New Strategies for Transdermal Delivery of Active Components from Traditional Chinese Medicine: Research Progress and Prospects of Dissolving Microneedle Technology

Abstract

Traditional Chinese medicine (TCM), guided by the holistic concept and the principle of preventive treatment of disease, has unique advantages in the prevention and treatment of chronic, inflammatory, immune-related, and other complex diseases. However, most active components of TCM suffer from poor water solubility, limited stability, rapid in vivo metabolism, and low bioavailability. Conventional oral, injectable, and topical routes of administration have obvious limitations, which severely restrict the clinical application of TCM active components. Transdermal drug delivery can avoid the hepatic first-pass effect and improve drug utilization efficiency, whereas the stratum corneum barrier of the skin remains the key challenge limiting transdermal absorption of TCM active components. As a novel minimally invasive transdermal delivery technology, dissolving microneedles can overcome the skin barrier through an integrated “pierce–dissolve–release” mode. They offer multiple advantages, including good biocompatibility, residue-free application, minimal invasiveness, painlessness, and controllable drug release, thereby providing an innovative solution for efficient transdermal delivery of TCM active components. This article systematically reviews the types and selection principles of matrix materials for dissolving microneedles, summarizes the technical characteristics of mainstream fabrication methods such as centrifugation molding, vacuum molding, 3D printing, and droplet-born air blowing, and outlines various loading strategies for TCM active components. Meanwhile, it reviews the current applications of dissolving microneedles for TCM delivery in skin diseases, autoimmune diseases, pain-related disorders, hair disorders, and medical aesthetic repair. Furthermore, this article analyzes current bottlenecks of this technology, including limited drug loading capacity, insufficient mechanical strength, lack of standardized evaluation systems, and inadequate evidence for clinical translation, aiming to provide theoretical references and technical insights for structural optimization, process improvement, industrialization, and clinical translational application of dissolving microneedle formulations containing TCM active components.