Flexible PEGDA-based microneedle patches with detachable PVP–CD arrowheads for transdermal drug delivery

Abstract

Traditional drug administration using hypodermic needles not only causes severe pain and bleeding to the patients, but also requires professional operation by trained healthcare practitioners. Recently, various types of microneedle patches have been developed for pain-free subcutaneous delivery of drugs and vaccines. However, for most existing microneedle devices, the backing layer where the microneedles grow remains attached to the skin until complete release of the drug. In this work, a novel microneedle patch is designed and fabricated by assembling drug-loaded polyvinylpyrrolidone–cyclodextrin (PVP–CD) arrowheads that are detachable from polyethylene glycol diacrylate (PEGDA)-based needle shafts. When applying this patch onto the skin, the drug-loaded polymer arrowheads with sharp tips can effectively penetrate through the epidermis. Then the backing substrate with blunt PEGDA shafts can be peeled off and discarded shortly after administration, while the drug-loaded polymer arrowheads remain embedded in the dermis for further dissolution and drug release. This simple and convenient drug administration using detachable microneedle patches is very user-friendly and also can effectively address the cosmetic concerns of the patients. Additionally, this patch device features a flexible substrate and thus can adhere to the lesion surface with any curvature. The drug delivery based on this versatile microneedle patch is expected to create new therapeutic modalities for treating various local and systemic diseases with the advantages of convenience, safety and self-administration.