温度和pH敏感高分子含钆核磁共振成像造影剂的合成及性能

Synthesis and Proporties of Temperature and p H-sensitive and Gadolinium Contained Polymeric Magnetic Resonance Imaging Contrast Agent

以N-异丙基丙烯酰胺为温度敏感单体,以甲基丙烯酸为p H敏感单体,与三丙烯酸菲洛啉钆进行无皂乳液聚合,一步合成了具有温度和pH敏感的高分子含钆核磁共振成像（MRI）造影剂（TPRPP）.动态光散射测试结果表明,TPRPP的粒径随温度或p H值的变化而发生较大的改变.体外MRI测试结果表明,TPRPP的横向弛豫时间（T_1）的加权弛豫率约为11.3 L/（mmol·s）,为临床造影剂Magnevist~的2.6倍.体内MRI结果表明,TPRPP在肝和脾中具有明显的正增强效果.研究结果表明,TPRPP是一种优异的多功能MRI造影剂,具有极大的临床研究价值.

Paramagnetic,temperature and p H-sensitive polymeric particles were prepared with N-isopropylacrylamide,methacrylic acid,styrene,and polymerizable Gd（AA）_3phen·H_2O using emulsifier-free emulsion polymerization technique. Dynamic light scattering result shows that the diameter of the polymeric particles changes by about 60 nm as a result of variations in either the temperature or p H,indicating that the particles are p H and temperature-sensitive. The T1-weighted relaxivity values at 3 T are about 11. 3 L /（ mmol · s）which is 2. 6 times higher than clinical Magnevist~. In vivo MR imaging reveals that the TPRPPs can be effectively imaged in the liver and spleen,suggesting that they are excellent magnetic resonance imaging agents.