The influence of membrane composition on the release of polyphenols from liposomes

Abstract

Polyphenols are compound which are widely studied because of their antioxidative and potential therapeutic properties. Systems for the controlled release of drugs offer a number of benefits comparing with traditional forms of medicines and because of that these systems are widely researched. The objective of this paper is to investigate the possibility of using liposomes as carriers of polyphenols and influence the membrane composition on the release rate of encapsulated polyphenols. Experiments show how the membrane modification affects the mass transfer comparing to a conventional liposomes. Liposomes were modified with surfactants Tween 20 and Tween 60, and thyme tea extract was used as a source of polyphenols. The diffusion of polyphenols from thyme extract, dispersion of conventional liposomes and liposomes modified with Tween 20 and Tween 60 was studied using Franz diffusion cell. From the experimental data diffusion coefficients were determined for each of the systems, as well as the corresponding diffusion resistances. From the obtained results it can be concluded that the encapsulation of polyphenols in liposomes significantly slows diffusion, and with membrane modification can be achieved further slowing. The diffusion resistance of the liposome membrane modified with Tween 20 and Tween 60 is about 5 times higher compared to the diffusion of unencapsulated polyphenols from the thyme extract.

Keywords

• diffusion coefficient
• diffusion resistance
• liposomes
• membrane modification
• polysorbate
• tea polyphenols