Ultrarapid‐Acting Microneedles for Immediate Delivery of Biotherapeutics

Abstract Subcutaneous (SC) injection is a common administration route for rapid and efficient delivery of biotherapeutics. However, syringe‐based injections usually require professional assistance and are associated with pain and potential risks of infections, thus leading to undesired patient compliance and poor life quality. Herein, this work presents an ultrarapid‐acting microneedle (URA‐MN) patch for immediate transdermal delivery of therapeutics in a minimally invasive manner. Effervescent agents are incorporated into the tip of URA‐MN for rapid generation of CO₂ bubbles upon insertion into the skin, immediately powering the biotherapeutics release within a few minutes. The release kinetics of diverse agents including liraglutide (LRT), insulin, and heparin from the URA‐MN patches are evaluated in three different mouse models, and the rapid release of biotherapeutics and potent therapeutic effects are achieved with only 5 min administration. Noteworthily, attributed to the short application duration and negligible residuals of MN matrix remaining in the skin, the URA‐MN patch shows desirable biocompatibility after six‐week administration.