Lidocaine, a commonly used local anesthetic, has recently been developed into a number of ointment products to treat hemorrhoids. This study examined its efficient delivery to the dermis through the pharmaceutical improvement of hemorrhoid treatment ointments. We attempted to increase the amount of skin deposition of lidocaine by forming a nanoemulsion through the self-nanoemulsifying effect that occurs when glycerol monostearate (GMS) is saturated with water. Using Raman mapping, the depth of penetration of lidocaine was visualized and confirmed, and the local anesthetic effect was evaluated via an in vivo tail-flick test. Evaluation of the physicochemical properties confirmed that lidocaine was amorphous and evenly dispersed in the ointment. The in vitro dissolution test confirmed that the nanoemulsifying effect of GMS accelerated the release of the drug from the ointment. At a specific concentration of GMS, lidocaine penetrated deeper into the dermis; the in vitro permeation test showed similar results. When compared with reference product A in the tail-flick test, the L5 and L6 compounds containing GMS had a significantly higher anesthetic effect. Altogether, the self-nanoemulsifying effect of GMS accelerated the release of lidocaine from the ointment. The compound with 5% GMS, the lowest concentration that saturated the dermis, was deemed most appropriate.

中文翻译：

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用于局部给药的含有单硬脂酸甘油酯的利多卡因自纳米乳化软膏的制备和体内评价

利多卡因是一种常用的局部麻醉剂，最近已被开发成许多用于治疗痔疮的软膏产品。本研究通过对痔疮治疗软膏的药物改进，检查了其向真皮的有效递送。我们试图通过单硬脂酸甘油酯 (GMS) 与水饱和时发生的自纳米乳化效应形成纳米乳液，从而增加利多卡因的皮肤沉积量。使用拉曼图，可视化并确认利多卡因的渗透深度，并通过体内甩尾试验评估局部麻醉效果。理化性质评价证实，利多卡因呈无定形，均匀分散在软膏中。体外溶出试验证实，GMS的纳米乳化作用加速了药物从软膏中的释放。在特定浓度的 GMS 下，利多卡因深入真皮层；体外渗透试验显示了类似的结果。在甩尾试验中与参比品A相比，含GMS的L5和L6化合物具有明显更高的麻醉效果。总之，GMS的自纳米乳化作用加速了利多卡因从软膏中的释放。具有 5% GMS（使真皮饱和的最低浓度）的化合物被认为是最合适的。含有 GMS 的 L5 和 L6 化合物具有明显更高的麻醉效果。总之，GMS的自纳米乳化作用加速了利多卡因从软膏中的释放。具有 5% GMS（使真皮饱和的最低浓度）的化合物被认为是最合适的。含有 GMS 的 L5 和 L6 化合物具有明显更高的麻醉效果。总之，GMS的自纳米乳化作用加速了利多卡因从软膏中的释放。具有 5% GMS（使真皮饱和的最低浓度）的化合物被认为是最合适的。