Faculdade de Farmácia Universidade Federal do Rio grande do Sul, Porto Alegre, Brazil.
Programa de Pós-Graduação em Ciências Farmacêuticas, PPGCF, Universidade Federal do Rio grande do Sul, Porto Alegre, Brazil.
Skin Pharmacol Physiol. 2022;35(5):291-298. doi: 10.1159/000525176. Epub 2022 Jun 15.
Sunscreens are substances applied on the skin surface to protect the skin from the harmful effects of UV light. Nanoparticles can increase the retention time of the sunscreen on the skin surface and its efficacy, by acting as physical barriers. The present investigation aimed to evaluate the influence of the chitosan coating of benzophenone-3-loaded lipid-core nanocapsules (CH-LCN) on the skin adhesion and photoprotective effect of the sunscreen.
CH-LNC were obtained by the interfacial deposition of preformed polymer. A suitable semisolid formulation was obtained by using hydroxyethyl cellulose as the gel-forming polymer. Skin adhesion experiments were performed in vitro by applying the formulation on porcine skin and keeping it under water at 32 °C for up to 60 min. Photoprotective effect was analyzed in vitro by the capacity of the formulations to protect a photo unstable substance (resveratrol) from degradation under UV light.
CH-LNC presented size of around 150 nm, with low polydispersity, positive zeta potential, due to chitosan, and benzophenone-3 encapsulation efficiency of close to 100% (3 mg/mL). The proposed gel presented suitable consistence and pH for skin application and benzophenone-3 concentration of around 3 mg/g. Although coated and uncoated lipid-core nanocapsules increased benzophenone-3 skin adhesion after 10 min of water immersion, only the nanoparticles coated with chitosan were able to do so after 60 min. The chitosan coating of the nanocapsules increased the photoprotection of the sunscreen under UVA and UVB light after 60 min of exposure, probably due to the film-forming properties of chitosan.
The chitosan coating of CH-LCN increased the skin adhesion and the photoprotective effect of the sunscreen.
防晒霜是涂在皮肤表面的物质，用于保护皮肤免受紫外线的有害影响。纳米粒子可以通过充当物理屏障，增加防晒霜在皮肤表面的滞留时间和功效。本研究旨在评估壳聚糖涂覆二苯甲酮-3 负载的脂质核纳米囊（CH-LCN）对防晒霜的皮肤粘附和光保护作用的影响。
CH-LCN 通过预形成聚合物的界面沉积获得。通过使用羟乙基纤维素作为凝胶形成聚合物，获得合适的半固体配方。通过将制剂涂在猪皮上并在 32°C 的水下保持 60 分钟，在体外进行皮肤粘附实验。通过制剂保护光不稳定物质（白藜芦醇）免受紫外线降解的能力，在体外分析光保护效果。
CH-LNC 粒径约为 150nm，具有低多分散性、正 zeta 电位，这归因于壳聚糖，且二苯甲酮-3 的包封效率接近 100%（3mg/mL）。所提出的凝胶具有适合皮肤应用的合适稠度和 pH 值，以及约 3mg/g 的二苯甲酮-3 浓度。尽管涂覆和未涂覆的脂质核纳米囊在水浸泡 10 分钟后增加了二苯甲酮-3 的皮肤粘附，但只有涂覆壳聚糖的纳米囊在 60 分钟后才能做到这一点。纳米囊的壳聚糖涂层增加了防晒霜在 UVA 和 UVB 光下的光保护作用 60 分钟后，这可能是由于壳聚糖的成膜特性。
CH-LCN 的壳聚糖涂层增加了防晒霜的皮肤粘附和光保护作用。
