The thought of eating a circuit board may not sound appetizing, but researchers are now pursuing medical advancements through an edible circuit board that generates electronic identifiers as it makes its way through the body. This innovation is inspiring pharmaceutical companies in both the field and in-patient care.

The edible circuit board is one of many new and unique techniques that include depositing a working agent to find the location of a disease. The dible circuit board is designed to venture through the body and monitor various health features.

A few of the leading companies advancing in this new way of delivering drugs include Boston Scientific Corp., Baxter International, Inc., Becton, Dickinson and Co. and Aequus Pharmaceuticals, according to USA News Group.

The “digital tattoo” creates monitored, electronic tags that can be used for a variety of information. These digital tattoos could potentially provide doctors with different diagnosis, control the rate drugs are released, and provide data collection points for health professionals.

The idea of ingestible electronic circuits is not a new concept, but thus far many of the proposed ideas have been bulky and expensive. They often use silicon-based electronics that responds to a pill the individual swallows.

Mario Carioni, a professor at the Polytechnic University of Milan, said the strategy of a “digital tattoo” is to allow the transferred electronic to perform multiple actions after it has been relocated onto food or a capsule. 

“Instead of directly printing the circuits on a capsule or on a fruit, we print the circuits on planar tattoo paper, and then we transfer the tattoo onto the target object,” said Carioni. “The tattoo releases an ultrathin ethyl cellulose substrate which nicely conforms to non-planar and also corrugated surfaces, assuming a 3D texture.”

Once printed onto a thin, film of ethyl cellulose, the digital tattoo is then stuck to a paper with water-soluble starch. The tattoo soaks in water and sticks to the skin of a fruit or capsule until the starch dissolves. Once the paper is peeled off, it leaves a small design on the “skin.”  

The ethyl cellulose that the tattoos release is edible and there are no chemicals released during the process. Carioni said patients should respond well since the patient’s skin would not actually be “tattooed.”

“The edible circuits in our vision will completely disappear in the edible item, and therefore, this should drastically reduce a negative response from patients,” said Carioni.

In order to test the idea of temporary tattoos, the researchers used an electric circuit printer and printed circuits made of silver and four semiconductor polymers on tattoo paper. They transferred these to drug capsules, strawberries and glass microscope slides.

The semiconductors are still in the testing stage of guaranteeing edibility. Carioni said although some are biocompatible, they still performed preliminary cytotoxicity tests with cell lines in the upper and lower part of the intestine, which is a first promising test to guarantee edibility.

Similar research happening at Proteus Digital in the U.S.  has produced pills with a silicon chip. Once ingested, the pill transmits a signal to a patch attached to the body. Edible electronics could mitigate the silicon chip and replace it with an edible element, Carioni said.

The purpose of the transferred electronic has potential to control release, sense medications and monitor drugs. It is opening new perspectives towards smart-tailored medications and food tracking and monitoring.

“Our dream is to develop pills with edible circuits and sensors capable of monitoring the GI tract in search for dangerous bacteria…” said Carioni. “This would allow a real time monitoring, for example patients in the hospital, where such an issue is becoming more and more critical. However, our research is only a very small step to opening the path towards edible circuits.” 

Feature Photo Credit: Flexible, edible electronic circuits on a pharmaceutical capsule represent an emerging generation of edible circuits being developed to monitor functions as they travel through the body. Credit: Physics World.