A team at the University of California San Diego has received a grant from the U.S. Office of Naval Research to develop a “hospital-on-a-chip” system that will, in the far off distant future, have a wearable device to sense the body’s biochemical changes, which will then be linked through a computer controller to a unit that can administer medicine based on the sensor’s findings. Hopefully one day this technology will provide initial treatment to soldiers wounded in the field, and may very well find itself in commercial applications such automated systems for diabetics.
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.
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.
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.