Preparation and Characterization of Solid Lipid Nanoparticles Containing Zataria multiflora Boiss Essential Oil by High-shear Homogenization and Ultrasound Method

One of the new methods to overcome problems with using essential oils (such as instability, evaporation and decomposition in the environmental conditions) in pharmaceutical, food and agricultural industries is use of Solid Lipid Nanoparticles (SLNs) carrier systems.
Preparation of SLNs containing the Zataria multiflora Boiss essential oil.
In this regard, an experiment was performed on the preparation of SLNs containing the Zataria multiflora Boiss essential oil at Nanotechnology Research Center of School of Pharmacy, Mashhad University of Medical Sciences. SLNs containing Zataria multiflora Boiss essential oil was prepared using high tensile pressure homogenization and ultrasound. Components of SLNs include lipids, Zataria multiflora Boiss essential in fat phase and poloxamers 188 in the aqueous phase. The mean particle size and zeta potential, essential oil encapsulation percentage and thermal analysis were measured using particle size analysis instruments, gas chromatography and differential scanning calorimetry (DSC), respectively. Moreover, an electron microscope was used for imaging of SLNs.
The results showed that particle size, polydispersity index and zeta potential of the above formulations were respectively about 486 nm, 0.296, -27.2 mv. The results obtained from transmission electron microscopy (TEM) showed particle size less than 300 nm and particles were spherical. Thermal analysis by DSC, confirmed the presence of solid particles in the prepared SLN. Also, the essential oil encapsulation percentage was 95.2 percent. Stability studies of particle size and zeta in four months showed SLNs containing essential oils had relatively good stability.
In general, the results of the present research showed that SLNs composed of stearic acid, was good carriers for Zataria multiflora Boiss essential oil.