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 Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

nachricht How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>