CARNOSINE-CONTAINING LIPOSOMES: PREPARATION AND PROPERTIES

Abstract

Carnosine is a natural dipeptide antioxidant. It is proved that it protects human’s cells from oxidative stress. However, it has a short lifetime in a human organism due to the carnosinase activity. In order to solve this problem we used carnosine encapsulated in liposomes. Thus, the aim of this study was the creation of a new liposomal carnosine drug form. We used two encapsulation methods that show different carnosine behavior: a passive and an active one. We took into account that conditions of obtaining liposomes such as lipid composition, pH and temperature are important. In this study the lipid composition providing the maximum encapsulation efficiency was determined. Dipalmitoylphosphotidylcholine (DPPC) and its mixture with cholesterol (Chol) wereused as composition lipids. It was shown that the active encapsulation method using the creation of ammonium sulphate pH gradient provided the best results: 41.7% encapsulation efficiency (according to NMR spectroscopy) when using DPPC:Chol (7:3) mixture as lipids. Moreover, the properties of the liposomes were studied. Using the dynamic light scattering and electron microscopy methods carnosine liposomes (DPPC:Chol) were shown to be spherical nanoparticles with an average size of 133 nm. Carnosine release kinetics studied with the use of a France’s cell showed that carnosine was released in 24 hours (liposomal composition DPPC:Chol was 7:3). A study of carnosinase action on liposomal carnosine showed that the maximum amount of carnosine remained unchanged in DPPC:Chol liposomes (7:3). The results of the study make it possible to conclude that liposomal carnosine has a better activity in the human organism.

Keywords

• carnosine
• liposomes
• dipalmitoylphospotidylcholine
• active carnosine encapsulation method
• carnosinase