【摘要】 目的制备胶质瘤靶向诊疗一体化纳米粒,观察体外多模态显像及对U87细胞主动靶向能力和增效声动力治疗(SDT)效果。方法以双乳化法制备载IR780和全氟戊烷(PFP)纳米粒(IR780-PFP@PLGA),验证其体外光声(PA)/超声(US)/荧光(FL)多模态显像能力;以细胞计数试剂盒(CCK-8)检测细胞毒性,激光共聚焦显微镜观察其主动靶向能力,通过单线氧荧光探针(SOSG)检测法、JC-1染色法、2’,7’-二氯荧光黄双乙酸盐(DCFH-DA)染色法、钙黄绿素/碘化丙啶(Calcein-AM/PI)双染及CCK-8评价其增效SDT效果。结果所制备IR780-PFP@PLGA呈圆形,形态规则,粒径均匀,平均(240.67±1.30)nm,表面电位(-9.50±0.06)mV,IR780包封率(92.03±0.42)%;经激光辐照后其PA和FL信号强度呈浓度依赖性,经低强度聚焦超声(LIFU)辐照后表现出良好US对比度成像能力和较强U87细胞靶向能力,并呈活性氧(ROS)浓度依赖。于U87细胞中检出大量ROS,线粒体膜电位明显降低,细胞毒作用明显。结论成功构建的IR780-PFP@PLGA不仅可用于PA/US/FL多模态显像并具有良好体外寻靶能力,还可通过声致相变(ADV)增强SDT疗效,有望用于多模态成像指导下早期诊断和靶向精准治疗脑胶质瘤并评估疗效。更多还原

【Abstract】 Objective To prepare glioma-targeted theranostic nanoparticles(NP) and observe the ability of in vitro multimodal imaging, as well as to investigate the active-targeting ability and enhanced sonodynamic therapy(SDT) on U87 cells of glioma-targeted theranostic NP. Methods NP loaded with IR780, perfluoropentane(PFP) and IR780-PFP@PLGA were prepared using double emulsion method. The in vitro photoacoustic(PA)/ultrasound(US)/fluorescence(FL) multimodal imaging abilities of NP were verified. The cytotoxicity was tested with cell counting kit-8(CCK-8), the active-targeting ability was observed using confocal laser scanning microscope, while the enhanced SDT was evaluated with SOSG assay, JC-1 staining, DCFH-DA staining, Calcein-AM/PI double staining and CCK-8. Results IR780-PFP@PLGA presented symmetric size and regular spherical shape. The average size was(240.67±1.30) nm, and the zeta potential was(-9.50±0.06) mV. The encapsulation efficiency of IR780 in IR780-PFP@PLGA was(92.03±0.42)%. After laser irradiation, the signal intensities of PA and FL imaging were proved concentration-dependent. After low-intensity focused ultrasound(LIFU) radiation, IR780-PFP@PLGA exhibited good US contrast imaging ability and strong U87 cells-targeting ability, and the concentration of reactive oxygen species(ROS) was dependent. A large amount of ROS was detected in U87 cells, and the mitochondrial membrane potential decreased obviously, further led to obvious cytotoxic effects. Conclusion The successfully constructed IR780-PFP@PLGA could not only be used for PA/US/FL multimodal imaging because of excellent capability for in vitro targeting, but also enhance the efficacy of SDT through acoustic droplet vaporization(ADV) effect, which was expected to be used in early diagnosis, precision therapy and efficacy evaluation of glioma under the guidance of multimode imaging.更多还原