Recent Trends in Liposomes Used As Novel Drug Delivery System
Journal: The Pharma Innovation
Volume: 1
Issue: 1
Volume: 1
Issue: 1
Author: K.P. Sampath Kumar*, Debjit Bhowmik and Lokesh Deb
Abstract: Drug delivery systems have become important tools for the specific delivery of a large number of drug molecules. Since their discovery in the liposomes were recognized as models to study biological membranes and as versatile DDS of both hydrophilic and lipophilic molecules. Liposomes are artificially prepared vesicles made of lipid bilayer. Liposomes can be filled with drugs, and used to deliver drugs for cancer and other diseases. Liposomes are composite structures made of phospholipids and may contain small amounts of other molecules. Though liposomes can vary in size from low micrometer range to tens of micrometers, unilamellar liposomes, as pictured here, are typically in the lower size range with various targeting ligands attached to their surface allowing for their surface-attachment and accumulation in pathological areas for treatment of disease. Liposomes are used as models for artificial cells. Liposomes can also be designed to deliver drugs in other ways. Liposomes that contain low (or high) pH can be constructed such that dissolved aqueous drugs will be charged in solution. Liposomes are artificial vesicles comprised of lipid and aqueous compartments where the lipid exists in the bilayer form. Such vesicles can be composed solely of phospholipids or in combination with other amphipathic molecules such as sterols, long chain organic bases or acids. When phospholipids are suspended in an excess of aqueous solution they spontaneously form multilamellar concentric bilayers with lipid layers separated by layers of aqueous medium. Water soluble substances such as drugs, proteins, nucleic acids and dyes, present in the aqueous phase during the formation of liposomes, can be encapsulated into the aqueous compartments of the vesicles. This unique property of liposomes has made them a versatile tool for an increasing number of studies in biology and medicine.
Keyword: Liposome, Targeting cancer, Vesicle, artificial cells.