生物靶向诊疗一体化探针多模态成像及增效高强度聚焦超声的实验研究

Multi-Modal Imaging and Synergistic High Intensity Focused Ultrasound with Bio-targeted Theranostic Probes:An Experimental Study

目的制备生物靶向诊疗一体化探针,观察其靶向肿瘤的能力,探讨其体外多模态成像的能力与对高强度聚焦超声(HIFU)的增效作用。材料与方法制备包裹吲哚菁绿(ICG)和全氟己烷(PFH)的阳离子纳米粒,将纳米粒与双歧杆菌通过静电吸附法相连,检测两者的连接率。组织切片验证生物靶向探针靶向肿瘤的能力。以阳离子纳米粒组为实验组,磷酸缓冲液(PBS)组为对照组,对比验证生物靶向探针多模态成像以及增效HIFU的能力。结果完成生物靶向诊疗一体化探针的制备,其中阳离子纳米粒径为(330.75±0.75)nm,双歧杆菌与阳离子纳米粒体外连接率高达(99.14±0.55)%。切片显示,该探针对肿瘤具有较好的靶向性,体外成像实验表明,纳米探针具有荧光,光声成像能力。激光辐照前后阳离子纳米粒组声强差值与PBS组比较,差异有统计学意义[(56.67±4.73)dB比(5.33±4.51)dB,t=13.612,P<0.001]。HIFU辐照后,PBS组与纳米粒组灰度变化(t=-18.272,P<0.001)、凝固性坏死体积(t=-7.301,P=0.002)、能效因子(t=5.451,P=0.006)差异均有统计学意义。结论制备的生物靶向诊疗一体化探针对肿瘤具有良好的靶向性,不仅可以运用于肿瘤诊断,还能协同HIFU增强对肿瘤的治疗效果,有望实现肿瘤的精准诊疗。

Purpose To develop an bio-targeted theranostic probe,observe its ability of precisely targeting tumors,and explore the imaging effect of multimodal imaging in vitro and the synergistic effect of high intensity focused ultrasound(HIFU).Materials and Methods Cationic lipid nanoparticle encapsulated with indocyanine green and perfluorohexane was prepared.Bifidobacterium and nanoparticles were connected by electrostatic adsorption method to detect their in vitro connectivity.Tissue sections were used to verify the tumor targeting ability of bio-targeted theranostic probe.The cationic nanoparticles group was used as the experimental group,and the PBS group was used as the control group to compare and verify the ability of bio-targeted theranostic probe multimodal imaging and synergistic HIFU.Results The integrated probe for biological targeted diagnosis and treatment was prepared,among which the average size of cationic lipid nanoparticles was(330.75±0.75)nm,and the in vitro connection rate between bifidobacterium and cationic lipid nanoparticles was as high as(99.14±0.55)%.Tissue sections showed that the probe had good targeting ability to tumor tissues.In vitro imaging experiments showed that the nanoprobe had fluorescence and photoacoustic imaging abilities.The difference of echo intensity between the cationic nanoparticles group before and after laser irradiation was(56.67±4.73)dB,which was statistically significant compared with the control group[(5.33±4.51)dB,t=13.612,P<0.001].After HIFU irradiation,there were statistically significant differences in gray level between PBS group and nanoparticle group(t=-18.272,P<0.001),volume of coagulation necrosis(t=-7.301,P=0.002)and emergency efficiency factor(t=5.451,P=0.006).Conclusion The bio-targeted theranostic probe has good targeting ability to tumors.It can not only be used as multi-modal imaging agents in the diagnosis of tumors,but also enhance the therapeutic effect of HIFU,which is expected to achieve accurate diagnosis and treatment of tumors.