Hydroxypropyl-β-cyclodextrin as a membrane protectant during freeze-drying of hydrogenated and non-hydrogenated liposomes and molecule-in-cyclodextrin-in- liposomes: Application to trans-anethole

摘要

The effect of hydrogenation of phospholipids on the characteristics of freeze-dried liposomes was investigated using hydroxypropyl-beta-cyclodextrin (HP-beta-CD) as membrane protectant. The ethanol-injection method was applied to prepare liposomes using hydrogenated (Phospholopion-90H and 80H) and non-hydrogenated phospholipids (Lipoid-S100) in combination with cholesterol. Various liposomal formulations were tested: conventional liposomes (CL) and HP-beta-CD-loaded liposomes (CDL). Liposome suspensions were concentrated by ultracentrifugation; the pellets were reconstituted in water or CD solution and the dispersions were characterized for their size, polydispersity index and zeta potential. Results demonstrated that HP-beta-CD protected only the hydrogenated batches (CL and CDL) during freeze-drying. Moreover, the presence of HP-beta-CD in the aqueous phase of CDL protected them during freeze-drying. Freeze-dried CL and CDL made of phospholipon-90H loading anethole were demonstrated to be physically stable upon reconstitution in HP-beta-CD solutions, and are able to retain anethole after 6 months of storage at 4 degrees C thereby making them valuable for food applications.