of skin cancer, the researchers say. Melanoma now causes more than 8,000 deaths annually in the United States alone and is on the increase globally.

The topic of a report presented here today at the American Chemical Society’s 237th National Meeting, the hollow gold nanospheres are equipped with a special “peptide.” That protein fragment draws the nanospheres directly to melanoma cells, while avoiding healthy skin cells. After collecting inside the cancer, the nanospheres heat up when exposed to near-infrared light, which penetrates deeply through the surface of the skin. In recent studies in mice, the hollow gold nanospheres did eight times more damage to skin tumors than the same nanospheres without the targeting peptides, the researchers say.

“This technique is very promising and exciting,” explains study co-author Jin Zhang, Ph.D., a professor of chemistry and biochemistry at the University of California in Santa Cruz. “It’s basically like putting a cancer cell in hot water and boiling it to death. The more heat the metal nanospheres generate, the better.”

This form of cancer therapy is actually a variation of photothermal ablation, also known as photoablation therapy (PAT), a technique in which doctors use light to burn tumors. Since the technique can destroy healthy skin cells, doctors must carefully control the duration and intensity of treatment.

Researchers now know that PATs can be greatly enhanced by applying a light absorbing material, such as metal nanoparticles, to the tumor. Although researchers have developed various types of metal nanoparticles to help improve this technique, many materials show poor penetration into cancer cells and limited heat carrying-capacities. These particles include solid gold nanoparticles and nanorods that lack the desired combination of spherical shape and strong near-infrared light absorption for effective PAT, scientists say.

To develop more effective cancer-burning materials, Zhang and colleagues focused on hollow gold nanospheres — each about 1/50,000th the width of a single human hair. Previous studies by others suggest that gold “nanoshells” have the potential for strong near-infrared light absorption. However, scientists have been largely unable to produce them successfully in the lab, Zhang notes.

After years of research toward this goal, Zhang announced in 2006 that he had finally developed a nanoshell or hollow nanosphere with the “right stuff” for cancer therapy: Gold spheres with an optimal light absorption capacity in the near-infrared region, small size, and spherical shape, perfect for penetrating cancer cells and burning them up.

“Previously developed nanostructures such as nanorods were like chopsticks on the nanoscale,” Zhang says. “They can go through the cell membrane, but only at certain angles. Our spheres allow a smoother, more efficient flow through the membranes.”

The gold nanoshells, which are nearly perfect spheres, range in size from 30 to 50 nanometers — thousands of times smaller than the width of a human hair. The shells are also much smaller than other nanoparticles previously designed for photoablation therapy, he says. Another advantages is that gold is also safer and has fewer side effects in the body than other metal nanoparticles, Zhang notes.

In collaboration with Chun Li, Ph.D., a professor at the University of Texas M.D. Anderson Cancer Center in Houston, Zhang and his associates equipped the nanospheres with a peptide to a protein receptor that is abundant in melanoma cells, giving the nanospheres the ability to target and destroy skin cancer. In tests using mice, the resulting nanospheres were found to be significantly more effective than solid gold nanoparticles due to much stronger near infrared-light absorption of the hollow nanospheres, the researchers say.

The next step is to try the nanospheres in humans, Zhang says. This requires extensive preclinical toxicity studies. The mice study is the first step, and there is a long way to go before it can be put into clinical practice, Li says.

The U.S. Department of Defense and the National Science Foundation funded the research in Zhang’s lab while the National Institutes of Health funded the work in Dr. Li’s lab.

The American Chemical Society is a nonprofit organization chartered by the U.S. Congress. With more than 154,000 members, ACS is the world’s largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.

Michael Bernstein | Newswise Science News
Further information:
http://www.acs.org

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>