Laser-induced graphene sensors made affordable with stencil masking

Researchers at the University of Hawaii at Mānoa have unveiled a new technique that could make manufacturing wearable health sensors more accessible and affordable.

Wearable sensors play a crucial role in continuously monitoring vital signs and other health indicators, providing real-time health information that enables proactive, personalized medical care. However, producing these devices often requires specialized facilities and technical expertise, limiting their accessibility and widespread adoption.

The team, led by Assistant Professor Tyler Ray of the Department of Mechanical Engineering (College of Engineering) and the Department of Cellular and Molecular Biology (John A. Burns School of Medicine), introduced an inexpensive stencil-based method to produce sensors. made from laser-induced graphene (LIG), a key material used in wearable sensing platforms.

“This advancement allows us to create high-performance wearable sensors with greater precision and lower cost,” Ray said. “By using a simple metal stencil during the laser patterning process, we have overcome a key limitation of the traditional manufacturing process, opening up new possibilities in sensor design and functionality.”

Using commercially available metal stencils, the UH Mānoa team was able to reduce the minimum feature size from around 120 micrometers to just 45 micrometers. This enables the creation of more complex sensor designs, such as fine-line microarray electrodes, which were previously difficult to achieve with standard laser processing.

“We demonstrated the practicality of our method by fabricating temperature sensors and multi-electrode electrochemical sensors,” explained Ray. “These devices exhibited improved performance, which we attribute to the improved resolution and quality of the graphene patterns.”

The study was published in Biosensors and bioelectronics as part of the journal’s flagship series “Young Scientists in the Americas”.

The study’s lead author was Kaylee M. Clark, with co-authors Deylen T. Nekoba and Kian Laʻi Viernes of the Department of Mechanical Engineering, and Jie Zhou of the Department of Electrical and Computer Engineering.

This innovation builds on Ray’s previous work on the “sweatiner”, a 3D printed wearable sweat sensor that collects and analyzes sweat to provide information on various health issues such as dehydration, fatigue and disease. serious such as diabetes.

The s-LIG method further enhances the potential of accessible health monitoring technologies by enabling the scalable manufacturing of high-performance sensors without relying on traditional, resource-intensive manufacturing routes.