Layer-by-layer coated emulsion microparticles as storage and delivery tool

Microencapsulation is an imperative technology in pharmacy, food industry and medicine. However, the current level of the development requires not only the fabrication of the emulsion systems, but also their functionalization in order to impart it multifunctional properties. One of the most perspective approaches to attain additional functionality to the emulsion particles is the use of the layer-by-layer modification of their surface. This technique permits the step-wise adsorption of various components (polyelectrolytes, nanoparticles, proteins, enzymes, etc.) as the layer growth is governed by their electrostatic, hydrogen bonding, hydrophobic, etc. forces and allows the formation of multilayer shells with nanometer (thickness) precision. The proposed review surveys the layer-by-layer approach for modification of both polymer and Pickering emulsions with polyelectrolyte or nanoparticle multilayers together with the demonstration of the application examples of the modified emulsion systems, where the emulsion particles play simultaneously the role of the template for layer-by-layer assembly as well as of the inner load.