新型SPECT/MRI双模态显像剂SPION-DMSA-RGD-~(99)Tc~m的合成与生物评价

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 Tc m是一种SPECT/MRI双模态显像剂。

Synthesis and Biological Evaluation of SPECT/MRI Dual-modal Imaging Agent SPION-DMSA-RGD-99Tcm

In order to investigate the possibility of SPION-DMSA-RGD-⁹⁹Tc^m as a SPECT/MRI dual-modal imaging agent, SPION-DMSA-RGD and its radiolabeled SPION-DMSA-RGD-⁹⁹Tc^m were prepared. SPION-DMSA-RGD was prepared based on SPION-DMSA and c(RGDfC). SPION-DMSA-RGD was characterized by means of various methods. SPION-DMSA-RGD-⁹⁹Tc^m was given by labeling with ⁹⁹Tc^m. The biodistribution studies of SPION-DMSA-RGD-⁹⁹Tc^m 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-⁹⁹Tc^m in the nude mice bearing U87MG human glioma were carried out, respectively. The results show that SPION-DMSA-RGD exhibits super-magnetic properties. The labeling yield of SPION-DMSA-RGD with ⁹⁹Tc^m is about 98%. SPION-DMSA-RGD-⁹⁹Tc^m displays fast clearance from the blood and high accumulation in the liver. The tumor uptake of SPION-DMSA-RGD-⁹⁹Tc^m is higher than that of SPION-DMSA-⁹⁹Tc^m. The MRI and SPECT images show that the tumor active targeting of SPION-DMSA-RGD and SPION-DMSA-RGD-⁹⁹Tc^m are obvious. Therefore, SPION-DMSA-RGD-⁹⁹Tc^m can be acting as a SPECT/MRI dual-modal imaging agent for nude mice bearing U87MG human glioma.