Rapidly separable bubble microneedle patch for effective local anesthesia

In cutaneous cosmetology surgery, local injection or coated anesthetics are generally used to provide analgesia at the treatment site to achieve painless operation. Due to the barrier of corneum, topical cream may cause uncertain dosage and delayed analgesia. Local injection has problems such as pain, infection, and misoperation. Therefore, it is necessary to develop a painless and rapid administration method for local anesthesia. Here, a lidocaine/hyaluronic acid bubble microneedle patch (Lido/HA bMNP) was prepared for rapid drug delivery and efficient analgesia. The bubble structure between microneedles (MNs) and the backing layer allowed the MNs to efficiently penetrate into the skin and remove from the backing layer under shear force to rapidly complete the administration. Drugs were quickly released with the dissolution of HA within 15 s, which immediately played an analgesic effect and lasted for 1 h. Lido/HA bMNP could deliver precise doses to the skin in an extremely short time, which had the advantages of convenient operation, high biosafety, rapid onset of analgesia, and reasonable pain relief time. This patch provided an alternative way for local anesthesia and it was a promising transdermal drug delivery method for the realization of high quality and efficiency “painless medical beauty”.