新型SPECT/MRI双模态显像剂SPION-DMSA-RGD-99 Tcm的合成与生物评价

摘要

为制备纳米材料 SPION-DMSA-RGD及其标记物 SPION-DMSA-RGD-99 Tcm ,探讨该标记物作为SPECT/MRI双模态显像剂的可能性,在水溶性纳米颗粒 SPION-DMSA 上连接 c(RGDfC),得到了SPION-DMSA-RGD,并进行了结构表征。用99 Tcm对 SPION-DMSA-RGD进行标记,并对该标记物进行了正常鼠和荷 U87MG人脑神经胶质瘤裸鼠的生物分布研究,及荷 U87MG 人脑神经胶质瘤裸鼠的MRI和 SPECT显像研究。研究结果表明,SPION-DMSA-RGD具有超顺磁性,99 Tcm标记率约为98%。正常鼠和荷 U87MG人脑神经胶质瘤裸鼠的生物分布结果表明,SPION-DMSA-RGD-99 Tcm在血液中清除较快,在肝脏中摄取较高,在肿瘤中有摄取。荷 U87MG人脑神经胶质瘤裸鼠的 MRI和 SPECT显像结果表明,SPION-DMSA-RGD 和 SPION-DMSA-RGD-99 Tcm的肿瘤主动靶向作用明显。以上结果提示,对于荷U87MG人脑神经胶质瘤裸鼠,SPION-DMSA-RGD-99 Tcm是一种SPECT/MRI双模态显像剂。%In order to investigate the possibility of SPION-DMSA-RGD-99 Tcm as a SPECT/MRI dual-modal imaging agent, SPION-DMSA-RGD and its radiolabeled SPION-DMSA-RGD-99 Tcm were prepared.SPION-DMSA-RGD was prepared based on SPION-DMSA and c(RGDfC).SPION-DMSA-RGD was characterized by means of vari-ous methods.SPION-DMSA-RGD-99 Tcm was given by labeling with 99 Tcm .The biodis-tribution studies of SPION-DMSA-RGD-99 Tcm in normal mice and the nude mice bearing U87MG human glioma were performed.The MRI and SPECT imaging of SPION-DMSA-RGD and SPION-DMSA-RGD-99 Tcm in the nude mice bearing U87MG human glioma were carried out,respectively.The results show that SPION-DMSA-RGD ex-hibits super-magnetic properties.The labeling yield of SPION-DMSA-RGD with 99 Tcm is about 98%.SPION-DMSA-RGD-99 Tcm displays fast clearance from the blood and high accumulation in the liver.The tumor uptake of SPION-DMSA-RGD-99 Tcm is higher than that of SPION-DMSA-99 Tcm .The MRI and SPECT images show that the tumor active targeting of SPION-DMSA-RGD and SPION-DMSA-RGD-99 Tcm are obvious. Therefore,SPION-DMSA-RGD-99 Tcm can be acting as a SPECT/MRI dual-modal ima-ging agent for nude mice bearing U87MG human glioma.