High internal phase Pickering emulsions stabilized by surface-modified dialdehyde xylan nanoparticles

Polysaccharide-based particles have attracted considerable attention for stabilizing Pickering emulsions due to their sustainability and biocompatibility. In this study, we developed a novel approach utilizing hemicellulose-based nanoparticles for the stabilization of high internal phase Pickering emulsions (HIPPEs). Polyethylenimine-modified dialdehyde xylan nanoparticles (PEI-DAXNPs) were prepared through periodate oxidation of xylan nanoparticles obtained from esparto pulp, followed by a Schiff base reaction with polyethylenimine (PEI). Oil-in-water HIPPEs were fabricated using PEI-DAXNPs as the sole stabilizer through a one-time homogenization method and exhibited long-term stability after 180 days of storage. Furthermore, gel-like HIPPEs were obtained with a minimum concentration of 0.1 wt% PEI-DAXNPs in the continuous phase and exhibited shear-thinning behavior and promising viscoelastic properties, indicating good processability in the fabrication of soft materials and porous scaffolds. Therefore, the produced PEI-DAXNPs demonstrated significant potential as HIPPE stabilizers, providing inspiration for the valorization of hemicellulose-based nanoparticles.