包裹放射性核素131I的高分子纳米药物的制备及其放射自显影实验

目的制备一种包裹放射性核素的纳米药物,并对其理化性质及放射性特征进行研究。方法采用高分子纳米材料聚乳酸/羟基乙酸(PLGA)作为载体,用放射线核素131I作为包裹药物,通过双乳化法和冷冻干燥技术制备包裹131I的PLGA纳米药物。并对其外观、形态及放射性特征进行观察分析,采用光镜、电镜及放射自显影术,检测其粒径、电位及其包裹放射性核素的能力。结果通过本方法成功制备了包裹放射性核素131I的高分子纳米药物;光镜下观察其形态规则、呈球形,大小均匀,平均粒径为(1.55±0.25)μm,电位为(-30.1±5.3)mv;包封率为(1.0±0.5)%;单个PLGA纳米药物的放射性活度约为1.1×10-2 Bq,单个纳米药物的比活度为5.2×10-3 Bq/nm3。体外放射自显影图像显影清晰,与空白对照组对比差异有统计学意义。结论包裹放射性核素131I的纳米放射性微球理化性质稳定,具有较高的包封率,放射性自显影效果好,为对放射性核素抵抗或不敏感的肿瘤核素诊断与治疗提供重要方法和思路,为进一步包裹放射性核素的靶向性纳米药物的研究奠定了基础。

Fabrication and characterization of radionuclide 131I-loaded poly (lactic acid-co-glycolic acid) nanoparticles

Objective To prepare 131I-loaded nanoparticles,and to study physicochemical and radioactive properties.Methods Biodegradable poly(DL-lactic acid-co-glycolic acid)(PLGA) nanoparticles loaded with radionuclide 131I were prepared by double emulsion solvent-evaporation technique.The appearance,mean diameter,and surface charge were detected.The 131I loading payload and radioactivity were measured.Results Uniform 131I-PLGA with narrow size distribution and smooth surface were produced.Autoradiography showed radioactivity associated with the PLGA nanoparticles.The encapsulation efficiency was(1.0±0.5)%.The radioactivity of each PLGA nanoparticle was about 1.1×10-2Bq,and the specific activity of single nanoparticle was about 5.2×10-3Bq/nm3.Conclusion 131I-PLGA nanoparticles have stable physical and chemical properties and reasonable encapsulation efficiency.It may provide an alternative for treatment of cancer resistant to conventional radiotherapy.