中文摘要：

为发展锝-99 m标记的阿尔茨海默病（Alzhei mer’s disease,AD）早期诊断显像药物,在荧光测定法基础上,建立了体外荧光法测定羰基铼配合物与Aβ（1~40）淀粉样纤维结合的解离常数Kd的方法。同时,合成了配体2-（1-乙基苯并咪唑）吡啶（EPBI）及其铼的配合物Re（CO）3Cl（EPBI）,测定后者与体外缠结Aβ（1~40）结合的解离常数Kd;采用直接标记法制备EPBI的[^99Tc^m（CO）3]＋配合物,并研究配合物[^99Tc^m（CO）3]＋-EPBI的理化性质及生物分布。结果表明,Re（CO）3Cl（EPBI）与Aβ（1~40）结合的解离常数Kd=13.3μmol/L;正常小鼠体内生物分布研究表明,化合物[^99Tc^m（CO）3]＋-EPBI的脑初始（2 min内）摄取值为（0.63±0.17）%ID/g（n=3）,在脑内清除较快,120 min时,摄取值为（0.27±0.03）%ID/g（n=3）。

英文摘要：

The aim of this paper was to develop potential technetium 99m-labeled diagnostic imaging agents specific for the detection of Aβ plaques. Based on previously obtained All plaque-specific biphenyls containing a benzimidazol group, ^99Tc^m and Re-benzimidazol derivatives, [^99Tc^m（CO）3]^＋-EPBI and Re（CO）3Cl（EPBI）, were prepared. The latter showed binding affinities towards Aβ（1-40） aggregates in vitro （Kd = 13.3 μmol/L） by fluorophotometry. 2- （1-Ethylbenzimidazol-2-yl） pyridine （EPBI） and Re （CO） 3 Cl （EPBI） were synthesized. Binding affinity of Re（CO）3CI（EPBI） for Aβ（1-40） aggregates was determined. [^99Tc^m（CO）3]^＋-EPBI was prepared and analyzed by HPLC and paper eletrophoresis. Its biodistribution in mice was obtained. The Kd value of Re （CO）3Cl （EPBI） is 13. 3 μmol/L. Biodistribution of [^99Tc^m（CO）3]^＋ -EPBI in mice shows brain penetration （0. 63±0. 17）%ID/g （n=3） at 2 rain after iv injection in mice and rapid washout from normal brains （0. 27±0.03） %ID/g （n=3） at 120 min. It may provide a new strategy to design the early diagnosis radiopharmaceuticals of AD labeled by [^99Tc^m（CO）3]^＋ core according to the result.