In this study, a cell-penetrating peptide named Acylated Steric acid-9 poly-arginine (r₉-SA) was sucessfully synthesized. High performance liquid chromatography (HPLC) and mass spectrometry (MS) were used to characterize the structural formula of r₉-SA. Diclofenac sodium was chosen as a model drug, and the transdermal permeation-enhancing effect of r₉-SA was estimated in vitro. Skin irritation experiment and histopathological observation of tissue sections with HE and Masson staining were performed to analyze the security of r₉-SA. The possible penetration-enhancing mechanism of r₉-SA was characterized with laser scanning confocal microscopy (LSCM), differential scanning calorimetry (DSC), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and laser Raman spectroscopy, respectively. The in vitro penetration study showed that r₉-SA has a promoting effect for enhancing the transdermal penetration of diclofenac sodium. Skin irritation experiment and histopathological observation results showed that r₉-SA has good biocompatibility with skin. The experiments were carried on to characterize the penetration mechanism of r₉ -SA. It was found that r₉-SA may react with the keratin in the stratum corneum (SC), changing its secondary structure and so that drugs can penetrate through SC. In conclusion, all data showed that the r₉-SA could be a safe and effective penetration enhancer for topical delivery of drug.

中文翻译：

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酰化的硬脂酸-9-P（精氨酸）细胞穿透肽作为透皮渗透增强剂的经皮递送应用。

在这项研究中，成功合成了一种名为Acylated Steric acid-9 poly-精氨酸的穿透细胞的肽（r ₉ -SA）。用高效液相色谱（HPLC）和质谱（MS）表征r ₉ -SA的结构式。选择双氯芬酸钠作为模型药物，并在体外评估r ₉ -SA的透皮渗透作用。用HE和Masson染色进行皮肤刺激实验和组织切片的组织病理学观察，以分析r ₉ -SA的安全性。r ₉的可能的渗透增强机制-SA的特征分别是激光扫描共聚焦显微镜（LSCM），差示扫描量热法（DSC），衰减全反射-傅立叶变换红外光谱（ATR-FTIR）和激光拉曼光谱。的体外渗透研究表明的是，R ₉ -SA具有用于增强双氯芬酸钠的透皮渗透促进作用。皮肤刺激实验和组织病理学观察结果表明，r ₉ -SA与皮肤具有良好的生物相容性。进行实验以表征r ₉ -SA的渗透机理。发现r ₉-SA可能与角质层（SC）中的角蛋白发生反应，从而改变其二级结构，从而使药物可以穿透SC。总之，所有数据表明r ₉ -SA可能是局部给药的安全有效的渗透促进剂。