Spread Lipid Films on Liquid Surfaces (Langmuir–Blodgett Films) - Surface and Colloid Chemistry: Principles and Applications - page 102

Micelle
Monolayer
L-B Film
Ve sicle
FIGure 4.13 Different self-assembly (SA) structures: (a) micelle; (b) monolayer; (c) LB
film; (d) vesicle; (e) liposome.
pure surfactant components such as DOPE (dioleolylphosphatidylethanolamine).
Liposomes usually contain a core of aqueous solution. Vesicles are unilamellar
phospholipid liposome.
The word liposome comprises two terms (from Greek— lipid [fat] and soma
[body]). It does not in itself denote any size characteristics. Furthermore, the term
liposome does not necessarily mean that it must contain lipophobic contents, such
as water, although it usually does. The vesicles may be conceived as microscopic
(or nano-sized ) containers of carrying molecules (drugs) from one place to another.
The structures are suitable for both transporting water-soluble or water-insoluble
drugs. Since the lipids used are biocompatible molecules, this may also enhance
their adsorption and penetration into the cells.
During the past decades, liposomes have been used for drug delivery on account of
their unique solubilization characteristics for water-insoluble organic substances. A
liposome encapsulates a region of aqueous solution inside a hydrophobic membrane;
dissolved hydrophilic solutes cannot readily pass through the lipids. Hydrophobic
chemicals can be dissolved into the membrane, and this way, the liposome can carry