Synthesis of amino acid-grafted cyclodextrins based on dry heat esterification and characterization of their properties.

The inherent limitations of β-cyclodextrin (β-CD), including low solubility and structural rigidity, restrict its delivery efficiency and guest encapsulation capacity. To overcome these drawbacks, this study designed and evaluated aspartic acid (AA)-grafted β-CD (AACD) as a potential multifunctional carrier through a dry-heat esterification reaction. The obtained AACD exhibited about 40-fold higher water solubility than native β-CD and was confirmed to be non-toxic. Notably, the β-CD cavity structure was preserved, enabling high loading capacities of 93.9 % for curcumin and 65 % for cinnamaldehyde. The inclusion complex of AACD with curcumin exhibited high stability under various environmental and physiological conditions. Moreover, pH-responsive antibacterial complexes were formed by cross-linking the introduced amines with aldehydes. Overall, AACD represents a promising multifunctional carrier that combines cavity encapsulation with branched cross-linking, and its complexes with bioactive components hold promising applications in the dietary supplements and functional foods.