Preparation Of Evening Primrose Oil Solid Lipid Nanoparticles

Objective:Evening Primrose Oil was prepared into SLN(solid lipid nanoparticles), and then determination method GC was established so as to conduct evaluation in vivo and vitro. Nanoparticles were prepared into lyophilized powder. At last, trials were carried out to see the inflammation and hypolipidemic action of SLN on mice. Methods:1.The main factors that influence the quality of SLN were filtered by means of microemulsion, by evaluation index of nanoparticles’ encapsulation efficiency, by variety and dosage of single factor test of emulsifier, the proportion of emulsifier and auxiliary emulsifier, the dosage of lipid material, and the dosage effect of evening primrose oil on SLN entrapment efficiency. And on this basis orthogonal design method was applied to optimize prescriptions in accordance with the mass ratio of evening primrose oil consumption and glyceryl monostearate, the mass ratio of evening primrose oil consumption and mixed emulsifiers, and the evaluation index of SLN entrapment efficiency.2.The quality appraisal of SLN was carried on through laser Particle Sizer, transmission electron microscope, gas chromatograph, together with content determination and stability, and release rule in vitro were evaluated simultaneously.3.Freeze-drying method was adopted to dry SLN dispersion liquid into solid power, and then evaluation was carried on to check the quality of SLN after drying.4.The experiment that Xylene was used to induce mouse ear swelling was used to see the anti-inflammatory effect of evening primrose oil SLN and the text of the influence on plasma lipid level of mice with hyperlipidemia was adopted to investigate the antihyperlipidemic effect of evening primrose oil SLN.Results:The optimal preparation technology of evening primrose oil SLN was: 300mg evening primrose oil, the mass ratio of glyceryl monostearate and evening primrose oil was 2:3, the mass ratio of evening primrose oil and emulsifier was 1:2(Cermophor RH-40/PEG-400), the mass ratio of Cermophor RH-40 and PEG-400 was 1:2. Prepared SLN was translucent solution with obvious light blue opalescence. And SLN under transmission electron microscopy looked similar to the round; Average particle size was 44.43±0.08 nn. Zeta potential was 64.72±1.24 mV. Average embedding ratio was 89.33±0.82%. Average content of γ-linolenic acid in 3 batches of evening primrose oil SLN was 0.728±0.004%. Stability test shows that SLN is more stable in 4℃ storage range. Freeze-drying method is:2 mL SLN with 4% PEG-6000,12 h pre-freezing,24 h freeze-drying in -60℃. The animal experiments prove that evening primrose oil SLN has anti-inflammatory action, obviously reducing TC, TG of mice with acute hyperlipidemia, and enhance HDL-C. Evening primrose oil SLN also treats acute hyperlipidemia and works better than evening primrose oil soft.Conclusion:The preparation of evening primrose oil SLN was simple, together with good quality and stable physical and chemical properties. The animal experiments prove that evening primrose oil SLN has anti-inflammatory and anti-hyperlipidemia action.