School of Life Science, Beijing Institute of Technology, Beijing, 100081, China.
Institute of Quartermaster Engineering and Technology, Institute of System and Engineering, Academy of Military Sciences of People's Liberation Army, Beijing, 100010, China.
Lab Chip. 2022 Nov 22;22(23):4521-4530. doi: 10.1039/d2lc00505k.
Photodynamic therapy (PDT), as a globally accepted method for treating different forms of skin or mucosal disorders, requires efficient co-delivery of photosensitizers and corresponding therapeutic light. The adverse effects of intravenous injection of photosensitizers have been reduced by the development of microneedle arrays for transdermal local photosensitizer delivery. However, the drawbacks of the only available therapeutic light delivery method at the moment, which is directly applying light to the skin surface, are yet to be improved. This study presents a new strategy in which therapeutic light and photosensitizer were transdermally co-delivered into local tissues. A flexible dual-function microneedle array (DfMNA) which contains 400 microneedles was developed. Each microneedle consists of a dissolvable needle tip (140 μm in height) for delivering the photosensitizer and a transparent needle body (660 μm in height) for guiding therapeutic light. Using port-wine stains, which is a frequently occurring skin disorder caused by vascular malformation, as a model disease, the effectiveness of DfMNA mediated PDT has been verified on mice. Compared with the standard operation procedure of clinical PDT, the DfMNA decreases the amount of photosensitizer from 300 μg to 0.5 μg and reduces therapeutic light irradiance from 100 mW cm to 60 mW cm while realizing better treatment effects. As a result, the skin damage and the burden on the metabolic system have been alleviated. The DfMNA has a remarkably reduced photosensitizer amount and, for the first time, realized transdermal delivery of therapeutic light for PDT, thus avoiding the disadvantages of existing PDT methodologies.
光动力疗法（PDT）作为一种治疗不同形式皮肤或黏膜疾病的全球认可方法，需要将光敏剂和相应的治疗光有效地递送到病灶部位。通过开发微针阵列用于经皮局部光敏剂递送来减少静脉注射光敏剂的不良反应。然而，目前唯一可用的治疗光递送方法，即直接将光应用于皮肤表面，仍有待改进。本研究提出了一种新的策略，即将治疗光和光敏剂经皮递送到局部组织中。开发了一种包含 400 个微针的柔性双功能微针阵列（DfMNA）。每个微针由一个可溶解的针尖（高 140μm）组成，用于递送光敏剂，和一个透明的针体（高 660μm）用于引导治疗光。以葡萄酒色斑（一种由血管畸形引起的常见皮肤疾病）作为模型疾病，验证了 DfMNA 介导的 PDT 的有效性。与临床 PDT 的标准操作程序相比，DfMNA 将光敏剂的用量从 300μg 减少到 0.5μg，并将治疗光辐照度从 100mW cm 减少到 60mW cm，同时实现了更好的治疗效果。因此，减轻了皮肤损伤和代谢系统的负担。DfMNA 的光敏剂用量显著减少，并且首次实现了治疗光的经皮递送给 PDT，从而避免了现有 PDT 方法的缺点。
