School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798.
J Pharm Sci. 2011 Jun;100(6):2379-90. doi: 10.1002/jps.22446. Epub 2010 Dec 23.
This study is to enhance the dissolution rate of a poorly water-soluble drug, quercetin, by fabricating nanocrystals using high-pressure homogenization. The particle size, crystallinity, dissolution, and antioxidant effects of fabricated quercetin nanocrystals have been investigated. Characterization of the original quercetin powder and nanocrystals was carried out by photon correlation spectroscopy (PCS), laser diffraction, scanning electron microscopy, differential scanning calorimetry (DSC), X-ray diffraction, dissolution tester, and so on. A PCS size of about 483 nm was obtained for the nanocrystals after 20 cycles of homogenization at 1500 bar. X-ray diffraction and DSC studies revealed that the lyophilized quercetin nanoparticles were crystalline after high-pressure homogenization. The percent dissolution efficiency, relative dissolution, mean dissolution time, difference factor (f(1)), and similarity factor (f(2)) were calculated for the statistical analysis. It was found that the dissolution of the drug nanocrystals was much higher than that of the pure drug at pH 6.8 and 1.2. The antioxidant activity and reducing power of the quercetin nanocrystals were more effective than the original quercetin.
本研究旨在通过高压均质法制备纳米晶体来提高难溶性药物槲皮素的溶解速率。考察了所制备的槲皮素纳米晶体的粒径、结晶度、溶解度和抗氧化作用。采用光子相关光谱（PCS）、激光衍射、扫描电子显微镜、差示扫描量热法（DSC）、X 射线衍射、溶出度测试仪等对原槲皮素粉末和纳米晶体进行了表征。在 1500 巴下进行 20 次均质循环后，纳米晶体的 PCS 粒径约为 483nm。X 射线衍射和 DSC 研究表明，经高压均质处理后冻干的槲皮素纳米颗粒为结晶性。对统计分析进行了计算，包括百分溶解效率、相对溶解度、平均溶解时间、差异因子（f(1)）和相似因子（f(2)）。结果发现，在 pH 值为 6.8 和 1.2 时，药物纳米晶体的溶解度远高于纯药物。槲皮素纳米晶体的抗氧化活性和还原能力比原槲皮素更有效。
