Ultra-intimate hydrogel hybrid skin patch with asymmetric elastomeric spatula-like cylinders

Intelligent bioinspired adhesive devices are attracting attention as a tool for the treatment of various skin diseases. Fully compliant skin contact is crucial for consistent effective therapy through a transdermal interface, for which structured materials for an intelligent adhesion should be developed. It is also important to design such skin patch with non-invasive, human-friendly treatment material and small structural interface for effective treatment of skin disorder. Herein, we fabricated the asymmetric elastomeric adhesive structures that mimics the spatula-like setae of diving beetles capable of directional adhesion and nanoporous hydrogel. Our hybrid skin patch devices demonstrated reversible and directional adhesion to the complex skin surface, while allowing the drug-containing hydrogel to be in ultra-intimate contact with the non-flat skin with hierarchical roughness. With the aid of diving beetle-inspired adhesive, this extraordinary conformal hydrogel interface provides an efficient strategy for the treatment of skin diseases such as atopic dermatitis.