Skin-customized wearable device adhesive without skin damage

Abstract

Wearable medical devices are gaining popularity owing to their potential for seamless integration with the human body and long-term monitoring of physiological activity. However, conventional adhesives were developed based on the assumption of healthy adult skin and may not account for variations in skin characteristics across different species, environments, and body parts. Consequently, the adhesive strength of wearable devices may significantly differ depending on the skin surface to which they are attached, potentially causing skin damage. In this study, we developed a customized wearable-device adhesive without skin damage by analyzing the characteristics of the skin surface based on oil and water content and roughness according to different species and parts. Our findings demonstrated that increased root-mean-square roughness of the skin surface led to reduced contact area and decreased adhesion force between the polydimethylsiloxane (PDMS) pad and skin surface. Surprisingly, hairless skin exhibited 1.5 times higher adhesion strength than hairy skin due to stronger molecular forces resulting from the higher surface energy of the skin. Additionally, the hole-patterned PDMS pad on sweaty skin displayed improved adhesion properties compared to the cylinder-patterned PDMS pad. Therefore, customized wearable adhesives provide an effective strategy for developing skin-damage-free wearable devices. © 2023 Wiley Periodicals LLC.