Wearable Eye Patch Biosensor for Noninvasive and Simultaneous Detection of Multiple Biomarkers in Human Tears

We develop a novel noninvasive wearable biosensor to simultaneously assay multiple key biomarkers in human tears. The sensor is uniquely designed as a convenient-to-use eye patch that can be easily and comfortably fit under eyes. Different sensing regions on the eye patch are modified with specific chromogenic reagents to selectively determine the hydrogen ion (pH), protein, ascorbic acid, and glucose in tears. The assay takes only one drop of tear (∼20 μL) and a 30 s response time. The resulting color signals from each sensing region on the eye patch are captured and analyzed using a smartphone, and a cloud model based on the internet of things concept is recommended, which can extend the application of the eye patch biosensors in point-of-care testing and health monitoring, especially during the pandemic. Tear detection of the human subjects is performed using the proposed method, and the results display good correlation to parallel measurements using assay kits. The results show the great potential and versatility of the proposed eye patch biosensor for noninvasive determination of diverse tear biomarkers, facilitating the widespread application of the tear-based noninvasive wearable biosensor in emerging personal health care and clinical monitoring fields.