Liposome formation by adipose tissue derived lipids and its applications

Abstract

A liposome is an artificially-prepared vesicle composed of a lipid bilayer. This project aims to produce liposomes using human adipose tissue derived lipids (ATDL). Furthermore, the study attempts to find the alternative use of discarded human adipose tissue after the liposuction operation. Conventionally prepared liposomes are usually made up of phosphatidylcholine and cholesterol, two major constituents of cell membrane. The presence of other phospholipids like phosphatidylserine, phosphatidylinositol, phosphatidylethonolamine and sphingophospholipids of the cells and organelles membranes may mimic the natural cell membrane and stabilise the liposomes further and increase its efficiency as intracellular drug delivery vehicle. These other useful phospholipids could be extracted from the discarded adipose tissues. The lipids were separated from the human adipose tissue by Folch Method and characterised using FTIR. Thin film hydration method was adapted to produce liposomes with 2 different sources, lecithin- cholesterol and ATDL. The liposomes were analysed under light microscope and characterised using DLS. Then these liposomes were loaded with trehalose, a known disaccharide and cryoprotectant. Moreover, the drug encapsulation efficiency and effect of trehalose loaded liposomes on the cryopreservation of red blood cells were compared between conventional and the proposed method. The liposomes made up of ATDL are smaller in size and have less encapsulation efficiency as compared to conventional liposomes. The conventionally produced liposomes loaded with trehalose have very high cryoprotective properties (as much 85% RBCs were alive) but at the same time the cryoprotective properties of ATDL liposomes loaded with trehalose is also quite significant (approximately 70% RBCs are alive).The lower cryoprotective ability of the ATDL liposomes may be due to the lower encapsulation efficiency of it for the water soluble drugs such as trehalose.