Effect of preparation methods on the properties of Zataria Multiflora Boiss. essential oil loaded nanoliposomes: characterization of size, encapsulation efficiency and stability

Background: essential oil (eo) of zataria multiflora bioss., contains componentswith antibacterial and antifungal properties that can be used as substitutes for syntheticdrugs and food preservatives. these applications require appropriate carriers likenanoliposome. the purpose of this study was to encapsulate this eo intonanoliposomes. in addition, the effects of preparation methods were evaluated on thephysical properties of nanoliposomes. methods: the eo was encapsulated intonanoliposomes by three different methods including thin film evaporation, ethanolinjection and sonication methods. formation of liposomes and their physicalproperties was studied by means of particle size, polydispersity index, zeta potentialand encapsulation efficiency. in addition the changes in eo retention and mean sizedistribution were studied during one month of storage at 4±1°c. results: liposomalsystems prepared by sonication method with about 99 nm displayed the smallest meansize and better dispersivity. the encapsulation efficiency of nanoliposomes containingeo was in the following rank order: thin film evaporation > ethanol injection > sonication. moreover, mlv (multilamellar vesicles) liposomes prepared by the thinlayer evaporation method showed better stability during storage. conclusions: thisstudy indicated that the preparation method can affect the formation of liposomes andtheir physical properties and storage stability.