Advances in the skin trade

Skin Like Armor

By Gale Morrison, Associate Editor

MGI's manufacturing process can be described as micron-scale rapid prototyping, engineering expertise that has been evolving for about 15 years.

The company is developing manufacturing approaches to create porous scaffolds that mimic the microstructure of living materials, and lately has turned its skill to a research project on biofiltration funded by the Defense Advanced Research Projects Agency.

DARPA went through a metamorphosis during the 1990s as the Cold War ended and defense spending was reevaluated. Founded in 1958 when the technology of Sputnik put the fear of Russian technological prowess into America, the agency seeded all manner of defense and aerospace technologies over the past four decades.

In the 1970s and 1980s, DARPA millions could be won by corporations developing products relatively close to market (this included ARPAnet, ancestor of the Internet, and many computer chip innovations). By the middle of this decade, DARPA had to return to its roots—ensuring the most advanced defense technologies, such as high-end missile avoidance components, and keeping the United States up on technological change so the country would not fall behind some future adversary. A project like Molecular Geodesics' falls into this league.

In April 1997, MGI was awarded a two-year $6.4 million contract from DARPA in the area of "biomimetic materials for pathogen neutralization."

Under the contract, MGI will develop a biological detoxification capability in the form of synthetic biomimetic materials that will capture and neutralize biological agents before they enter the body.

These materials will be applied to the development of protective masks, cooling vents for conventional battle dress overgarments, and artificial bioskins (the battle dress of the future) in order to provide generic countermeasures to biological warfare agents.

The major advantage of the MGI approach over other forms of defensive shielding is that these new porous materials will incorporate chemical, enzymatic, and physical features to destroy toxic agents.

The protective fabrics and filtration devices will be lightweight, easily worn, and interfere only minimally with the wearer's mobility, yet effectively resist inadvertent tearing or puncture.

The porosity and hydrogel-like features of the biomimetic material will allow it to soak up pathogens and toxins like a hydrated sponge. Due to the incorporation of biologically active chemicals and enzymes within the hydrogel-like layer, toxic agents will be neutralized and inactivated once they enter the interstices of the material.

These materials also will incorporate optical fibers within their weave to deliver local ultraviolet radiation for generic sterilization of pathogens and for decontamination of garments, treatments that likely will be necessary for extended use in the field.

MGI is coating these porous scaffolds with a synthetic "protoplasm" composed of bioactive hydrogels, which exhibit a range of biochemical processes at levels of efficiency similar to that in living cells and tissues.

Polymer synthesis and hydrogel fabrication capabilities have been developed through a subcontract with Tony Mikos, a professor in the Department of Bioengineering at Rice University in Houston.

The company needed to bring in Mikos at this point, according to A.J. Meuse, MGI's chief operating officer. "Hydrogel development and formulation is known to us, but he does it better than anyone else," Meuse said. "We share researchers and technology."

Additional programs in development at MGI include heat dissipators for the computer industry, and novel replacements for foams, honeycombs, and impact-resistant building materials.

In addition, MGI has a proprietary self-assembly-based manufacturing technique, which can be used to create cylindrical metal microdevices, such as stents, for the biomedical market.

For its work in rapid prototyping, the company has a corporate alliance with Laser Fare Inc. of Warwick, R.I. Laser Fare's technology is overseen by two veterans of stereolithography, Terry Feeley and Paul Jacobs.