Although liposomes are often referred to as nanoparticles, they differ from classical nanoparticles in both, their structure and in their stability . Liposomes are therefore not nanoparticles in a narrower sense.
Nanoparticles are made of solid materials. Liposomes can be between a few nanometers to even 10 microns in size. They consist of certain lipids (so-called phospholipids, e.g from soy) together with other materials and form a hollow sphere consisting of one or more double membranes (bilayers – see Fig. 1, liposome with a double membrane). They are filled with water and require a water-loving environment. Their bilayers are water-loving on the outside and also inside of the hollow sphere. They are usually less stable than nanoparticles.
The encapsulation system “nanosome” is very similar to the liposomes. Nanosomes, however, possess only a single lipid monolayer. The name refers to their extremely small size. The name Nanosome is mainly used in cosmetics.