Stability and Properties of Ultraviolet Filter Avobenzone under Its Diketo/Enol Tautomerization Induced by Molecular Encapsulation with β-Cyclodextrin.

ABSTRACT: Inclusion complexation of the sunscreen ingredient avobenzone (AVB) with β-cyclodextrin (β-CD) was investigated to improve its aqueous solubility and photostability; another ultraviolet (UV) filter, oxybenzone (OXB), and the phytochemical antioxidant curcumin (CUR) served as a comparison. In this study, the 1-octanol/water partition coefficients, acid dissociation constants, phase-solubility diagrams with β-CD, and ultraviolet-visible (UV-vis) spectral changes induced by UVA1 (365 nm) irradiation were evaluated. β-CD at concentrations 50-100 times that of AVB most effectively protected the photostability of AVB. Additionally, an UVA1-insensitive species with a diketo tautomer, which has an UVC-absorbing band and the potential to cause photodegradation, was stored in the inclusion complex.

SUBMITTER: Kuroda C 

PROVIDER: S-EPMC11755785 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature