Formulation and characterization of liposomes

Liposomes are vesicular structures composed of one or more concentric lipid bilayers surrounding an aqueous cavity. They are gaining significant consideration in pharmaceutical, cosmeceutical, as well as food applications due to their unique properties, such as biocompatibility, biodegradability, flexibility for surface modification, versatility in encapsulating a wide range of bioactive molecules and releasing them in a particular fashion as desired and, moreover, ease of preparation and scale up. This chapter begins with a discussion of the mechanism of liposome formation followed by liposomal formulation by conventional methods with their features and complications, novel formulations along with their pros and cons, utility, and possibility to scale up. The chapter also discusses various physicochemical characterizations to assess the quality of liposomes. In addition, the spotlight is also put on the in vivo fate of liposomes after oral administration.