Patchable micro/nanodevices interacting with skin

Patchable devices that interface with the skin across a wide range of size scales, from cellular level down to molecular level, become increasingly attractive in biomedical research. These devices hold the potential for diagnostic and therapeutic functions with exceptional spatiotemporal precision, continuity, and convenience. Further, they afford new opportunities to integrate cloud-based technology and artificial intelligence for a smarter healthcare system. This article reviews recent advances in materials design and assembly techniques for fabricating various patchable devices, with focuses on electrical, thermal, mechanical, and chemical biosensors as well as transdermal gene and drug delivery platforms. A concluding discussion provides perspectives for future developments and outlooks in clinical applications.