C. Gourarie

A bioengineering team at the University of California San Diego (UCSD) has developed an injectable biosensor that detects alcohol use and wirelessly connects with a wearable device, allowing for continuous, long-term monitoring of alcohol use. The breakthrough could represent a new way to unobtrusively monitor alcohol intake to help in addiction recovery and more.“It’s really meant as a therapeutic device for treating alcoholism or treating other diseases where we know that alcohol is a major contributor towards the disease,” says Drew Hall, an electrical engineering professor at UCSD, who led the project (PDF) The chip is small enough (roughly 1 square millimeter) to be injected under the skin with a 16-gauge needle. It contains a sensor coated with alcohol oxidase, which produces a byproduct that can be electrochemically detected when it interacts with alcohol.“When we pay attention to behavior, it’s more likely to change,” says Carla Marienfeld, MD, an addiction psychiatrist who is working with the bioengineering team on the sensor.Existing tools for monitoring alcohol use include the breathalyzer and blood tests, which must be administered intermittently, with the right equipment, and only provide information on use over a limited period of time. Another limitation of current tools is that they primarily detect heavy alcohol use, whereas the sensor would detect any alcohol consumption.There have been several other developments in the area of alcohol monitoring, including noninvasive strategies like tattoos, patches, and wearable bracelets. In 2015, another team at UCSD’s Jacobs School of Engineering created a tattoo that detects levels of alcohol use and sends the information to a smartphone. Tattoos can be useful for intermittent monitoring but don’t provide the advantage of continuous tracking. And several companies have introduced bracelet sensors, including BACtrack , Milo, and Quantac, all of which won funding from the National Institute of Alcohol Abuse and Alcoholism.But the sensor is permanent, continuous, and reliable, says Marienfeld. “It’s actually in the body, so it’s not going to fall off,” she adds. “If you’re sweaty, it’s not going to rub off.”One key feature of the biosensor is that it is ultra low-power, consuming roughly one millionth of the power required to make a phone call via a smartphone. “If you make this low-enough power, you can harness the power of a wearable device,” says Hall, eliminating the need for a battery. The removal of the battery is what allows the sensor to be so small, and also gets rid of the most toxic components, allowing for the sensor to be injectable.The team has tested the sensor in a environment that mimics the human body, and it is getting ready to test it on animals. They are working with CARI Therapeutics and Marienfeld, in order to consider its application in substance abuse treatment. They are also working on sensors that will detect other substances, such as opiates.The sensor might also improve situations in which alcohol monitoring was mandated by the criminal justice system, or health or professional boards that require it of their employees.As an invasive procedure, it would be important for the participant to provide consent, says Marienfeld. However, while it may seem intrusive, it is a system that would benefit the participants, she says, by eliminating the need to check in to a physical location and other such inconveniences.Get the best insights in healthcare analytics directly to your inbox