Researchers have developed a patch that can monitor a patient’s condition and release blood-thinning medication to avoid dangerous blood clots.

Thrombosis, which can cause serious health problems including stroke and pulmonary embolism, is often treated with blood thinners. This requires patients regularly monitor themselves to ensure proper dosage of medication. The goal of the research team was to reduce errors in dosage which can lead to serious medical complications.

"Our goal was to generate a patch that can monitor a patient's blood and release additional drugs when necessary; effectively, a self-regulating system," says Zhen Gu, an associate professor in the joint biomedical engineering program at North Carolina State and North Carolina Universities.

Researchers tested a smart patch on mice. In the experiments, subjects were injected with large doses of thrombin, which would result in fatal blood clotting of the lungs if left untreated.

In the first experiment, mice were either left untreated, given a shot of Heparin, or given the smart patch. The mice were injected with thrombin 10 minutes later. Shortly after this injection, only the mice who did not receive treatment died.

In the second experiment, the thrombin was injected six hours after treatment. Fifteen minutes after the thrombin injection, all the mice with the HA-Heparin smart patch survived, but around 80 percent of the mice that received the Heparin shot had died.

"We're excited about the possibility of using a closed-loop, self-regulating smart patch to help treat a condition that affects thousands of people every year, while hopefully also driving down treatment costs," Gu says. "This paper represents a good first step, and we're now looking for funding to perform additional preclinical testing."

The study was published in the journal Advanced Materials.