In summer 2008, Dr. Nikhil Gupta, a materials scientist in the Mechanical and Aerospace Engineering Department at the Polytechnic Institute of NYU, contemplated applying to a private foundation or government agency to fund a study aimed at designing military body armor that would be more resistant to improvised explosive devices, such as the roadside bombs that have wounded soldiers serving in Iraq and Afghanistan.
Dr. Gupta knew that his best chance of obtaining funding was to propose a study that not only encompassed materials engineering but also examined the effects of high-energy explosives on bone and muscle tissue. In order to develop such a proposal, Dr. Gupta needed a collaborator with a background in bone and muscle tissue analysis as well as in biomaterials.
Dr. Dianne Rekow, Provost of the Polytechnic Institute of NYU and formerly Chair of NYUCD's Department of Basic Science and Craniofacial Biology, put Dr. Gupta in touch with Dr. Paulo G. Coelho, an Assistant Professor of Biomaterials & Biomimetics at NYUCD. Dr. Coelho's proficiency in the analysis of bone and muscle tissue complemented Dr. Gupta's skills in mechanical testing of materials using machines that he built in his laboratory to simulate the force of an explosion.
"I brought biomedical insight and bone mechanical behavior expertise to the table," says Dr. Coelho.
With their partnership in place, Drs. Gupta and Coelho worked collaboratively on a research proposal supported by an NYU-Polytechnic Seed Grant for Collaborative Research, as well as a supplement to a National Science Foundation grant awarded to Dr. Gupta.
"With the help of these grants, we have begun the process of engineering the ideal body armor," says Dr. Gupta. In the first phase of their study, the researchers found that high-energy forces, such as the shock waves emanating from an explosive device, can cause the protective foam liner in soldiers' helmets to compress into a stiff material that makes the impact of the explosion more pronounced and potentially more dangerous.
They also found that bone (femurs) exposed to such forces develop extensive fractures that can be too small to be detected by CT scans and other diagnostic technology. "This finding may explain why injuries in soldiers exposed to roadside bombs often go undetected for a long time," explains Dr. Coelho. "If not properly diagnosed and treated, these fractures may jeopardize immediate as well as long-term bone maintenance." Their findings were published in Materials Science and Engineering and in the Journal of Biomechanics.
Drs. Coelho and Gupta expect to secure funding from the US Army Research Laboratory to assess the impact of high-velocity forces on all major bones and muscles. They will use microcomputer tomography and scanning electron microscopes in the NYUCD biomaterials laboratory to detect and magnify microfractures by as much as 100,000 times.