Multivalent Supramolecular Assembly Based on Polyanionic Cyclodextrin for the Controlled Release of Curcumin

Abstract

Multivalent supramolecular assemblies based on cyclodextrins and biomacromolecules have attracted considerable attention from researchers owing to their wide application in fields such as cell imaging, drug delivery, and food preservation. Herein, ternary supramolecular nanoassemblies are constructed by per‐[6‐deoxy‐mercaptopropionic acid]‐ γ ‐cyclodextrin (SgCD), chitosan (CS), and curcumin (Cur, a natural compound from a herb), displaying not only pH‐responsive reversible assembly and disassembly but also the controlled release of drug. Initially, two types of nanoparticles (SgCD–CS) with average sizes of 188 and 342 nm are facilely fabricated using anionic SgCD and cationic CS with different deacetylation degrees, driven by the multivalent electrostatic interactions between them. These SgCD–CS nanoparticles exhibit excellent stability and pH‐responsiveness. Subsequently, taking advantage of the strong host–guest interaction between SgCD and Cur, the SgCD–CS nanoparticles efficiently load Cur, and the ternary supramolecular assemblies show superior antioxidant activity compared to free Cur, as confirmed by DPPH radical scavenging assays. Notably, Cur is stably encapsulated within the SgCD–CS nanoparticles under acidic conditions but released under alkaline conditions, highlighting the system’s potential for targeted delivery and stimuli‐responsive release. The pH sensitivity and loading/release capability for larger‐sized bioactive molecules render the SgCD–CS nanoparticles promising candidates for applications in the fields of functional foods and pharmaceuticals.