With a $1.6M grant from the U.S. Office of Naval Research (ONR), UC
San Diego NanoEngineering professor Joseph Wang will lead a project to create
a "field hospital on a chip" that soldiers can wear on the battlefield.
The automated sense-and-treat system being developed by UC San Diego NanoEngineering professor Joseph Wang and colleagues will continuously monitor a soldier’s sweat, tears or blood for biomarkers that signal common battlefield injuries such as trauma, shock, brain injury or fatigue. Once the system detects a battlefield injury, it will automatically administer the proper medication, thus beginning the treatment well before the soldier has reached a field hospital. Credit: UC San Diego Jacobs School of Engineering
The automated sense-and-treat system will continuously monitor a soldier's
sweat, tears or blood for biomarkers that signal common battlefield injuries
such as trauma, shock, brain injury or fatigue. Once the system detects a battlefield
injury, it will automatically administer the proper medication, thus beginning
the treatment well before the soldier has reached a field hospital.
"Since the majority of battlefield deaths occur within the first 30 minutes
after injury, rapid diagnosis and treatment are crucial for enhancing the survival
rate of injured soldiers," said Joseph Wang, a NanoEngineering professor
at the Jacobs School of Engineering at UC San Diego and the Primary Investigator
on the project.
To realize their "field hospital on a chip" idea, the engineers will
need to build a minimally invasive system that monitors multiple biomarkers
simultaneously and uses the system's "smarts" to process all this
biomarker information and tease out accurate, automated diagnoses. These diagnoses
would immediately trigger drug delivery or other medical intervention.
"Today's insulin and glucose management systems for patients with diabetes
don't include smart sensors capable of performing complex logic operations,"
said Wang, who helped to develop the first noninvasive system for monitoring
glucose from a patient's sweat. "We are working on a system that will be
different. It will monitor biomarkers and make decisions about the type of injury
a person has sustained and then begin treating that person accordingly,"
said Wang.
"Developing an effective interface between complex physiological processes
and implantable devices could have a broader biomedical impact, providing autonomous,
individual, 'on-demand' medical care, which is the goal of the new field of
personalized medicine," said Wang.
To reach this level of automated diagnostic dexterity, the researchers plan
to build upon "enzyme logic" breakthroughs recently demonstrated by
Evgeny Katz, a Co-PI on the grant and the Milton Kerker Chaired professor of
Chemistry and Biomolecular Science at Clarkson University.
Katz and colleagues demonstrated recently that enzymes can not only measure
biomarkers, but also provide the logic necessary to make a limited set of diagnoses
based on multiple biological variables.
One of the many challenges now facing Wang and his team, however, is to get
the enzyme logic system to reliably work on sensing electrodes that humans can
wear. Thus far, enzyme logic operations have only been demonstrated in solution.
From Biomarkers to 1s and 0s and Treatment
Lactate, oxygen, norepinephrine and glucose are examples as the kinds of injury
biomarkers that will serve as biological input signals for their prototype logic
system. Electrodes containing a combination of enzymes will serve as sensors
and provide the logic necessary to convert the biomarkers to products which
may then be picked up by another enzyme on the electrode for further logic operations.
The electrodes will also act as transducers that produce strings of 1s and 0s
that will activate smart materials that release medication based on predetermined
treatment plans.
"We just want the ones and zeros. The pattern of ones and zeros will reveal
the type of injury and automatically trigger the proper treatment," said
Wang.
For example, if an injured soldier were to enter a state of shock, enzymes
on the electrode would sense rising levels of the biomarkers lactate, glucose
and norepinephrine. In turn, the concentrations of products generated by the
enzymes would change—higher hydrogen peroxide, lower norepi-quinone, higher
NADH and lower NAD+. This will cause the built-in logic structure to output
the signal "1,0,1,0" which points to shock and will trigger a pre-determined
treatment response.
"This is biocomputing in action," said Wang.
"We are just at the beginning of this project. During the first two years,
our primary focus will be on the sensor systems. Integrating enzyme logic onto
electrodes that can read biomarker inputs from the body will be one of our first
major challenges," said Wang.
At the end of the four-year project, the researchers expect to have a working
prototype that can detect different combinations of injury biomarkers thanks
to the enzyme logic. At the same time, the researchers will also be working
on signal-responsive membranes that can release drugs, as well as the electrical
or optoelectronic systems that allow the sensors to communicate with the drug
delivery system.
"We really hope that our enzyme-logic sense-and-treat system will revolutionize
the monitoring and treatment of injured soldiers and lead to dramatic improvements
in their survival rate," said Wang.