Antioxidant loaded emulsions entrapped in liposomes produced using a supercritical assisted technique

Two different strategies for the encapsulation of hydrophobic bioactives within nanoliposomes were attempted. Three model lipophilic antioxidants (farnesol, limonene, linalool) were entrapped in liposomes using emulsions: drug was dissolved in the oil phase of an oil in water emulsion; then, the aqueous emulsion was entrapped in liposomes inner core using SuperLip (Supercritical assisted Liposome formation). Vesicles loaded with antioxidants in the lipidic layer, showed mean sizes from 116 +/- 32 nm to 230 +/- 62 nm, with an Encapsulation Efficiency (EE) up to 74% for farnesol, 87% for limonene and 54% for linalool. The use of 0/W emulsion, resulted in larger liposomes (among 397 +/- 103 nm and 605 +/- 175 nm), but also in an EE up to 99%. O/W emulsion method successfully preserved the antioxidant activity of the entrapped molecules. The reduction of the antioxidant power was about 22% for lipidic layer entrapment; whereas, only 2% using O/W method. (C) 2019 Elsevier B.V. All rights reserved.