论文部分内容阅读
将具有邻苯二酚结构的多巴胺用于超小Gd2O3纳米粒子的表面修饰,通过控制反应时间,制得适用于磁共振成像(MRI)增强对比度的造影剂.通过透射电镜(TEM),红外光谱(FTIR),紫外-可见吸收光谱(UV-vis)及热重分析(TGA)测试表征了多巴胺修饰Gd2O3纳米粒子的形貌、结构及组成.结果表明:平均粒径为3.7nm的Gd2O3纳米粒子经多巴胺修饰后,由于多巴胺分子中苯环的疏水性导致了一定程度的聚集;反应12h和24h对应的多巴胺修饰的超小Gd2O3纳米粒子中有机物的组成分别为34.7%和42.6%.MRI造影结果显示,多巴胺表面修饰的超小Gd2O3纳米粒子有效地增强了对比亮度,且弛豫效率和信号强度在一定浓度范围内与造影剂浓度呈正相关;反应较长时间(24h)对应的多巴胺修饰的超小Gd2O3纳米粒子的弛豫效率较高,对应的造影增强效果更好.
The dopamine with catechol structure was used to modify the surface of ultra-small Gd2O3 nanoparticles, and the contrast agent was prepared to enhance the contrast by controlling the reaction time.Through transmission electron microscopy (TEM), infrared spectroscopy The morphology, structure and composition of dopamine-modified Gd2O3 nanoparticles were characterized by Fourier transform infrared spectroscopy (FTIR), UV-vis and TGA.The results showed that the average particle size of Gd2O3 nanoparticles After dopamine modification, the hydrophobicity of the benzene ring in the dopamine molecule resulted in a certain degree of aggregation. The composition of organic compounds in dopamine-modified ultra-small Gd2O3 nanoparticles at 12h and 24h after the reaction were 34.7% and 42.6%, respectively Showed that dopamine surface-modified ultra-small Gd2O3 nanoparticles effectively enhance the contrast brightness, and the relaxation efficiency and signal intensity in a certain concentration range was positively correlated with the concentration of contrast medium; reaction for a long time (24h) corresponding dopamine modified super The small Gd2O3 nanoparticles have higher relaxation efficiency and the corresponding contrast enhancement effect is better.