Stability of Liposomal Formulations in Physiological Conditions for Oral Drug Delivery

Abstract

The stability of liposomal formulations is a key issue in drug delivery. Liposomes made of egg phosphatidylcholine (EPC), cholesterol (Chol), sphingomyelin (SM), and gangliosides (GM1 and GM type III) were incubated in different media to determine their stability. Mixtures containing GM1 or GM type III were found to be the most stable, and both showed similar stability trends in plasma at 37 degrees C. EPC/Chol was the most susceptible to lysis in plasma. In acid media (pH 2), the highest stability corresponded to EPC/Chol, whereas in bile and pancreatin, liposomes with GM1 and GM type III were more stable than those containing SM. This study suggests that among the formulations used as oral drug carriers, those containing GM1 and GM type III have higher possibilities of surviving through the gastrointestinal tract.

Stability of liposomes containing bio-enhancers and tetraether lipids in simulated gastro-intestinal fluids

“…Taira et al (2004) found a CF release from conventional EPC/Chol liposomes in pancreatin of around 10% after 90 min, which is in good agreement with our results. The somewhat higher leakage of the EPC/GCTE/Chol formulation might be related not only to an enzymatic degradation of the lipids but also to protein/membrane interaction causing a destabilisation of the liposomal membrane (see Fig.…”

“…This was already found in previous studies, where liposomes stayed intact at low pH and leakage of macro- Values represent mean ± SEM with n = 4 (A and B) or n = 3 (C and D). Groups with and without GCTE in graph D were compared by one-way Student's t-test with *p < 0.05, p < 0.01, ***p < 0.001. molecules was not very pronounced (Patel et al, 2000;Taira et al, 2004). TELs are known to increase the stability of membranes at low pH, but the EPC/GCTE/Chol formulation showed the highest instability under those conditions and this effect was reduced by the addition of the two surfactant bio-enhancers TPGS and CS (Elferink et al, 1994).…”

“…Liposomes made with phospholipids with a glass transition above body temperature or containing other stabilising lipids like gangliosides can survive the gastro-intestinal tract (Muramatsu et al, 1996;Han et al, 1997;Taira et al, 2004). Since their first description by Langworthy in 1977 naturally derived tetraether lipids (TELs) were used in liposomes to improve their stability and also their immunogenicity for vaccine delivery (Langworthy, 1977;Choquet et al, 1994;Fan et al, 1995;Komatsu and Chong, 1998;Patel and Chen, 2005).…”

Engineering Polysaccharide-Based Polymeric Micelles to Enhance Permeability of Cyclosporin A Across Caco-2 Cells

“…Alternative approaches investigated include incorporation of the drug within microspheres, nanoparticles, and liposomes (12)(13)(14)(15)(16). Given the limited stability of liposomes in vivo, they have not been widely applied in clinical use (17)(18)(19). Other particulate vehicles, however, have been developed and show promising properties in terms of controlled drug release and distribution (20)(21)(22)(23).…”

Characterization of Antimicrobial-bearing Liposomes by ζ-Potential, Vesicle Size, and Encapsulation Efficiency

“…1,2 Liposome entrapment may stabilize encapsulated bioactive materials against a range of environmental and chemical stresses, including presence of enzymes or reactive chemicals and exposure to extreme pH, temperature, and high ion concentrations. [3][4][5] The functional properties of liposomes depend on their size, composition, and stability in food systems. 6 Liposomes are typically spherical in shape and may consist of single or multiple bilayers composed of polar lipids.…”