ABSTRACT
This chapter discusses various aspects of nanoparticulate systems in the context of drug delivery. Lipophilic drugs can be codissolved with the lipids during liposome preparation. Hydrophilic drugs can be passively entrapped into liposomes during liposome formation. The application of liposomes as a drug-delivery system has become more popular, because of their biocompatibility and versatility in carrying systemically administered drugs such as chemotherapeutics and antibiotics with narrow therapeutic windows. Liposomal delivery of anticancer drugs has been shown to greatly extend their systemic circulation time, reduce toxicity by lowering plasma free drug concentration, and facilitate preferential localization of drugs in solid tumors based on increased endothelial permeability and reduced lymphatic drainage, or enhanced permeability and retention effect. Although high stability of liposomes prior to reaching the cellular target is generally desirable, efficient release of liposomal drug in the target tissue and/or cell is essential for its therapeutic activity.
