【摘要】 ^99mTc标记的外消旋六甲基丙二胺肟(^99mTc-d,1-HM-PAO)是一种理想的局部脑血流量灌注显像剂。由于改进了合成和分离同分异构体的方法,得到了纯度大于99％的外消旋六甲基丙二胺肟（d,1-HM-PAO）和纯的内消旋六甲基丙二胺肟（meso-HM-PAO）。简化分离步骤时,利用¹H NMR技术监测分离过程中两种异构体的相对含量,可保证d,1-HM-PAO配体的纯度。将新鲜^99mTc洗脱液加入无菌无热原冻干药盒试剂中,即形成^99mTc-d,1-HM-PAO静脉注射液,^99mTc-d,1-HM-PAO的放化纯度大于80％。小白鼠体内分布实验表明,^99mTc-d,1-HM-PAO在脑中的摄取量为2.24％I.D.,在脑内滞留时间达到24h时,仍有摄取量的72％的放射性保留在脑内。而^99mTc-meso-HM-PAO的脑摄取量为1.93％I.D.时,在脑内清除较快,至24h时,只有最初摄取量的25％残存在脑内。更多还原

【Abstract】 The 99mTc-d,l-HM-PAO is an ideal radiopharmaceutical for regional cerebral blood perfusion imaging. The improvement of synthesis and separation of diastereoiso-mers leads to obtain high purity (>99%)of d,1-HM-PAO and meso-HM-PAO. During separation H NMR spectroscopy was used to monitor the relative composition of these two diastereoisomers that can ensure the purity of pligand of d, 1-HM-PAO. The intravenous injection of 99m Tc-d. 1-HM-PAO was formed by adding fresh 99mTc washing liquor into a sterile, pyrogen-free and freeze-dried vial. The radiochemical purity (RCP)of 99mTc-d, 1-HM-PAO was greater than 80%. From the experiments of 99mTc-d, 1-HM-PAO in mice, after two minutes of intravenously (I. V. ) administration about 2. 24% of injected dose (I. D. ) appeared in the brain, and after 24 hours about 72% of radioactivity of injected dose still left in the brain. But for the 99m Tc-meso-HM-PAO. after two minutes of i. v. administration, about 1. 93% of I. D. appeared in the brain, and 24 hours later, 25% of radioactivity of I. D. was in the brain. This result shows that in the brain the radioactivity of 99m Tc-meso-HM-PAO declines faster than that of 99m Tc-d, 1-HM-PAO.更多还原