Mechanically Activated Starch Reticular Nanostructure Traps Ferulic Acid as a Structural and Functional Cargo.

Abstract

Upon the scalable utilization of polyphenols, the design of their composites with polymers has received a great deal of attention. However, the starch polymer has a weak loading of hydrophobic polyphenols typically through noncovalent interactions without biochemical catalysts. Here, we tailor a reticular starch nanostructure from a starch nanosphere precursor (preSNS) that traps ferulic acid (FA) via esterification. The preSNS-FA network is activated by a green physical method via dynamic high-pressure microfluidization, exhibiting an exceptionally higher content of FA (∼38.0%) compared with the conventional starch group (only ∼1.5%). SEM, FTIR, XRD, 13C NMR, 1H NMR, and XPS results as well as molecular dynamics simulation comprehensively confirm the changes in architecture and hydrogen bonding modes with the formation of -COOR-. The preSNS-FA network also has an enzymatic hydrolysis resistance (up to 83.8%). Collectively, this work establishes a high-performance and catalyst-free synthetic route toward an esterified polyphenol complex network with potential applications in nutrient delivery, food packaging, and agriculture fields.