通过水热法和表面修饰法制备了以CoFe2O4为内核、TiO2为外壳、用透明质酸修饰的HA@CoFe2O4-TiO2。利用场发射扫描电子显微镜(SEM)成像、能谱分析(EDS)、X射线衍射(XRD)、X射线光电子谱(XPS)、紫外-可见吸收光谱(UV-Vis)以及傅里叶变换红外光谱(FTIR)对复合纳米颗粒的理化性质进行表征。用细胞计数试剂(CCK-8)法研究HA@CoFe2O4-TiO2复合纳米颗粒在暗室条件下对白血病HL60细胞的毒性, 以及在光照条件下的光动力疗法(PDT)灭活效果。结合复合纳米颗粒的荧光光谱(FS)、细胞内活性氧(ROS)产量和摄取纳米颗粒水平分析, 初步探究CoFe2O4和透明质酸与TiO2结合影响PDT灭活HL60细胞的作用机制。试验结果表明, HA@CoFe2O4-TiO2形貌规则呈球形, 尺寸符合细胞摄取要求。CoFe2O4拓宽了TiO2的可见光响应范围。暗毒性试验表明, HA@CoFe2O4-TiO2复合纳米颗粒对HL60细胞的毒性较小。同时, 与TiO2和CoFe2O4-TiO2纳米颗粒相比, HA@CoFe2O4-TiO2对HL60细胞的光动力灭活效率高达82.6%, 表明其有望成为应用于体外PDT治疗白血病的光敏剂, 提高光动力效率及靶向性。

In this study, CoFe2O4-TiO2 was prepared by hydrothermal method, in which CoFe2O4 was the core and TiO2 was the shell, and HA@CoFe2O4-TiO2 was obtained by hyaluronic acid modification. The physicochemical properties of the nanocomposites were characterized by scanning electron microscopy (SEM) imaging, energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible absorption spectroscopy (UV-Vis) and Fourier transform infrared spectroscopy (FTIR). CCK-8 method was used to investigate the toxicity of HA@CoFe2O4-TiO2 nanocomposites on HL60 cells in dark chamber, and the inactivation effect of photodymanic therapy (PDT). The mechanism of interaction between CoFe2O4, hyaluronic acid and TiO2 on PDT inactivation of HL60 cells was preliminarily investigated by fluorescence spectra (FS), intracellular ROS production and uptake level analysis of nanocomposites. The experimental results showed that the morphology of HA@CoFe2O4-TiO2 was regular and spherical, and the size met the requirements of cell uptake. The visible response range of TiO2 was broadened with CoFe2O4. Dark toxicity experiment proved that HA@CoFe2O4-TiO2 nanocomposites were less toxic to HL60 cells under darkroom conditions. Meanwhile, Compared with the groups treated with TiO2 and CoFe2O4-TiO2 nanoparticles, the photocatalytic inactivation efficiency of the group treated with HA@CoFe2O4-TiO2 was as high as 82.6%. Therefore, it has the potential to become a photosensitizer for the PDT treatment of leukemia in vitro, improving photodynamic efficiency and targeting.