核壳结构表阿霉素靶向纳米粒及其体外光热化疗联合作用研究

Core-shell structured targeting nanoparticles loaded with epirubicin and its in vitro study of the combined effect of chemotherapy and photothermal therapy

目的制备具有高光热转换效率的核壳结构磷脂包覆装载表阿霉素的聚多巴胺杂合靶向纳米粒(lipid-coated hybrid polydopamine-cysteine cores for the delivery of epirubicin,E/PCF-NPs),并对其进行了表征和光热化疗体外联用作用研究。方法采用改进的氧化自聚合法制备聚多巴胺杂合内核(dopamine to form hybrid PDA-cysteine cores,PDAC cores),利用甲醇注入法制备得到E/PCF-NPs。绘制光照下温度时间变化曲线评价纳米粒光热转化性能;采用超滤法与高效液相色谱仪测定包封率及载药量;透射电镜(transmission electron microscopy,TEM)、原子力显微镜(atomic force microscopy,AFM)、扫描电镜(scanning electron microscopy,SEM)评价纳米粒结构;通过测定Zeta电位、粒径分布、贮存及血浆稳定性、体外释放考察纳米粒理化性质;采用噻唑蓝[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide),MTT]测定纳米粒的细胞毒性。结果PDA-NPs具有稳定光热转换性能及极低的衰减率。E/PCF-NPs的粒径为(106.7±2.4)nm,Zeta电位为(-46.7±5.28)mV,TEM、SEM、AFM显示纳米粒子呈球形或类球形,粒径分布均匀。表阿霉素包封率为(99.7±0.4)%,载药量为(10.26±0.04)%,且具有良好的贮存及血浆稳定性。体外释放表明E/PCF-NPs中表阿霉素的释放具有pH敏感性,且在近红外光照射下释放加快。细胞毒性证实在光照下可联合化疗药物实现更强细胞毒性。结论E/PCF-NPs光热转换性能良好,可实现表阿霉素的高效包封及缓释,在体外联合光热治疗后具有高抗肿瘤活性。

Objective To prepare the dual-targeted epirubicin-hybrid polydopamine nanoparticles(E/PCFNPs)with high photothermal conversion efficiency,and evaluate the combined effect of chemotherapy and photothermal therapy of E/PCF-NPs in vitro.Methods PDAC cores were prepared by improved oxidative self-polymerization method.E/PCF-NPs were prepared by methanol injection method.Photothermal conversion performance of nanoparticles was evaluated by the temperature-time curve under near infrared;ultrafiltration and high performance liquid chromatography were used to determine the entrapment efficiency and drug loading efficiency;transmission electron microscopy(TEM),atomic force microscopy(AFM)and scanning electron microscopy(SEM)were used to evaluate the structure of nanoparticles;Zeta potential,particle size distribution,stability,in vitro release were used to investigate the physical and chemical properties of nanoparticles.The cytotoxicity of nanoparticles was determined by MTT assay.Results PDANPs had stable photothermal conversion performance and very low attenuation rate.The particle size of E/PCF-NPs was(106.7±2.4)nm,and the Zeta potential was(-46.7±5.28)mV.TEM,SEM and AFM showed that the nanoparticles were spherical or quasi spherical with the uniform particle size distribution.The entrapment efficiency of epirubicin was(99.7±0.4)%,and the drug loading was(10.26±0.04)%with a good stability.The release of epirubicin from E/PCF-NPs was pH-sensitive and was accelerated under near-infrared light.It was confirmed that the combination of chemotherapy drugs and photothermal therapy can achieve stronger cytotoxicity.Conclusion E/PCF-NPs has good photothermal conversion performance,can achieve the high efficiency encapsulation and sustained release of epirubicin,and has high antitumor activity after combined photothermal therapy in vitro.