Preparation Of The Lutein Solid Dispersions

Objective:Prepared Lutein solid dispersions (SD) by spray drying method, to improve water-soluble difference, low dissolution rate of Lutein. And the stability of Lutein solid dispersions was also studied.Methods:(1) Study the physicochemical proterties of Lutein, such as solubility, oil-water partition coefficient, the stability of solid material and solution, etc. Content determination method of Lutein and the dissolution in vitro was established.(2) Lutein solid dispersions were prepared using spray drying method. As the index of cumulative dissolution curve in60min, single factor investigations were established to optimize the preparing technology of solid dispersion. The prescription was excellently screened with L9(34) orthogonal design, and three influencing factors such as ethanol concentration, spray solid content, the weight ratio of the drug and carrier were selected.(3) Evaluate the quality of Lutein solid dispersions prepared by optimal prescription.(4) The stability test was carried out for Lutein solid dispersion through the influence factors and long-term experiment, in order to study the storage conditions of Lutein solid dispersions.Result:(1) Master the physicochemical properties of the Lutein material, and establish a set of feasible content determination method based on its ultraviolet absorption characteristics. The results of verified methodology conformed that the analysis method met the requirements. Lutein was almost insoluble or insoluble in water, and was fatty substance. It was not stability in the artificial gastric juice pH=1.2and in the simulated intestinal fluid pH=6.8. But it has higher stability in aqueous solution. The conditions of light, air and temperature were made more influence on the stability of Lutein solid, and when long placed in air Lutein solid was easily oxidized.(2) The optimal prescription of preparing Lutein solid dispersion which was obtained by orthogonal experiment was that the proportion of Lutein and accessories was1:25, the auxiliary materials which contained A and B, the weight ratio was1:1.5. And the anhydrous ethanol for dispersion solvent, spray solid content was30%. Orthogonal experiment validation showed that the best prescription was stability, and repeatability was well.(3) Using four types of phase identification methods to evaluate solid dispersions, they were concluded that Lutein was in amorphous state in solid dispersions, and formed a eutectic mixture. Dissolution determination results showed that under different methods of dissolution, release behavior of Lutein solid dispersions was different. But the impact of dissolution speed was little to the solid dispersions. Comparing the cumulative dissolution in vitro of Lutein, physical mixture and solid dispersion, it showed that Lutein solid dispersion was more significantly increased the solubility and dissolution rate than Lutein and physical mixture.(4) Through the study to the stability of Lutein solid dispersions, it showed that they were higher stability than raw materials in strong light (4500Lx±500Lx) and high temperature (50℃). But Lutein solid dispersions were poor stability in high humidity (RH75%). And under room temperature(25±2℃) of airtight preservation for three months, Lutein solid dispersion stability was well.Conclusion:By using a mixture carrier of A and B prepared by spray drying method, Lutein solid dispersion can significantly improve the solubility and dissolution rate of Lutein, and increase its stability. But Lutein solid dispersion was easy absorption of moisture, it should be maintained in a dry place after the seal.