UCSD Students Develop Chip Implant to Monitor Blood Alcohol Content

Students at UC San Diego have created a tiny biosensor that can wirelessly monitor the blood alcohol levels of its user. The project’s goal is to develop an unobtrusive way to continuously monitor alcohol and drug levels of patients in substance abuse treatment programs.

The biosensor chip is injected into the user’s skin and is powered wirelessly by an external smartwatch or patch. Preliminary studies have demonstrated that the lifetime of the device is greater than 30 days, although research is still ongoing.

UCSD electrical engineering professor Drew Hall who served as the faculty advisor for the project, explains that the sensor works by monitoring the levels of hydrogen peroxide present in the body.

The chip works similarly to a glucometer,” Hall described. “A chemical reaction takes place on the surface of the sensor that generates a byproduct (hydrogen peroxide in both cases) that is detected by the sensor. Here, we use alcohol oxidase which catalyzes alcohol and also produces hydrogen peroxide.”

Recent advancements in continuous glucose monitor technology have resulted in lifespans of over two years.

“Since our BioMote is functionally equivalent, I’m optimistic that we will be able to improve the lifetime dramatically over time,” Hall told the UCSD Guardian.

Pending additional research, the team currently plans to send the information collected by the sensor to the user’s smartphone, which can then be sent to healthcare professionals. The research is being conducted in collaboration with CARI Therapeutics, a biotechnology startup incubating at Qualcomm Institute that specializes in the detection, monitoring, and treatment of drug and alcohol misuse.

Along with CARI Therapeutics, the team is now applying for a second-phase testing grant from the National Science Foundation to test the device in animals next year.

Hall explains that this technology can also be used to monitor levels of other substances in the blood.

“By changing the surface chemistry, we can change what biomolecule we are observing,” Hall wrote in an email to the Guardian. “For example, to monitor glucose, one immobilizes glucose oxidase, an enzyme that catalyzes glucose and generates a hydrogen peroxide by-product. We have a grant from the National Institutes of Health to develop assays for opioids — morphine, fentanyl, etc. — and other drugs of abuse.”

As the research is still in progress, the team has yet to discover all of the failure mechanisms of the technology. Along with in-vitro testing, the team hopes to proceed to animal testing and small-scale human trials. In the meantime, they have also filed a patent for the technology.