中文摘要：

采用共沉淀法,以替加氟（Tegafur,TF）插层层状双金属氢氧化物（LDHs）纳米杂化物（TF-LDHs）包覆磁性基质Fe3O4,得到了具有核/壳结构的纳米复合体[Fe3O4@（TF-LDHs）],采用XRD,FTIR,TEM,VSM和元素分析等技术对样品的化学组成、晶体结构、形貌及磁性等进行了表征,探讨了药物分子在LDHs层间的存在状态,考察了其药物释放行为.结果表明,Fe3O4@（TF-LDHs）纳米复合体具有顺磁性,其比饱和磁化强度随磁性基质含量的增大而增强;TF分子在LDHs层间以长轴略倾斜于LDHs层板的方式呈双层排布;Fe3O4@（TF-LDHs）纳米复合体具有明显的药物缓释性能,其释放动力学过程符合准二级动力学方程,颗粒内部扩散为释放过程的速率控制步骤.

英文摘要：

A series of nonocomposite Fe3O4@（TF-LDHs） possessing a core/shell structure with a tegafur（TF） intercalated Zn-Al layered double hydroxides（LDHs） shell coated onto the surface of magnetic Fe3O4 core was assembled via one step coprecipitation method.The chemical composition,crystal structure,magnetic property,arrangements of TF within interlayer and drug release behavior of the magnetic nanocomposite were investigated systematically by XRD,FTIR,TEM,VSM,ICP and UV-Vis techniques.The results show that Fe3O4@（TF-LDHs） have a paramagnetism and the saturation magnetization were enhanced with increasing the magnetic substrates content.Tegafur molecules were arranged as a bilayer with the long axis slightly tilted to the LDHs layers.The release kinetics of TF from Fe3O4@（TF-LDHs） nonocomposite was investigated in pH=7.2 and pH=4.8 buffer solutions,and it was found that the release process might fit the pseudo-second-order release kinetics and the diffusion of tegafur through the LDHs particle played an important role in controlling the drug release rate.The in vitro drug release rate from the nanocomposite was remarkably lower than that from the corresponding physical mixture,which showed that the Fe3O4@（drug-LDHs） nanocomposites could be considered as a potential magnetic targeting drug delivery-controlled-release system.