CAJ | 학술논문

目的制备一种钆-纳米金复合物作为光和磁双模态分子成像探针,评估其分子影像学应用的可行性.方法在成功研制的钆-介孔硅磁共振对比剂的基础上,利用聚乙烯亚胺(PEI)进行表面改性,进而挂接带负电荷的30 nm的金颗粒,制备钆-纳米金复合物.透射电镜观察其物理表面特性,X射线能谱仪测量钆、金等各元素所占比例,紫外吸收光谱仪测定其吸收光谱,皮秒条纹相机测定其时间分辨荧光光谱,利用核磁弛豫分散技术分析其纵向弛豫率R1,MTT法测定其细胞毒性,共聚焦荧光显微镜分析其在骨髓间充质干细胞的光学成像效果,透射电镜分析其在组织内的亚细胞分布,3.0 T核磁共振扫描仪观察其在脾脏肝转移瘤小鼠中的成像效果.结果 30 nm的金颗粒成功挂接在PEI包裹的钆-介孔硅分子探针上.X射线能谱仪分析其Gd和Au元素所占比例为6.74％和0.52％.紫外吸收光谱分析其在525 nm处和近红外749 nm处均有吸收峰.时间分辨荧光光谱表明其发光有一个宽的发光带(525～560 nm),发光峰位于550 nm.其纵向弛豫率R1为3.171 nmol-1·L·s-1.MTT法显示其细胞毒性甚微.裸鼠尾静脉注射4h后,透射电镜显示其组织内的纳米金颗粒被降解分离.其具有很好的细胞共聚焦荧光成像效果.裸鼠尾静脉注射30 min,肿瘤的磁共振图像明显强化.结论成功制备了光和磁双模态分子成像探针,为肿瘤的早期诊断提供了依据.
목적 제비일충구-납미금복합물작위광화자쌍모태분자성상탐침,평고기분자영상학응용적가행성.방법 재성공연제적구-개공규자공진대비제적기출상,이용취을희아알(PEI)진행표면개성,진이괘접대부전하적30 nm적금과립,제비구-납미금복합물.투사전경관찰기물리표면특성,X사선능보의측량구、금등각원소소점비례,자외흡수광보의측정기흡수광보,피초조문상궤측정기시간분변형광광보,이용핵자이예분산기술분석기종향이예솔R1,MTT법측정기세포독성,공취초형광현미경분석기재골수간충질간세포적광학성상효과,투사전경분석기재조직내적아세포분포,3.0 T핵자공진소묘의관찰기재비장간전이류소서중적성상효과.결과 30 nm적금과립성공괘접재PEI포과적구-개공규분자탐침상.X사선능보의분석기Gd화Au원소소점비례위6.74％화0.52％.자외흡수광보분석기재525 nm처화근홍외749 nm처균유흡수봉.시간분변형광광보표명기발광유일개관적발광대(525～560 nm),발광봉위우550 nm.기종향이예솔R1위3.171 nmol-1·L·s-1.MTT법현시기세포독성심미.라서미정맥주사4h후,투사전경현시기조직내적납미금과립피강해분리.기구유흔호적세포공취초형광성상효과.라서미정맥주사30 min,종류적자공진도상명현강화.결론 성공제비료광화자쌍모태분자성상탐침,위종류적조기진단제공료의거.
Objective To prepare a dual-modal nanoprobes with gadolinium and gold nanoparticles for optical and magnetic resonance imaging,and validate its efficiency in molecular imaging.Methods The gadolinium-gold nanocomposite particles were prepared by immobilizing negatively-charged 30 nm gold nanoparticles on polyethyleneimine (PEI)-treated surface of the gadolinium-mesoporous silica.For the prepared nanoparticles,we used transmission electron microscopy (TEM) to determine the surface physical properties,energy dispersive X-ray spectroscopy to determine the constitution ratios of gadolinium and gold,ultraviolet spectrometry to determine the absorption spectra,picosecond streak camera to determine the timeresolved fluorescence spectra,and nuclear magnetic relaxation dispersion to determine the longitudinal relaxivity (R1).Cell toxicity was measured by MTT;Optical imaging in bone-marrow mesenchymal stem cells was evaluated by confocal fluorescence microscopy;Biodistribution was detected by TEM;Dynamic contrastenhanced T1-weighted magnetic resonance (MR) images of metastatic liver tumors in the spleen were analyzed using a 3.0 T MR scanner.Results Black gold particles (30 nm) were successfully immobilized on the surface of PEI-coated gadolinium-mesoporous silica spheres.The atomic percent of gadolinium and gold is 6.74％ and 0.52％,respectively,according to energy dispersive X-ray spectroscopy.The ultraviolet absorption spectra revealed the absorption peaks at 525 nm and 749 nm.Time-resolved fluorescence spectra revealed a wide luminescence band (525～560 nm),with a luminescence peak at 550 nm.The relaxivity R1 was 3.171 nmol-1· L · s-1.The cytotoxicity is negligible as measured by MTL TEM indicated that the gold nanoparticles were separated from nanocomposites in the tissues at 4 h after injected into nude mice via tail vein.Optical imaging in cells are satisfactory.The significant enhancement of tumor MRI was demonstrated at 30 min after intravenous administration.Conclusion The optic-magnetic dual-modal molecular imaging nanoprobes were successfully prepared,and could provide a potential platform for the early diagnosis of cancer.