Aggregation of phospholipid self-assembled structures with addition of cholesterol and curcumin based on coarse-grained molecular dynamics simulations.

Phospholipids as the main constituent of the living cell membrane can form self-assembled structures called liposomes in the aqueous milieu. They are drug delivery systems with high biocompatibility. With the addition of cholesterol, liposomes are effective for encapsulating low bioavailability and stability drugs such as curcumin. This study uses coarse-grained molecular dynamics simulation of several phospholipid species with cholesterol and curcumin to determine the formation of a self-assembled structure. The result shows that there are 4 self-assembled structures namely liposome, disc-like micelle, cylindrical micelle, and planar bilayer along with a rapid decline in total energy. Liposome owned the highest total energy followed by disc-like micelle, cylindrical micelle, and planar bilayer as the lowest. Increased concentration of cholesterol will increase the possibility of liposome forming, the total energy of the system, liposome stability, liposome lifetime, liposome membrane thickness, and the size of liposome, but will decrease the area per lipid of liposome membrane. The influence is also exerted by the nature of phospholipid species itself such as the type of head group, length of hydrocarbon tail, and the number of double bonds on the hydrocarbon tail. Curcumin encapsulated in the liposome bilayer causes an increase in the total energy of the system and the size of the liposome. [ABSTRACT FROM AUTHOR]