Interactions, properties and lipid digestibility of attractive Pickering emulgels formed by sequential addition of oppositely charged nanopolysaccharides†

Abstract

Emulsion gels (emulgels) have emerged as cost-effective and versatile platforms in formulation engineering. In this study, we introduce Attractive Pickering Emulgels (APEGs), stabilized by the synergistic action of two oppositely charged green nanoparticles, e.g., chitin nanofibers (ChNF) and cellulose nanocrystals (CNC). The CNC, featuring anionic sulfate half-ester groups, and the cationic ChNF, possessing amine groups, form adhesive bridging networks within the continuous aqueous phase, effectively inhibiting oil droplet coalescence. This network supports micro-clustering, significantly increasing the effective droplet volume fraction by entrapping substantial amounts of the continuous phase. Consequently, the emulgels demonstrate a robust viscoelastic response and effectively modulate lipid digestibility, as evidenced by a 30% reduction in free fatty acid (FFA) release at high oil fractions (70 wt%) during in vitro digestion. The stabilization mechanism relies on noncovalent interactions and nanoparticle coassembly, validated through quartz crystal microgravimetry and molecular dynamics simulations. APEGs present significant potential for advancing sustainable nanotechnologies in pharmaceutical, food, and health formulations.