Nanohealing Material Heads to Market

Monday, May 12, 2008

A startup is planning human trials for a nanostructured material that quickly stops bleeding.

By Kevin Bullis

Blood stopper: The clear fluid in this dish transforms into a gel in the presence of blood; such a gel can stops bleeding almost instantly.
Credit: Asia Kepka

A startup based in Cambridge, MA, says that it plans to soon begin clinical trials of a nanostructured material that stops bleeding almost instantly. A startup called Arch Therapeutics has licensed the technology from MIT and is developing manufacturing processes for making it in large amounts.

The new material can be poured over a site and will stop the bleeding almost at once.

The first application, pending Food and Drug Administration approval, will be for use during surgery to quickly stop bleeding and even prevent it in the first place. Floyd Loop, currently an advisor to Arch Therapeutics, and formerly a cardiovascular surgeon and the head of Cleveland Clinic, says that it could be useful in a wide variety of surgeries, including brain, heart, and prostate. For example, he says that when large tumors are removed, "there's a lot of diffuse bleeding around the site, and you have to spend a lot of time with sponges and cautery stopping it."

Loops says that in addition to saving time, which can improve the outcome of a surgery, the material could decrease the need for transfusions and reoperations to control bleeding. What's more, it could reduce the risk of infection. It could be used, for instance, to prevent leakage after bowel-repair surgery. "I've never seen anything like it," Loop says.

Eventually, the material could be used by first responders to stop bleeding at accident sites and on the battlefield. It has a long shelf life, which makes it attractive for use in first-aid kits. It's also easily broken down by the body, so it doesn't have to be removed, unlike other agents for stopping blood flow. However, Loop cautions that further tests are needed to confirm that the material will work in nonsurgical applications.

The material, a synthetic peptide, was discovered at MIT in the early 1990s. But it wasn't until a few years ago that its potential for stopping bleeding was discovered. Rutledge Ellis-Behnke, a researcher at MIT's Department of Brain and Cognitive Sciences, was exploring its potential use to promote the healing of brain injuries. When he applied a liquid containing the synthetic peptides to a wound site in animal experiments, bleeding in the area stopped within a few seconds. Arch Therapeutics was founded in mid-2006 to develop the material for commercial use. The company made its first public appearance late last month when it announced a finalized licensing agreement for the new technology.

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Peptides provide fatal blow for cancer cells

21 April 2008

Peptide nanostructures that punch holes in cancer cells are 'the first step towards efficient nanochemotherapeutics,' say chemists in Canada.

Normand Voyer and colleagues at the University of Laval in Québec have designed a series of modified peptide nanostructures that can puncture cancer cell membranes, leading to the cells' death.

"In the past decade, cancer cell resistance to chemotherapeutic agents has led to increased cancer deaths"

The team explains that in the past decade, cancer cell resistance to chemotherapeutic agents has led to increased cancer deaths. 'We believe that nanochemotherapeutics can overcome this problem due to the particular properties of nanometre-sized compounds,' says Voyer.

Basing their structures on a membrane-disrupting peptide they had made previously, the researchers engineered analogues that would be selective for cancer cells. The engineered peptides are inactive until they reach cancer cell surfaces where they convert into an active cell membrane disruption agent. Since the enzyme that activates the peptides is over-expressed in prostate cancer cells, normal cells do not activate the peptide to the same extent, leading to the peptides' selectivity.

When cancer cells (left) are treated with peptide nanostructures their cell membranes are destroyed (right)

Vincent Rotello, an expert in the supramolecular chemistry of biological and materials systems at the University of Massachusetts, Amherst, US, is enthusiastic about the findings. 'While enzymatic activation has been used before for therapeutics,' he says, 'this peptide-based scaffold has great promise due to the modular nature of its construction.' This is because the amino acid building blocks used to assemble the peptides can be readily varied, which provides 'incredible control over the structure and dynamics of the eventual therapeutics,' Rotello adds.

Voyer explains that the work 'illustrates chemists' abilities to design novel nanometre-sized molecular architectures from scratch to address highly challenging problems.' Future efforts will be geared towards 'determining the mechanism of action of this new class of antitumour agents,' he adds.

Kathleen Too

Link to journal article: Nanoscale tools to selectively destroy cancer cells

Pierre-Luc Boudreault, Mathieu Arseneault, François Otis and Normand Voyer, Chem. Commun., 2008, 2118
DOI: 10.1039/b800528a

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