Functional nanoemulsions: Controllable low-energy nanoemulsification and advanced biomedical application

Nanoemulsions are widely used as advanced pharmaceutical delivery systems in biomedical field, due to their high encapsulation efficiency and good therapy efficacy.Nanoemulsification techniques that produce nanoemulsions with controllable sizes and compositions are promising for creating advanced nanoemulsion systems for pharmaceutical delivery.This review summarizes recent advances on low-energy emulsification techniques for producing nanoemulsions, and the use of these nanoemulsions as advanced pharmaceutical delivery systems and as templates to create drug-loaded functional particles for biomedical application.First, nanoemulsification techniques that utilize elaborate interfacial physics/chemistry and micro-/nano-fluidics, featured with relatively-low energy input, to produce nanoemulsions with controllable sizes and compositions, are introduced.Uses of these nanoemulsions to create nanoemulsionincorporated milli-particles, drug-loaded nanoparticles and nanoparticle-incorporated microparticles with sizes ranging from several millimeters to sub-10 nm are emphasized.Flexible and efficient use of the nanoemulsions, functional nanoparticles and milli-/micro-particles integrated with nanoemulsions or nanoparticles for advanced pharmaceutical delivery in biomedical field are highlighted, with focus on how the interplay between their sizes and compositions achieve desired pharmaceutical-delivery performances.Finally, perspectives on further advances on the controllable production of nanoemulsions are provided.