Nanoemulsions for drug delivery

Emulsions are liquid-liquid dispersions with one liquid phase dispersed in the other liquid phase as small droplets. Nanoemulsions are nano-sized emulsions with sizes ranging from tens to hundreds of nanometers, and have great potential applications in pharmaceutics, foods and cosmetics due to their attractive properties, such as small sizes, high surface area per unit volume, improved dispersion of active hydrophobic components and enhanced absorption. The article provides an overview of nanoemulsions for drug delivery, starting with an introduction of emulsion types, nanoemulsion preparation and nanoemulsion stability. Surfactants play critical roles in producing and stabilizing nanoemulsions. Different types of surfactants are summarized including small molecule surfactants, particle surfactants, phospholipids, peptide and protein surfactants. Then the applications of nanoemulsions as nanomedicine in drug delivery are presented. Finally, clinical applications of nanoemulsions are discussed. (c) 2021 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

Emulsions are liquid-liquid dispersions with one liquid phase dispersed in the other phase as small droplets. Nanoemulsions, with sizes ranging from tens to hundreds of nanometers, hold great potential in pharmaceutics, foods, and cosmetics due to their small sizes, high surface area, improved dispersion, and enhanced absorption. Surfactants are crucial in producing and stabilizing nanoemulsions, including small molecule surfactants, particle surfactants, phospholipids, peptides, and protein surfactants, which play different roles in drug delivery applications.