Liposome microencapsulations without using any organic solvent

Liposomes are microscopic vesicles composed of phospholipid bilayers surrou nding discrete aqueous compartment. Eventhough phospholipid bilayers are fo rmed spontaneously in water, their conventional preparation methods involve either organic solvents or detergent molecules. Organic solvents may creat e a serious safety problem during liposome manufacturing especially on a la rge scale and can cause denaturation of proteins and affect the membrane pr operties. Liposomes are very promising carriers for protein drugs which hav e aroused great interests in the field of pharmaceutics in these recent yea rs. The objective of this study was to develop a new dispersion process to prep are liposomes without the usage of organic solvents and detergents. The app roach involved the usage of a microfludizer for the extrusion and homogeniz ation of aqueous dispersion of phospholipids, and a modified evaporator in order to increase lipid thin film surface area. The properties of the lipos omes prepared by the novel method were superior to the liposomes prepared b y conventional methods.