Abstract:Objective To investigate the stability of nano-emulsion at different pH levels and its storage stability, and to explore their use in curcumin encapsulation.Methods Nano-emulsion was prepared using the ion complexation method. The amounts of chitosan (CS) and gum Arabic (GA) were optimized based on particle size and Zeta potential. Fourier transform infrared spectroscopy (FTIR) was used to analyze intermolecular interactions, while scanning electron microscopy (SEM) was employed to observe the micro-morphology of CS/GA nano-emulsion. The encapsulation efficiency of curcumin was determined by spectrophotometry.Results When the mass concentrations of CS and GA were 2.5 mg/mL and 1.5 mg/mL, respectively, the prepared nano-emulsion exhibited good stability under acidic conditions, especially when the pH was less than 6.0. When the pH was maintained at 6.0, the polydispersity index (PDI) of the nano-emulsion remained below 0.15 after 28 days, with no precipitation observed. The microstructure of the nano-emulsion exhibited a loose, porous mesh, with the intermolecular forces between the two substances primarily electrostatic. When the mass concentrations of CS and GA were 2.5 mg/mL and 1.5 mg/mL, respectively, the nano-emulsion demonstrated good stability at pH≤6.0, with a curcumin encapsulation efficiency of (93.72±0.04)%.Conclusion CS/GA nano-emulsion can be used as delivery systems for functional ingredients.