^99Tc^m标记硫酸软骨素及其在小鼠体内的生物分布

采用亚锡还原法对硫酸软骨素（CS）进行了^99Tc^m标记，优化了标记条件，并观察标记物在小鼠体内的生物分布，为骨关节软骨显像提供依据。采用薄层层析分析标记产物的标记率为81．6％±1．7％；用直径为0．2p．m的无菌滤膜对标记液纯化，纯化后放化纯度为90．1％±1．2％^99Tc^m—CS在小鼠体内的生物分布结果显示，其在血液中清除较快，肾脏是主要排泄器官；有较高的亲软骨组织特性，4h时软骨与血液的放射性摄取比（T／NT）为8．31，软骨与骨的T／NT为2．03。以上结果提示，^99Tc^m-CS的标记方法简便，有一定的亲软骨组织性，有待进一步研究。

Labeling of Chondroitin Sulfate With 99Tcm and Its Biodistribution in Mice

The feasibility of direct labeling of chondroitin sulfate (CS) with 99Tcm was studied, and the effects of different conditions on labeling yield was observed，and the biodistribution of 99Tcm-CS in normal mice was investigated, chondroitin sulfate was labeled directly with 99Tcm reduction of 99TcmO4 with SnCl2 solution. The labeling yield and radiochemical purity were determined with thin layer chromatography （TLC）using Xinhua filter paper. The biodistribution of 99Tcm-CS in normal mice was studied at 30 min, 1 , 2, 4 and 8 h respectively after caudal vein injection in normal mice. The labeling yield was 81.6％±1.7％ and radiochemical purity was 90.1％±1.2％ after filtering by micropore membrane .The biodistribution in mice showed that 99Tcm-CS was cleaned out from blood quickly, and it was mainly excreted through kidney, but 99Tcm-CShad high specificity to cartilage go blood was 8.31（4 h）, the ratio of cartilage to bone was 2.03(4 h). 99Tcm-CS is an easily prepared and labeled compound with high philo-cartilage and stability.