Preparation of chitosan/gum Arabic nanoparticles and their use as novel stabilizers in oil/water Pickering emulsions

Recently, there has been a renewed interest in Pickering emulsions owing to their surfactant-free nature, and the use of natural-based particles as stabilizers became a priority due to the applications they can enable. In this work, chitosan/gum Arabic (CH/GA) nanoparticles were synthesized and tested as novel stabilizers. Among the tested CH/GA weight ratios, the particles prepared using 1:1 ratio exhibited near-neutral wettability, an average size of 108.6 nm and a zeta potential of 56.3 my. Pickering emulsions prepared from these particle dispersions (1.5% w/v), and high oil volume fractions (phi = 0.6, 0.7), have shown high storage stability. Moreover, confocal laser scanning microscopy confirmed the o/w type and the effective adsorption of the nanoparticles at the oil/water interface forming a barrier against droplets coalescence. The emulsions have shown shear-thinning and elastic-like behavior. These findings open new avenues for using these emulsions as novel delivery systems, e.g. in cosmetic and food applications.