Impact of different extraction methodologies on the physical, structural and thermal properties of lecithin-sesame oil-based nanoliposomes containing citron peel essential oils

For the first time, a comparative study was conducted on the physical, structural, thermal properties and release behavior of nanoliposomes loaded with different essential oils of the citron peel obtained by hydrodistillation and supercritical fluid extraction methods. These nanovesicles were prepared using a new formulation based on the combination of lecithin and sesame oil with different concentrations (40:60, 50:50 and 60:40 w/w%). The encapsulation efficiency and particle distribution index for the prepared nanoliposomes were in the range of 63–71% and 0.175–0.231. As the lecithin concentration increased, encapsulation efficiency increased while the particle distribution index decreased. The spherical shape of nanoliposomes containing different essential oils, the presence of interaction between both types of essential oils and nanoliposomes, and increasing the thermal stability of two essential oils after encapsulation were observed by SEM, FTIR and DSC tests, respectively. Nanoliposomes containing supercritical fluid essential oil in vitro had a lower release percentage (14.08–40.1%) than the hydrodistillation essential oil samples (16.06–41.07%) with the same formulation. It suggests that supercritical fluid extraction may enhance sustained release properties.