^(99m)Tc-Gd-DTPA-BMA的制备及其在荷瘤裸鼠体内的生物学分布

Preparation of ^(99m)Tc-Gd-DTPA-BMA and its bio-distribution in nude mice bearing tumor

目的探讨以99mTc标记Gd-DTPA-BMA的可行性及其在荷瘤裸鼠体内分布的特征。方法采用氯化亚锡还原法,用99mTc标记Gd-DTPA-BMA,TLC法测定99mTc-Gd-DTPA-BMA的放射化学纯度,将标记物注入荷A549肿瘤裸鼠体内,分别行SPECT显像及MRI增强成像,并测定其体内分布。结果 99mTc-Gd-DTPA-BMA放射化学纯度为99.2%,室温放置6 h后放射化学纯度大于95%。该标记物主要通过肾脏排泄,注射后肿瘤组织在SPECT及MRI下均能获得较好的显示或增强,且在肿瘤组织中具有较高的每克组织百分注射剂量率。结论作为一种潜在的双模式显像剂,99mTc-Gd-DTPA-BMA值得进一步研究。

Objective To explore the feasibility of using 99mTc labeled Gd-DTPA-BMA,and to observe its characteristics of distribution in nude mice bearing tumor.Methods The labeled compounds were prepared by reducing 99mTc in the presence of Gd-DTPA-BMA with stannous chloride（SnCl2）.The radiochemical purity was determined by TLC.99mTc-Gd-DTPA-BMA was injected into nude mice bearing A549 tumor.SPECT and MR imaging were performed,respectively.The in vivo bio-distribution in nude mice was observed.Results The radiochemical purity of 99mTc-Gd-DTPA-BMA was 99.2%,and remained more than 95% within 6 h at room temperature.99mTc-Gd-DTPA-BMA imaging and bio-distribution experiments showed that the marker was excreted by renal.After inject 99mTc-Gd-DTPA-BMA,SPECT and MRI showed the tumor tissue or enhancement clearly,and high percentage of the injected dose per gram of tissues mass was noticed.Conclusion As a potential dual-modal imaging agent,99mTc-Gd-DTPA-BMA is worthy of further research.