A Review on Nanoemulsions: A Recent Drug Delivery Tool

Abstract

There is a growing interest for using of nano/sub-micron particles in the technology of pharmaceutical, cosmetic and also food. Especially, this interest has been increasing parallel with better emulsification techniques and stabilization mechanisms. There are two main groups of nanoemulsion preparation methods, namely high-energy and low-energy spontaneous emulsification methods. Preparation processes and components used are significant parameters that affect stability from few hours to years. Problems such as creaming, coalescence sedimentation and flocculation are not concern for nanoemulsions due to their small droplet size. However, the main destabilization mechanism is Ostwald ripening for them. In this paper, a comprehensive review is presented to give basic ideas about nanoemulsions, their preparation methods, and evaluations.

Keywords:  Nanoemulsion, preparation methods, evaluation