A Simple Method for the Preparation of Liposomes for Pharmaceutical Applications: Characterization of the Liposomes

Abstract

A new method for the preparation of liposomes is described that avoids the use of pharmaceutically unacceptable solvents and energy-expensive procedures such as sonication. The method is based on the initial formation of a proliposome mixture containing lipid, ethanol and water, which is converted to lipsomes by a simple dilution step. Measurements using 6-carboxyfluorescein as a marker indicate that water-soluble drugs can be trapped with extremely high efficiency (65-80% depending on lipid composition). The structural organization of the proliposome mixture and the final liposomes were characterized using electron microscopy and 31P-NMR.

Proultraflexible lipid vesicles for effective transdermal delivery of levonorgestrel: Development, characterization, and performance evaluation

“…PTG was prepared by the method reported by Perrett et al 15 for the preparation of proliposomes. Phospholipid, surfactant, alcohol, and drug were taken in a small, clean, dry, wide-mouth glass tube.…”

Application of Liposomes for Construction of Vaccines

“…To classify these methods, they were arranged in three categories: 1) mechanical dispersion methods such as hand shaking or vortexing, sonication, and high pressure homogenisation; 2) detergent-solubilizing dispersion methods including solubilized lecithin dispersion with sodium cholate or octylglucoside; and 3) solvent dispersion methods such as ethanol injection, ether infusion, and reverse-phase evaporation. These primary processes can be linked with secondary processes such as high-pressure homogenisation or extrusion through polycarbonate filters of various pore size, which are easy ways to prepare liposomes of a desired size and morphology (Barnadas-Rodriguez & Sabes, 2001;Berger et al, 2001;Cullis, 1987;Hope et al, 1985;Perrett et al, 1991;Turanek, 1994;Woodle & Papahadjopoulos, 1988;Schneider et al, 1995). The stability of proteins is limited and not all the methods are useful for the preparation of proteoliposomes, especially if the protein is to be entrapped inside the liposome.…”

An Ethanol-Based Proliposome Technology for Enhanced Delivery and Improved “Respirability” of Antiasthma Aerosols Generated Using a Micropump Vibrating-Mesh Nebulizer

“…Proliposome technologies are economical alternatives to freeze-drying. For instance, ethanol-based proliposomes are concentrated ethanolic solutions of phospholipid which generate liposomes by addition of aqueous phase and shaking (Perrett et al, 1991). The suitability of ethanol-based proliposomes to generate inhalable liposomes via nebulizers has been demonstrated (Elhissi et al, 2006;Elhissi et al, 20011).…”