Hyperpigmentation, a prevalent dermatological condition characterized by melanin overproduction, poses treatment challenges due to the hydrophilicity of alpha-arbutin, a widely utilized tyrosinase inhibitor. This study investigates the efficacy of dissolving microneedles (DMNs) in augmenting skin permeation for alpha-arbutin delivery to the targeted epidermal site.

Porcine full-thickness skin was employed in a 24-hour Franz cell study, commencing with the assessment of commercial alpha-arbutin-containing products. Solid steel microneedles (CMNs) from Dermapen® were utilized as both pre- and post-treatment modalities to evaluate the influence of different applications on alpha-arbutin delivery. Additionally, alpha-arbutin-loaded polyvinylpyrrolidone-co-vinyl acetate (PVPVA) DMNs, containing 2 % w/w alpha-arbutin, were fabricated and examined for their permeation-enhancing capabilities. HPLC analysis and 3D Orbitrap Secondary Ion Mass Spectrometry (OrbiSIMS) were employed to quantify and visualize alpha-arbutin in various Franz cell components.

Results indicate that alpha-arbutin permeation to the skin was restricted (less than 1 %) without microneedle application and significantly increased by 6-fold (4–5 %) with post-treatment CMNs and DMNs, but not with pre-treatment CMNs. Notably, DMNs exhibited a more sustainable and robust capacity than post-treatment CMNs. OrbiSIMS imaging analysis revealed that DMNs visually enhance skin permeation of alpha-arbutin by delivering the compound to the basal layer of the targeted skin location. Overall, this study underscores the potential of DMNs as a promising delivery system for promoting targeted intradermal delivery of alpha-arbutin, providing a comprehensive exploration of various methodologies to identify innovative and improved microneedle approaches for alpha-arbutin permeation.

色素沉着是一种以黑色素过度生成为特征的普遍皮肤病，由于α-熊果苷（一种广泛使用的酪氨酸酶抑制剂）的亲水性，给治疗带来了挑战。本研究调查了溶解微针 (DMN) 在增强皮肤渗透性以将 α-熊果苷输送到目标表皮部位方面的功效。

24 小时 Franz 细胞研究采用猪全层皮肤，从评估商业含 α-熊果苷产品开始。Dermapen® 的实心钢微针 (CMN) 被用作治疗前和治疗后的方式，以评估不同应用对 α-熊果苷输送的影响。此外，还制备了负载 α-熊果苷的聚乙烯吡咯烷酮-醋酸乙烯酯 (PVPVA) DMN，其中含有 2% w/w α-熊果苷，并检查了其渗透增强能力。采用 HPLC 分析和 3D Orbitrap 二次离子质谱 (OrbiSIMS) 对各种 Franz 细胞成分中的 α-熊果苷进行定量和可视化。

结果表明，在不使用微针的情况下，α-熊果苷对皮肤的渗透受到限制（小于 1%），并且在治疗后 CMN 和 DMN 中显着增加了 6 倍（4-5%），但在治疗前 CMN 中则不然。值得注意的是，DMN 表现出比治疗后 CMN 更可持续、更强大的能力。OrbiSIMS 成像分析显示，DMN 通过将化合物递送至目标皮肤位置的基底层，在视觉上增强了 α-熊果苷的皮肤渗透性。总体而言，这项研究强调了 DMN 作为一种有前景的递送系统的潜力，可促进 α-熊果苷的靶向皮内递送，提供对各种方法的全面探索，以确定创新和改进的微针方法用于 α-熊果苷渗透。