Enhanced stability of vitamin A palmitate microencapsulated by γ-cyclodextrin metal-organic frameworks.

gamma-Cyclodextrin metal-organic frameworks (gamma-CD-MOFs) are highly porous and bio-friendly novel materials formed by gamma-CD as an organic ligand and potassium ion as an inorganic metal centre. The aim of this study was to enhance the stability of vitamin A palmitate (VAP) using y-CDMOFs as the carrier. Herein, gamma-CD-MOFs displayed VAP microencapsulating capacity of 9.77 +/- 0.24% with molar ratio as n(MOFs) : n(VAP) = 3.2:1.0. It was important to find that the improved stability of VAP microencapsulated by y-CD-MOFs without addition of any antioxidant(s) was better than that of the best available reference product in the market, with 1.6-fold elongated half-life. The protecting mechanism of gamma-CD-MOFs for VAP contributed that VAP molecules preferentially curled inside the cavities of dual gamma-CD pairs in gamma-CD-MOFs. It was proved that gamma-CDMOFs were an efficient new carrier to deliver and protect VAP for food and pharmaceutical applications.