Diarylethene Photoswitches and 3D Printing to Fabricate Rewearable Colorimetric UV Sensors for Sun Protection

Abstract

AbstractDespite education campaigns linking sun overexposure and skin cancer, it remains one of the leading preventable cancer diagnoses. Skin cancer risk is correlated with overexposure to UV light in sunlight and can be prevented by avoiding exposure. While sun protection can be achieved using sunscreen and clothing, people must be made aware of their risk to facilitate behavior change. Herein, new rewearable UV sensors which overcome the single‐use limitations of other products are presented. These sensors utilize diarylethene photoswitches, which develop a colored appearance upon exposure to UV and are reset to colorless by green light (<10 min). These photoswitches are incorporated into a range of materials, enabling the use of advanced manufacturing to develop highly desirable consumer products. 3D stereolithographic printing is used to prototype sensors, with complex geometries and appealing aesthetics, that can be worn by users. The UV sensitivity of these devices is tuned by incorporating chromophores, meeting the needs of diverse skin types. The colorimetric response allows for direct visual feedback to the user, or quantification using photography, allowing for dosimetry of UV exposure. These new reusable devices aim to reduce people's exposure to UV, while reducing the waste generated by single‐use devices.