Seong Keum-Yong, Kim Min Jae, Lee Hyeseon, Kim Sodam, Kim Semin, Kim Hoon-Soo, Jung Eui-Man, An Beum-Soo, Yang Seung Yun
Department of Biomaterials Science (BK21 Four Program), Life and Industry Convergence Institute, Pusan National University, Miryang 50463, Republic of Korea.
Department of Biomaterials Science (BK21 Four Program), Life and Industry Convergence Institute, Pusan National University, Miryang 50463, Republic of Korea; Institute for Future Earth, Pusan National University, Busan 46241, Republic of Korea.
Int J Pharm. 2025 Jan 25;669:125020. doi: 10.1016/j.ijpharm.2024.125020. Epub 2024 Dec 1.
With increasing clinical demands for painless and easy administration of medications, such as for hair loss, microneedles (MNs) have been widely exploited for facilitating drug permeation in a minimally invasive manner. However, precise dose control and long-term drug delivery without the infection risk through punctured holes have remained unresolved. Herein, we developed swellable microneedles (MNs) with an air-pocket structure, enabling shear-induced implantation inside the skin. The air-pocket MNs (AP-MNs) were prepared by one-step molding process with genipin-crosslinked gelatin solutions. This MN design induced mechanical difference following insertion due to selective hydration at the inserted MN tips, causing them to break at the interface between the swollen tip and the non-inserted column. The AP-MNs (80-90 %) were embedded into the skin and played a barrier function by tightly sealing punctured holes. Minoxidil (MXD) for hair loss treatment were quantitatively loaded in the AP-MNs depending on swellable tip heights, with 90 % of loaded MXD in the AP-MN tips released over 48 h. In animal studies, the MXD-loaded AP-MNs exhibited higher efficiency than topical application for hair loss treatment. These results indicate that the design of shear-induced embeddable MNs could provide a high-efficiency, convenient, safe, and potentially self-administered method for drug delivery.
随着临床对无痛且易于给药的需求不断增加，例如针对脱发治疗，微针已被广泛用于以微创方式促进药物渗透。然而，精确的剂量控制以及无针刺孔感染风险的长期药物递送问题仍未得到解决。在此，我们开发了具有气穴结构的可膨胀微针，能够通过剪切诱导植入皮肤内部。气穴微针（AP-MNs）通过与京尼平交联的明胶溶液一步成型工艺制备。这种微针设计在插入后由于插入的微针尖端选择性水合而导致机械差异，使其在肿胀尖端与未插入柱体之间的界面处断裂。80% - 90%的AP-MNs嵌入皮肤，并通过紧密密封针刺孔起到屏障作用。用于脱发治疗的米诺地尔（MXD）根据可膨胀尖端高度定量加载到AP-MNs中，90%加载在AP-MN尖端的MXD在48小时内释放。在动物研究中，负载MXD的AP-MNs在脱发治疗方面表现出比局部应用更高的效率。这些结果表明，剪切诱导可植入微针的设计可为药物递送提供一种高效、便捷、安全且可能可自我给药的方法。
