Preparation and characterization of oleanolic acid-loaded solid lipid nanoparticles for oral administration

Oleanolic acid-loaded solid lipid nanoparticles（OA-SLNs）were prepared by using an improved emulsion-solvent evaporation method.The size,zeta potential,encapsulation efficiency,and loading efficiency of OA-SLNs were（104.5±11.7）nm, （-25.5±1.8）mV,（94.2±3.9）%,and（4.71±0.15）%,respectively.The morphology was illustrated by TEM as sphere stuffed particles.The XRD and DSC spectra confirmed that the OA molecules were dispersed uniformly into SLN matrixes.The results of in vitro release test suggested that OA was released slowly at a rate of 4.88%per hour from SLN preparation,which was consistent with the Zero-order Released Model.In addition,OA-SLNs were stable in artificial gastric juice and artificial intestinal juice.Together,our results provided new data for the potential application of OA-SLNs in oral administration.

Preparation and characterization of budesonide-loaded solid lipid nanoparticles for pulmonary delivery

To increase the solubility and adsorption of budesonide（BUD）,budesonide-loaded solid lipid nanoparticles（BUD-SLNs） were prepared and characterized in this study.Glycerin monostearate（GMS）was selected to be the matrix lipid material after calculation the differences of partial solubility parameters.An emulsification-ultrasound diffusion method was employed and formula was optimized in the BUD-SLNs preparation.The entrapment efficiency（ee%）of BUD-SLNs was（97.77±2.60）%, and the mean particle size was 147.3 nm（PDI=0.228）.Uniform and sphere particles were observed under TEM.The in vitro release of BUD-SLNs could be well explained by the biphasic release dynamics equation.The spectrums of DSC and X-ray diffraction indicated that BUD molecules were dispersed mainly into the lipids to form homogeneous matrix structure.Our results provide fundamental data for the application of SLNs in pulmonary delivery system.