Biomimetic polydopamine-intercalated MgAl-layered double hydroxide for effective skin photoprotection and photodamage recovery.

Excessive ultraviolet (UV) radiation is harmful to human health, leading to a range of skin issues including photoaging, sunburn, and skin cancer. Using sunscreen can help alleviate or provide temporary protection against the harmful effects of UV radiation. Commercial sunscreens frequently have low effectiveness and raise safety concerns. Therefore, a novel biocompatible polydopamine-intercalated MgAl-layered double hydroxides nanocomposite (PDA-LDH) was synthesized via in situ oxidation of dopamine within the interlayer of LDH at room temperature and without any additives. LDH can serve as an effective base to facilitate the formation of PDA without the need for an additional base, due to the ordered arrangement of basic hydroxyl groups on the surface of the LDH. The intercalation of PDA in the LDH interlayer ensures good biosafety, effective UV shielding, and excellent antioxidative and anti-inflammatory properties of PDA-LDH, making it suitable for skin photoprotection and the repair of photodamaged skin. PDA-LDH is poised to be a promising next-generation biomimetic sunscreen, designed to assist in the photoprotection and repair of photodamaged skin.