Development of Efficient Supramolecular Photostabilizer for Carotenoids and Retinoids: Analyses and Application Research.

BACKGROUND: Carotenoids and retinol are well known for their potent antioxidant and biological properties in pharmaceuticals, foods, and cosmetics. However, their poor photostability presents a significant challenge that cannot be effectively addressed through simple formulation strategies such as encapsulation. Although photostabilizers are commonly employed to enhance product photostability, there remains a lack of highly water-soluble and legitimate stabilizers suitable for commercial cosmetic applications. AIMS: To develop a novel aqueous-phase photostabilizer simultaneously boosting carotenoid and retinol shelf-life in cosmetics and meeting global safety standards. Underlying mechanism and application are investigated. METHODS: Micellar supramolecular complex crocin-Na2GA was prepared by mechanochemistry; thermal stability, storage stability, and photo-oxidative degradation were tested. Then, photoprotection of carotenoids and retinoids by crocin-Na2GA in aqua solution, cream-based formulations, and on an artificial skin model was tested. Finally, cyclic voltammetry was applied for mechanism research. RESULTS: Experiments demonstrated that the light-induced degradation of astaxanthin, β-carotene, and retinol in aqueous solutions, cream formulations, and on skin was significantly reduced upon the addition of crocin-Na2GA. These findings indicated that crocin-Na2GA possessed remarkable photoprotective properties. Mechanistic studies further revealed that within the stable nano micellar system of crocin-Na2GA, crocin was readily photoactivated and scavenged photoinduced radicals through a self-sacrificial mechanism, thereby preventing the photodegradation of active constituents during the storage and application phases of creams. CONCLUSIONS: Collectively, these results highlight the potential of crocin-Na2GA as a highly efficient, safe, and cost-effective photostabilizer, making it a promising candidate for incorporation into cosmetic formulations.