Preparation, Optimization and characterization of α-Tocopherol-loaded Solid Lipid Nanoparticles (SLNs).

The main scope of present investigation was preparation and Physicochemical characterization of solid lipid nanoparticles (SLNs) loaded by α-Tocopherol acetate (ATA). ATA-loaded nanoparticles were prepared by solvent injection-homogenization technique using stearic acid as the solid lipid, phosphatidylcholine as the stabilizer and finally coated by chitosan with the aim of increasing z-potential and also having a more stable nano-formulation. Then, characterization of SLNs has been conducted using dynamic light scattering (DLS), zeta potential measurement, fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC). Nanoparticles with average sizes of 175 ± 15 nm and zeta potential of +35 ± 2.5 mV were obtained. An excellent drug entrapment efficiency of 90.58 ± 1.38% was obtained with a no-burst slow release up to about 10 days tested. The final plateau of release of alpha tocopherol acetate from nanoparticulate system within 216 hours was 61.13 ± 0.13% which was approached in about 150 hrs. Physical stability studies showed that the ATA nano-formulation remained stable with slight increase in mean particle size and polydispersity index over a 3-month period in refrigerated temperature. Considering both FTIR and DSC analysis, it can be concluded that there is no new band formation between materials and ATA in our nano-formulation. Particle sizes obtained using AFM images are in a good agreement to those established from the DLS analysis. These data showed a promising delivery system for vitamin E based on SLN platform.