Zhao Guanghui, Wang Jianzhi, Peng Xiaomen, Li Yanfeng, Yuan Xuemei, Ma Yingxia
State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000 (P.R. China), Fax: (+86) 931-8912113.
Chem Asian J. 2014 Feb;9(2):546-53. doi: 10.1002/asia.201301072. Epub 2013 Nov 20.
We report a facile fabrication of a host-metal-guest coordination-bonding system in a mesostructured Fe3O4/chitosan nanoparticle that can act as a pH-responsive drug-delivery system. The mesostructured Fe3O4/chitosan was synthesized by a solvothermal approach with iron(III) chloride hexahydrate as a precursor, ethylene glycol as a reducing agent, ammonium acetate as a porogen, and chitosan as a surface-modification agent. Subsequently, doxorubicin (DOX), acting as a model drug (guest), was loaded onto the mesostructured Fe3O4/chitosan nanoparticles, with chitosan acting as a host molecule to form the NH2-Zn(II)-DOX coordination architecture. The release of DOX can be achieved through the cleavage of coordination bonds that are sensitive to variations in external pH under weakly acidic conditions. The pH-responsive nature of the nanoparticles was confirmed by in vitro releases and cell assay tests. Furthermore, the relaxation efficiency of the nanoparticles as high-performance magnetic resonance imaging contrast agents was also investigated. Experimental results confirm that the synthesized mesostructured Fe3O4/chitosan is a smart nanovehicle for drug delivery owing to both its pH-responsive nature and relaxation efficiency.
我们报道了一种在介孔结构的Fe3O4/壳聚糖纳米颗粒中简便构建主体-金属-客体配位键合体系的方法，该体系可作为一种pH响应型药物递送系统。介孔结构的Fe3O4/壳聚糖通过溶剂热法合成，以六水合氯化铁为前驱体，乙二醇为还原剂，醋酸铵为致孔剂，壳聚糖为表面改性剂。随后，作为模型药物（客体）的阿霉素（DOX）被负载到介孔结构的Fe3O4/壳聚糖纳米颗粒上，壳聚糖作为主体分子形成NH2-Zn(II)-DOX配位结构。在弱酸性条件下，DOX的释放可通过对外部pH变化敏感的配位键的断裂来实现。纳米颗粒的pH响应特性通过体外释放和细胞试验得到证实。此外，还研究了该纳米颗粒作为高性能磁共振成像造影剂的弛豫效率。实验结果证实，合成的介孔结构Fe3O4/壳聚糖由于其pH响应特性和弛豫效率，是一种用于药物递送的智能纳米载体。
