Azo功能化Fe_3O_4磁性纳米载体的载药条件优化及其表征

Optimization of delivery conditions and characterization of azo-functionalized Fe_3O_4 magnetic nanocarrier

目的:对所制备的Azo功能化Fe_3O_4磁性纳米载体的载药条件进行优化,以得到最佳载药方案。方法:对溶剂热法合成的亲水性磁性纳米Fe_3O_4进行表面修饰,在其表面连接乙二胺和4,4'-偶氮(4-氰基戊酸,Azo)得到表面具有羧基的Azo功能化Fe_3O_4磁性纳米载体。阿霉素(Dox)以酰胺键与纳米粒子相连接,从药物浓度、投料比、载药时间三个方面对载药条件进行优化。结果:通过对载药条件进行优化,确定最佳载药条件为:阿霉素浓度1 500μg/ml、投料比150μg/mg、载药时间20 min,最佳载药条件下的载药量为2.73%,包封率为18.2%。通过紫外吸收光谱对载阿霉素载体进行表征,验证了载体成功负载阿霉素,其在PBS缓冲液中稳定。结论:本试验通过对载药条件的优化,确定了最佳载药条件。

Objective : Delivery conditions of azo-functional Fe_3O_4 magnetic nanocarriers prepared were optimized to get the best drug-loading scheme. Methods: The hydrophilic Fe_3O_4 magnetic nanoparticles prepared by hydrothermal synthesis were modified using ethylenediamine and 4,4'-azobis(4-cyano-acid)(Azo) to attach to its surface successively to obtain azo-functional Fe_3O_4 magnetic nanocarriers with carboxyl groups. Doxorubicin(Dox) was linked to nanoparticles by amide bond. We optimized the delivery conditions from drug concentration, feed ratio and drug-loading time. Results: Optimal loading conditions consisted of drug concentration of 1 500μg/ml, feed ratio of 150 μg/mg and drug-loading time for twenty minutes. Under the optimal loading conditions, the drug loading capacity was 2. 73% and the encapsulation efficiency was 18. 2%. It was verified by UV absorption method that doxorubicin had been loaded by the carriers successfully. Conclusion : The stability of the carriers in PBS buffer was investigated.