Polysaccharide-based nanoparticles by chitosan and gum arabic polyelectrolyte complexation as carriers for curcumin

This study developed the polysaccharide-based nanoparticles by the polyelectrolyte complexation between chitosan (CS) and gum arabic (GA) as novel delivery systems for curcumin. Optimization of parameters affecting the formulation of such nanocarriers was performed by means of dynamic light scattering and fluorescence analysis. It was demonstrated that at pH 4.0 and 1:1 mixing ratio of CS to GA, the two biopolymers can form hydrophilic, monodisperse and highly positively charged colloidal nanoparticles. Fourier-transform infrared and X-ray diffraction further confirmed their electrostatic interaction. Subsequently, the formulations and stability of nanoparticles loaded with curcumin were compared. The optimum formulation was found to be Tween 80/egg yolk phospholipid (1:1, w/w), curcumin/emulsifier (0.5:5, w/w) and curcumin concentration initially prepared (4%, w/w). The developed nanoparticles showed the average diameter in the range of 250–290 nm. The curcumin encapsulation efficiency and loading content respectively exceeded 90% and 3.8%, with a retention rate higher than 85% during storage. Additionally, whatever the antioxidant model was, the antioxidant activities of curcumin were significantly enhanced by nanoencapsulation. Furthermore, compared to emulsion without biopolymer coating, CS-GA nanoparticles can improve the stability and delay the release of curcumin in a simulated gastrointestinal environment. These findings suggested that CS-GA nanoparticles could be used as an ideal carrier to deliver hydrophobic bioactive ingredients like curcumin in functional foods.