The highlight of the recent Association of Health Care Journalists (AHCJ) annual meeting in Philadelphia (Health Journalism 2011) for me was the presentation by Kacy Cullen from the Center for Brain Injury and Repair in the Department of Neurosurgery at the University of Pennsylvania.
Dr Cullen presented his research on blast-induced traumatic brain injury (bTBI) and the development of a nanomaterial containing photonic crystals that change color upon exposure to blast pressure.
In the same way that a radiation dosimeter badge records exposure to cumulative radiation for a hospital worker, so a helmet-mounted color badge would change color based on a soldier’s exposure to blast pressure; a common occurrence with improvised explosive devices (IED).
In a paper published in NeuroImage, Cullen and colleagues describe in detail a blast-injury dosimeter (BID) made from photosensitive polymers that is like a colored sticker. This nanomaterial contains microscopic, diamond-like photonic crystals, whose ability to refract light is damaged in a precise way by the pressure from explosive blasts.
The result is a change in color that is related to the degree of pressure and blast intensity. What’s more because the photonic crystals are structurally damaged by the blast, further exposure leads to more widespread microstructural alterations and a further change in color. In essence, the crystals have a memory for cumulative blast exposure.
Why is this important?
Many soldiers are exposed to blasts, but show no overt symptoms of traumatic brain injury. Research has shown that repeated hits to the helmet of a football player can lead to brain injury without the obvious signs of a concussion. Traumatic brain injury as a result of repeated exposure to blasts may also lead to mild cognitive impairment and the possibility of increased risk for dementia, Alzheimer’s disease later in life. This has been seen in NFL players.
The research by Cullen and colleagues is still in the early stages of development. In their paper they acknowledge some of the next steps such as calibrating the color changes to levels of blast exposure, and correlating these with traumatic brain injury. Any blast injury dosimeter will also need to be field tested.
However, this work is promising and an example of how nanotechnology may impact the detection and diagnosis of those soldiers at risk of traumatic brain injury.
War related scientific research often leads to civilian applications. In the future, I could see nanotechnology stickers that change color with cumulative impact on the helmets of NFL, college or high school football players.
You can read more about this innovative research on how color changing photonic crystals detect blast exposure in the journal NeuroImage.
Update June 30, 2011
If you are interested in the exciting and innovative research being undertaken by Kacy Cullen and his team, there is now a website for The Cullen Laboratory and their work on Neural Engineering in Neurotrauma.
Cullen, D., Xu, Y., Reneer, D., Browne, K., Geddes, J., Yang, S., & Smith, D. (2011). Color changing photonic crystals detect blast exposure NeuroImage, 54 DOI: 10.1016/j.neuroimage.2010.10.076