Phospholipids are indispensable for the live organism and play an essential role for both health and nutrition due to a great variety of different functions. They are used, technically as surface-active compounds, but also as cosmetic actives and modulator of skin penetration. Saturated phospholipids are used as surface-active compounds and unsaturated phospholipids are suitable to enhance skin penetration. The relation of phospholipids to nanotechnology is apparent when they are, e.g., used as an emulsifier in “nano-emulsions” and as component of “nano-liposomes”, having particle sizes in the nano-range.
https://link.springer.com/chapter/10.1007/978-3-030-16573-4_6