Progress in wearable devices for drug delivery

Wearable devices have good portability and imperceptibility， realizing expected functions after being worn. Drug delivery refers to delivering drugs into the body with suitable carriers or techniques to generate therapeutic effects to improve the stability and bioavailability of drugs.The application of wearable devices in drug delivery can rationally release drugs when receiving disease signals or user orders and monitor in-vivo drug concentrations， reducing the dependency of doctors or hospitals， and achieving optimal disease treatment timing and outcomes. Wearable drug delivery systems can be worn directly on the body surface and are non-invasive and self-administered. Microneedle-skin patches， wound healing patches， and smart contact lenses are popular wearable devices explored in drug delivery. This review is a summary of the application of wearable devices in disease treatment， such as diabetes， wound healing， eye diseases， cancer， and other diseases， and drug delivery in recent five years， summarizing the challenges for the development of wearable drug delivery systems， and prospecting its development direction.