'Smart Contact Lenses' Measure Stress in Real Time

The smart contact lenses developed in this study were made from materials used in the production of actual soft contact lenses. They cause minimal foreign body sensation and are safe. After wearing the smart lenses, bringing a smartphone close to the eye area to tag allows real-time monitoring of accurate stress hormone levels.

[Asia Economy Reporter Junho Hwang] Domestic researchers have developed a smart contact lens that can measure stress hormones in daily life.

The research team led by Jangwoong Park, a research fellow at the Institute for Basic Science (IBS) Nano Medicine Research Division and a professor in the Department of Materials Science and Engineering at Yonsei University, announced on the 9th that, through joint research with Myongji University, they developed a device capable of real-time measurement of cortisol levels, a stress hormone in tears.

Smart Contact Lens for Real-Time Stress Measurement

The smart contact lens developed in this study is designed with a structure that integrates a cortisol sensor, electrodes, and an antenna into a soft lens. The embedded NFC chip processes the electrical signals from the stress hormone sensor and transmits them to a smartphone via the antenna.

This lens is designed with a structure embedding a cortisol sensor, electrodes, and an antenna within a soft lens. The embedded NFC chip processes the electrical signals from the stress hormone sensor and transmits them to a smartphone via the antenna. After wearing this lens, bringing a smartphone close to the eye area to tag it allows for accurate measurement of stress hormone levels.

To develop this lens, the research team implemented a sensor capable of finely measuring cortisol concentration ranges in tears by binding a single antibody of the stress hormone 'cortisol' to a two-dimensional structure, graphene. The concentration is measured through changes in graphene's resistance according to cortisol concentration in tears.

Additionally, they fabricated a wireless communication antenna combining silver nanofibers and silver nanowires, achieving both stretchability and transparency. Each device, including the sensor, antenna, and NFC chip, was connected with stretchable wiring through a 3D printing process and embedded into the soft lens. The NFC chip is connected to the sensor and wirelessly transmits cortisol concentration data based on antigen-antibody reactions to the smartphone.

Enabling Stress Management in Daily Life

Jangwoong Park, Research Fellow, IBS Center for Nanomedicine

The research team also verified performance and safety through wearing experiments. The results confirmed that the lens operates normally while worn and that heat and electromagnetic waves generated by the lens are at levels harmless to the human body. The fabricated lens maintained its shape and function even after being stored in a storage solution.

Research fellow Jangwoong Park stated, "By accurately measuring stress levels in real time, we developed a smart contact lens that helps manage stress in daily life, and we expect it to be utilized not only in the mobile healthcare industry but also in various medical fields." The research results were published in the international academic journal Science Advances.