The present work is designed to achieve efficient localised skin delivery of folic acid (FA)–loaded nanostructured lipid carriers (NLCs) to infer efficient treatment of skin photoageing conditions induced via excessive exposure to ultraviolet (UV) radiation. FA NLCs were prepared by high-speed homogenisation followed by ultrasonication. The obtained NLCs revealed high encapsulation efficiencies (89.42–99.26%) with nanometric particle sizes (27.06–85.36 nm) of monodisperse distribution (PDI = 0.137–0.442), zeta potential values >|27| mV, pseudoplastic rheological behaviour, good spreadability (2.25–3.30 cm) and promoted occlusive properties throughout 48 h. Optimised NLC formulations appeared as sphere-shaped particles using transmission electron microscopy, showed improved photostability of FA and prolonged in vitro release profile best fitted to Higuchi diffusion model. Ex vivo permeation and deposition of FA, employing Wistar rat skins, depicted enhanced permeability and existence of FA in skin layers after 6 h. Based on the obtained results, FA-loaded NLC formulations demonstrate a promising modality for anti-photoageing therapy.

本工作旨在实现叶酸（FA）负载的纳米结构脂质载体（NLC）的有效局部皮肤递送，以推断出由于过度暴露于紫外线（UV）辐射而引起的皮肤光老化条件的有效治疗。FA NLC是通过高速均质化然后超声处理制备的。获得的NLC表现出高的包封效率（89.42–99.26％），单分散分布的纳米粒径（27.06–85.36 nm）（PDI = 0.137–0.442），ζ电位值> | 27 |。mV，假塑性流变行为，良好的延展性（2.25-3.30厘米），在整个48小时内具有增强的闭塞特性。优化的NLC制剂使用透射电子显微镜观察时显示为球形颗粒，FA的光稳定性提高，体外作用时间延长最适合Higuchi扩散模型的释放曲线。使用Wistar大鼠皮肤的FA的离体渗透和沉积表明6 h后皮肤层中FA的渗透性增强和存在。根据获得的结果，负载FA的NLC制剂具有抗光老化治疗的前景。