Pepsin and trypsin coronas on starch nanoparticles: size-dependent modulation of curcumin release and bioactivity

This study explored the influence of different sizes curcumin-loaded starch nanoparticles on protein corona formation and their interactions with pepsin and trypsin. SEM and AFM results showed the spherical shape of the nanoparticles. FTIR and fluorescence spectroscopy results reported the formation of enzymes coronas was primarily driven by hydrophobic interactions and hydrogen bonding. XRD results showed that curcumin was encapsulated within the nanoparticles, while the enzyme corona formation did not affect the stable encapsulation of curcumin. QCM-D results suggested that smaller-sized nanoparticles were more favorable for tight adsorption of digestive enzymes, thereby promoting protein corona formation. The relative activity of pepsin remained stable after protein corona formation, whereas trypsin relative activity increased with increasing nanoparticle size, suggesting the presence of enzyme-specific conformational adaptations. These findings reported the complex nano-bio interface between polyphenol-based nanoparticles and digestive enzymes, providing key insights into the design of delivery systems aimed at enhancing bioavailability.