Schiff Base Mediated Food-Derived Peptide Supramolecular Self-Assembly as Curcumin Carriers

The fusion assembly strategy of supramolecular chemistry combined with dynamic covalent chemistry has provided novel insights into the design of precision nutrition and intelligent drug delivery carriers. This work involved the development of a supramolecular self-assembly originating from entropy- and enthalpy-driven dynamic covalent bonding on Schiff bases between egg white-derived peptide Gln-Ile-Gly-Leu-Phe (QIGLF) and glutaraldehyde (GA), denoted QIGLF-GA. The assembly exhibited outstanding assembly characteristics and multiwavelength autofluorescence properties. Benefiting from the potent facilitation of the dynamic covalent interaction of Schiff base on the noncovalent assembly force network, QIGLF-GA was afforded an encapsulation capacity of curcumin (Cur) of more than 22% (≫ 10%) and rationally inhibited P-glycoprotein-mediated cellular efflux and markedly elevated the efficacy of Cur in overcoming the intestinal epithelial absorption barrier to the circulation with the help of endocytosis. Furthermore, QIGLF-GA-Cur features responsive release under weakly acidic conditions, which dramatically contributes to the intracellular bioavailability of Cur.