How does a liposome form?

Liposomes can form naturally when tissues are disrupted. It starts with fragments of the cell membrane getting detached when tissue is damaged. These exposed lipid bilayer fragments then fold back on themselves. As they do this, they capture and surround a small packet of the contiguous solution. This occurs due to the interactions between the hydrophobic (water-repelling) and hydrophilic (water-attracting) parts of the lipid bilayer and the aqueous environment. The hydrophobic ends come together to form a sealed internal pouch called the liposome. 

The natural process of liposome creation can be replicated in the lab using a sonic wave generator. In this laboratory technique, sonic waves are used to break apart lipid bilayer membranes into various-sized liposomes. The energy from the sonic waves separates the bilayer molecules into pieces, which then fold into liposomes due to the same forces that drive their natural formation.