Paper patch could help diabetics monitor sugar level

Researchers have developed a new paper-based sensor patch that could allow diabetics to effectively measure glucose levels during exercise. In a paper published in the journal Micromachines, the researchers demonstrated a self-powered, wearable and disposable patch that allows for non-invasive monitoring of glucose in human sweat.

This wearable, single-use biosensor integrates a vertically stacked, paper-based glucose/oxygen enzymatic fuel cell into a standard Band-Aid adhesive patch.

"The paper-based device attaches directly to skin, wicks sweat to a reservoir where chemical energy is converted to electrical energy, and monitors glucose without external power and sophisticated readout instruments," said Seokheun Choi, Assistant Professor at Binghamton University, State University of New York.

Today's most widespread methods for glucose self-testing involve monitoring glucose levels in blood. Conventional measurements, however, are not suitable for preventing hypoglycemia (low blood glucose) during exercise, Choi said.

This is because the underlying process relies on invasive and inconvenient blood sampling, causing the possibility of sample contamination and skin irritation with sweat containing various electrolytes and proteins, Choi said.

Moreover, the method needs patients to carry many accessories during physical activity, including lancets, alcohol swabs and a relatively large glucometer.

"The technique requires a sophisticated electrochemical sensing technique and sufficient electrical energy, which makes the technique difficult to be fully integrated in a compact and portable fashion," Choi added.

On the other hand, sweat-based glucose sensing is attractive for managing exercise-induced hypoglycemia because the measurement is performed during or immediately after exercise when there is enough sweat to obtain an adequate sample.

"The sensing platform holds considerable promise for efficient diabetes management, and a fully integrated system with a simple readout can be realised toward continuous non-invasive glucose monitoring," the researchers wrote.