肝ASGP受体功能显像剂的制备及显像研究

Preparation and imaging study of a hepatic receptor imaging agent

采用ＦＰＬＣ快速纯化人血清白蛋白，利用双功能试剂２－亚胺基－２－甲氧基乙基－１－疏代－ 半乳糖甙与伯胺基的成脒反应，将硫代半乳糖残基引入人血清白蛋白分子，得到平均糖密度为 ３０的新半乳糖人血清白蛋白（ＮＧＡ）；用直接法制备９９ｍＴｃ－ＮＧＡ，其放化纯大于９０％，且室温下 可稳定６ｈ以上，符合显像要求。９９ｍＴｃ－ＮＧＡ小鼠体内分布实验及大鼠、兔和狗的显像研究均 表明９９ｍＴｃ－ＮＧＡ能够被肝脏特异摄取，且具有饱和性，主要通过胆道、肠道排泄，是一种较 好的肝ＡＳＧＰ受体功能显像剂。

Human serum albumin (HSA) was purified by FPLC with HiTrap Q column. Galactosyl neoglycoalbumin (NGA) was synthesized by the covalent coupling of a bifunctional reagent, 2-imino-2-ethyloxymethyl- 1-thiogalactose, to HSA. The average number of galactose groups was 30 in each NGA. NGA was labeled directly with Na99mTcO4. The radiochemical purity of 99mTc-NGA was over 90%. Biodistribution in mice, liver imaging in rat, rabbit and dog all show that 99mTc-NGA is a good hepatic receptor imaging agent.