Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nanoengineers mine tiny diamonds for drug delivery

15.10.2007
Northwestern University researchers have shown that nanodiamonds -- much like the carbon structure as that of a sparkling 14 karat diamond but on a much smaller scale -- are very effective at delivering chemotherapy drugs to cells without the negative effects associated with current drug delivery agents.

Their study, published online by the journal Nano Letters, is the first to demonstrate the use of nanodiamonds, a new class of nanomaterials, in biomedicine. In addition to delivering cancer drugs, the model could be used for other applications, such as fighting tuberculosis or viral infections, say the researchers.

Nanodiamonds promise to play a significant role in improving cancer treatment by limiting uncontrolled exposure of toxic drugs to the body. The research team reports that aggregated clusters of nanodiamonds were shown to be ideal for carrying a chemotherapy drug and shielding it from normal cells so as not to kill them, releasing the drug slowly only after it reached its cellular target.

Another advantage of the material, confirmed by a series of genetic studies also reported in the paper, is that nanodiamonds do not cause cell inflammation once the drug has been released and only bare diamonds are left. Materials currently used for drug delivery can cause inflammation, a serious complication that can predispose a patient to cancer, block the activity of cancer drugs and even promote tumor growth.

“There are a lot of materials that can deliver drugs well, but we need to look at what happens after drug delivery,” said Dean Ho, assistant professor of biomedical engineering and mechanical engineering at Northwestern’s McCormick School of Engineering and Applied Science, who led the research. “How do cells react to an artificial material left in the body? Nanodiamonds are highly ordered structures, which cells like. If they didn’t, cells would become inflamed. From a patient’s perspective, this is very important. And that’s why clinicians are interested in our work.”

“Novel drug delivery systems, such as the one being developed by Dean and his team, hold great promise in cancer therapeutics,” said Steven Rosen, M.D., director of the Robert H. Lurie Comprehensive Cancer Center of Northwestern University and Genevieve E. Teuton Professor of Medicine at Northwestern’s Feinberg School of Medicine. “We anticipate they will allow for more sophisticated means of targeting cancer cells while sparing healthy cells from a drug’s toxicity.”

To make the material effective, Ho and his colleagues manipulated single nanodiamonds, each only two nanometers in diameter, to form aggregated clusters of nanodiamonds, ranging from 50 to 100 nanometers in diameter. The drug, loaded onto the surface of the individual diamonds, is not active when the nanodiamonds are aggregated; it only becomes active when the cluster reaches its target, breaks apart and slowly releases the drug. (With a diameter of two to eight nanometers, hundreds of thousands of diamonds could fit onto the head of a pin.)

“The nanodiamond cluster provides a powerful release in a localized place -- an effective but less toxic delivery method,” said co-author Eric Pierstorff, a molecular biologist and post-doctoral fellow in Ho’s research group. Because of the large amount of available surface area, the clusters can carry a large amount of drug, nearly five times the amount of drug carried by conventional materials.

Liposomes and polymersomes, both spherical nanoparticles, currently are used for drug delivery. While effective, they are essentially hollow spheres loaded with an active drug ready to kill any cells, even healthy cells that are encountered as they travel to their target. Liposomes and polymersomes also are very large, about 100 times the size of nanodiamonds -- SUVs compared to the nimble nanodiamond clusters that can circulate throughout the body and penetrate cell membranes more easily.

Unlike many of the emerging nanoparticles, nanodiamonds are soluble in water, making them clinically important. “Five years ago while working in Japan, I first encountered nanodiamonds and saw it was a very soluble material,” said materials scientist Houjin Huang, lead author of the paper and also a post-doctoral fellow in Ho’s group. “I thought nanodiamonds might be useful in electronics, but I didn’t find any applications. Then I moved to Northwestern to join Dean and his team because they are capable of engineering a broad range of devices and materials that interface well with biological tissue. Here I’ve focused on using nanodiamonds for biomedical applications, where we’ve found success.

“Nanodiamonds are very special,” said Huang. “They are extremely stable, and you can do a lot of chemistry on the surface, to further functionalize them for targeting purposes. In addition to functionality, they also offer safety -- the first priority to consider for clinical purposes. It’s very rare to have a nanomaterial that offers both.”

“It’s about optimizing the advantages of a material,” said Ho, a member of the Lurie Cancer Center. “Our team was the first to forge this area -- applying nanodiamonds to drug delivery. We’ve talked to a lot of clinicians and described nanodiamonds and what they can do. I ask, ‘Is that useful to you?’ They reply, ‘Yes, by all means.’”

For their study, Ho and his team used living murine macrophage cells, human colorectal carcinoma cells and doxorubicin hydrochloride, a widely used chemotherapy drug. The drug was successfully loaded onto the nanodiamond clusters, which efficiently ferried the drug inside the cells. Once inside, the clusters broke up and slowly released the drug.

In the genetic studies, the researchers exposed cells to the bare nanodiamonds (no drug was present) and analyzed three genes associated with inflammation and one gene for apoptosis, or cell death, to see how the cells reacted to the foreign material. Looking into the circuitry of the cell, they found no toxicity or inflammation long term and a lack of cell death. In fact, the cells grew well in the presence of the nanodiamond material.

Megan Fellman | EurekAlert!
Further information:
http://www.northwestern.edu

More articles from Studies and Analyses:

nachricht Multi-year study finds 'hotspots' of ammonia over world's major agricultural areas
17.03.2017 | University of Maryland

nachricht Diabetes Drug May Improve Bone Fat-induced Defects of Fracture Healing
17.03.2017 | Deutsches Institut für Ernährungsforschung Potsdam-Rehbrücke

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>