Sodium cholate-coated Olea europaea polyphenol nanoliposomes: Preparation, stability, release, and bioactivity

Ultra-flexible nanoliposomes (UNL) coated with sodium cholate were fabricated using the thin film hydration technique to encapsulate oleocanthal (OLEO), oleacein (OLEA), oleuropein (OLEU), and hydroxytyrosol (HT) for improving their stability and bioactivity. Their physicochemical properties were further validated through DLS, FTIR, XRD, TGA, and DSC analyses. Negative-staining TEM imaging revealed well-dispersed UNL with laminar vesicles inside. Additionally, their transdermal studies in vitro demonstrated that UNL enhanced the cumulative release of OLEO, OLEA, OLEU, and HT by 3.13, 2.76, 2.59, and 2.83 times, respectively. Furthermore, their release mechanisms were better approximated the Peppas-Sahlin model rather than the Korsmeyer-Peppas and Higuchi models, which governed by Fickian diffusion. Moreover, comparing to their compounds, UNL structure exhibited improved their antioxidant and cytotoxicity properties, highlighting their potential as effective delivery agents in humans. These results offer a novel approach for stabilizing biologically active polyphenols from Olea europaea, paving the way for enhanced human health applications.