Title : Preparation and characterization of Black Seed Oil loaded liposomes

Authors : Rushmi, Zerin, Akter, Nasrin, Mow, Rabeya, Afroz, Merina, Mirza, Sabiruddin, Mohammad Shariare

Abstract : Purpose Hydrophobic thymoquinone, principal bioactive constituent of black seed oil, possesses potential chemotherapeutic and antioxidant properties. Therefore, the aim of this study was to incorporate black seed oil as drug within the liposome for enhancing the bioavailability of thymoquinone. Methods Egg phospholipid, cholesterol and black seed oil were dissolved in ethanol by heating. This solution was then injected into phosphate buffer (pH 5.7) containing PEG6000 to produce liposomes. Inverse phase microscopy was used to observe particle size of liposomes. Particle size distribution of blank and encapsulated liposomes was determined by Malvern zetasizer. UV-Vis spectrophotometer at 255 nm was used for quantification of oil in the hydrophobic layers of the liposomes. Results Liposomes with or without encapsulated oil were prepared in the range of 50-520nm (Figure 1). Particle size distribution data (Figure 2) show that encapsulated liposomes were smaller in size (51.48±1.31nm) compared to blank liposomes (520.70±81.17nm). This is probably due to oil reduces the oxidation of phospholipids leading to less aggregation. Liposomal preparation, containing higher amount of black seed oil (1.3%v/v) demonstrate higher encapsulation efficiency of 57.60±0.53% compared to liposomal preparation containing less oil (0.33%v/v) showed encapsulation efficiency of 36.63±6.74%. Results suggest that increasing ratio of egg extract to cholesterol from 3:1 to 3:2 improves their encapsulation efficiency from 39.8% to 48.52%. This might be due to enhanced rigidity of lipid bilayer by increasing the amount of cholesterol. It has been also observed that application of heat during dissolving lipids attributed to enhanced oil entrapment. Result also indicated that 1ml/min injection rate and stirring rate of 2200 rpm gave less polydispersed liposomes compared to high injection (2ml/min) and stirring rates (>2500 rpm). This is possibly related to heterogenous nucleation and liposomal growth at high injection and stirring rates. Conclusion Though the purpose was to incorporate black seed oil as drug within the liposome, the oil being an antioxidant improved liposomal stability

Journal : Volume : Year : 2014 Issue :
Pages : City : Sandiego, USA Edition : Editors :
Publisher : AAPS annual meeting and exposition , 2014 ISBN : Book : Chapter :
Proceeding Title : American Association of Pharmaceutical scientists (AAPS) annual Meeting and Exposition, USA Institution : Issuer : Number :