Characterization and stability evaluation of olive oil nanoemulsion-based hydrogel formulation by nanophase emulsification technique

The purpose of this study was to construct a stability study of nanoemulsion-based hydrogel formulation and evaluate the profile of the formulation that exhibits the best stability. Olive oil was chosen as oil phase of nanoemulsion due to its superiority as an emollient and it has good skin permeation capability. In this study, a series of nanoemulsion formulation was prepared based on the various oil/surfactant ratio and carbopol concentration. Their stability in three months storage at room temperature was evaluated by comparing mean droplet size, polydispersity index (PDI), zeta potential and rheology of nanoemulsion hydrogel. Based on the characterization of three months physical stability study, nanoemulsion-based hydrogel with 20% olive oil and oil: surfactant ratio of 5:1 was more stable compared to other formulations in terms of droplet size properties and rheological behavior.