Recently, numerous transdermal drug delivery systems have been developed for safe and efficient delivery of biopharmaceuticals. Dissolving microneedles (DMNs) are one such drug delivery system, which have been developed to treat a variety of diseases in a minimally invasive manner. However, current DMN fabrication methods involve a reconstitution process of the therapeutics, which can result in degradation of the therapeutics or limited loading capacity for a reasonable application size. In the present study, we developed self-administrative powder-carrying microneedles (PCMs), lacking a reconstitution step, which implant insulin powder directly inside the skin without using a sticky patch. Compared with DMNs in the same geometries, the PCMs delivered the required dose in a more condensed form without considering insulin solubility and degradation during the fabrication process. Moreover, PCMs showed enhanced long-term stability and prolonged release kinetics, which could be utilized to treat diabetes without apparent safety issues. This implantable PCM technique will greatly impact the future of transdermal drug delivery systems because it is applicable to any type of therapeutic available in a dry powder formulation for a wide variety of biomedical applications.

中文翻译：

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植入式粉末携带式微针，用于经皮递送高剂量胰岛素，具有增强的活性。

近来，已经开发了许多用于安全有效地递送生物药物的透皮药物递送系统。溶解微针（DMN）就是这样一种药物递送系统，已经开发出以微创方式治疗各种疾病的药物。然而，当前的DMN制造方法涉及治疗剂的重构过程，对于合理的应用尺寸，这可能导致治疗剂的降解或有限的负载能力。在本研究中，我们开发了自重构粉末携带式微针（PCMs），该方法缺乏重建步骤，无需使用粘性贴剂即可将胰岛素粉末直接植入皮肤内。与相同几何形状的DMN相比，PCM以更浓缩的形式提供了所需剂量，而没有考虑制造过程中胰岛素的溶解度和降解情况。此外，PCM显示出增强的长期稳定性和延长的释放动力学，可用于治疗糖尿病而没有明显的安全性问题。这种可植入的PCM技术将极大地影响透皮给药系统的未来，因为它适用于干粉制剂中可用于多种生物医学应用的任何类型的治疗剂。