Development of polyglycerol fatty acid ester-based low-energy nanoemulsion for the improvement of curcumin stability

Three kinds of polyglycerol fatty acid esters were used as emulsifiers to produce curcumin-loaded nanoemulsions by low-energy emulsification. Characterization of nanoemulsions was performed by measuring the droplet size, polydispersity index, and zeta potential. The morphology of the curcumin-loaded nanoemulsions was observed by transmission electron microscopy. The mean droplet size ranged from 19.6 ± 0.3 nm to 76.2 ± 2.3 nm, and the polydispersity index was less than 0.15 in all conditions. Physical stability was observed by multiple light scattering and dynamic light scattering methods, and polyglycerol fatty acid ester-based nanoemulsions were found to be remarkably stable for 60 days. After 60 days, 78.9–86.1% of the initial total amount of curcumin was still preserved in the nanoemulsions, which is a promising result when compared with those of other nano-encapsulation systems.