Liposome-based drug delivery systems

Liposomes are spherical lipid bilayers from 50 nm to 1000 nm in diameter, and serve as a convenient delivery vehicle for biologically active molecules. Lipid/drug aggregates are easy to form and vulnerable to structural manipulations, allowing for the adjustment of their properties for particular purposes. In selected cases, the application of liposomes in pharmacological therapy improves drug pharmacokinetics compared to its free form. The major advantages of the liposome application are: the protection of active compounds from degradation; the increase in circulation time and the possibility to achieve partial or total selectivity. Selectivity alone improves drug potency, eliminates side effects and allows for dosage reduction. Selected liposome formulations are presented along with their present and potential applications. Also, the perspectives for further development of the technique are discussed.