姜黄素立方液晶制备工艺过程中的光稳定性研究

Study on the photostability of curcumin cubic liquid crystals in the preparation process

目的采用高效液相色谱法对姜黄素和姜黄素立方液晶的光稳定性进行考察,研究水、乙醇及pH等对姜黄素光稳定性的影响。方法将不同处方项下的姜黄素立方液晶于不同光照条件下放置,并以HPLC-UV法测定姜黄素含量;通过比较姜黄素立方液晶溶液与姜黄素的乙醇溶液、50%乙醇溶液强光照射下的姜黄素降解情况,研究水对其光降解的影响;对不同pH下姜黄素立方液晶进行强光照射试验。结果以GMO/F127为处方制得的姜黄素立方液晶光稳定性较好;姜黄素在含水介质中,光降解速度加快;姜黄素立方液晶中的游离姜黄素在强光(4500Lx)照射下发生降解,而姜黄素立方液晶的光稳定性较好;酸对姜黄素立方液晶的光稳定性并无明显影响。结论结果表明姜黄素立方液晶对强光不稳定,光照环境下易发生降解,且水可加速姜黄素的光降解。该研究为姜黄素立方液晶的生产工艺及贮存条件选择提供可靠的实验依据。

Objective To investigate the photostability of curcumin and curcumin cubic liquid crystals by high performance liquid chromatography （HPLC） and the effect of water, ethanol and pH on the photostability of curcumin. Methods Curcumin cubic liquid crystals with different prescriptions were placed under different light conditions and the curcumin content was determined by HPLC-UV. By comparing the degradation of curcumin under strong light irradiation of curcumin cubic liquid crystals, curcumin ethanol solution, 50% ethanol solution, the influence of water on curcumin was studied. The curcumin cubic liquid crystals with different pH were selected for light irradiation tests. Results The curcumin cuboidal liquid crystals prepared by the method of GMO/F127 had a better photostability. The photodegradation of curcumin in water medium was accelerated. The free curcumin of curcumin cubic liquid crystals was degraded under the irradiation of strong light （4500Lx）, but the light stability of curcumin cubic liquid crystals was better than free curcumin. The photostability of curcumin cubic liquid crystals is not affected by acids easily. Conclusion The results showed that the curcumin cubic liquid crystals were unstable to light and degrade easily under light environment, and the water could accelerate the photodegradation of curcumin. The study provided a reliable experimental basis for the productive technology of curcumin cubic liquid crystals and the selection of storage conditions.