替加氟-层状双金属氢氧化物纳米杂化物的制备及缓释性能研究

Synthesis and characterization of tegafur-layered double hydroxides nanohybrids

采用共沉淀法制备了非离子型抗癌药物替加氟-LDHs纳米杂化物,依据替加氟分子大小和替加氟-LDHs的通道高度推测出替加氟分子是沿长轴方向垂直于层板以重叠双层方式排列于LDHs层间。药物释放研究表明,替加氟-LDHs纳米杂化物具有明显的缓释效果,表明是有发展潜力的新型药物控释体系。在pH=7.2的缓冲溶液中的释放速率明显低于pH=4.8的缓冲溶液,而在纯水(pH=5.65)中的释放速率明显低于缓冲溶液;释放动力学过程符合准二级动力学方程。

The intercalation of tegafur into Zn-Al layered double hydroxide （LDHs） with Zn/Al molar ratio of 2. 0 was carried out using the coprecipitation method to obtain tegafur-LDHs nanohybrids. According to the gallery heights of the tegafur-LDHs nanohybrids and sizes of tegafur molecule, a probable morphology of tegafur molecules in the gallery of tegafur-LDHs nanohybrids was suggested, of which the tegafur molecules were intercalated into the gallery of LDHs with an overlapped bilayer along the long axis vertically-arranged to the LDHs layers. The release kinetics of tegafur from the tegafur-LDHs nanohybrids was investigated in pH = 4. 8 and 7. 2 buffer solutions and pure water （ pH = 5.65 ）. It was found that the tegafur-LDHs nanohybrids could control the release of tegafur, and the in vitro drug release from the nanohybrids was remarkably lower than that from the corresponding physical mixture, which showed that the drug-nanohybrids could be considered as a potential drug delivery system. The release rate of tegafur from the tegafur-LDHs nanohybrids at pH = 7. 2 buffer solution was remarkably lower than that in pH 4. 8 buffer solution, and that at pure water （ pH = 5.65 ） was remarkably lower than that in buffer solutions. In addition, the release processes may fit pseudo-second-order release kinetics.