A double-package delivery system based on κ-carrageenan hydrogels and vitamin E/highly branched cyclic dextrin composites: Structural characteristics and release behavior

To overcome the limitations of conventional vitamin E (VE) delivery systems, a double-package system comprising κ-carrageenan hydrogels and VE/highly branched cyclodextrin (HBCD) composites was developed and systematically evaluated for structural characteristics and release behavior. The results demonstrated that HBCD encapsulation of VE formed stable composites with high encapsulation efficiency (81.72 %) and thermostability (325.86 °C), which facilitated the ordered alignment and helical aggregation of κ-carrageenan chains to build a continuous and uniform hydrogel network. The 2 % composites within the κ-carrageenan network strengthened hydrogen-bond interaction and generated a secondary micro-network, thereby enhancing structural integrity (758.39 Pa) and freeze–thaw stability (a 30 % reduction in syneresis) of the double-package system. Importantly, the inner–outer network effectively protected VE under gastric conditions and enabled controlled intestinal release (> 60 %). Overall, this study underscores the potential of HBCD as a wall material and provides a strategy for the design of double-package delivery systems.