本研究中，首先合成kethoxal bis-N4-dimethyl-thiosemicarbazone ( KTSM2 )、3,3,9,9-tetramethyl-2-nitroimidazol-4,8-diazaundecane- 2,10-dione dioxime ( PnAO-2-nitroimidazole ) 及4,9-diaza-3,3,10,10- tetramethyldodecane-2,11-dione dioxime ( Bn(AO)2 )三種化合物，再從Mo-99發生器取出鎝99m標記，配製成為鎝99m金屬錯合物，然後進行放射化學純度分析，從氯仿/緩衝液分配係數測定、薄層層析、電泳分析及穩定性試驗，到最後缺氧及富氧環境的細胞攝入以及C3H/HeN小鼠活體器官組織分佈試驗，以評估其作為缺氧組織造影診斷劑之潛力。
研究結果顯示KTSM2在pH4與鎝99m錯合後，可得到高萃取率(88％)、電中性、高穩定度的錯合物，PnAO-2-nitroimidazole及Bn(AO)2在pH9與鎝99m錯合後，可得到高萃取率(分別為91%及65%)、電中性、高穩定度的錯合物，而且99mTc-KTSM2、99mTc-PnAO-2-nitroimidazole及 99mTc-Bn(AO)2錯合物的的標誌效率均大於90%。在缺氧及富氧環境的細胞攝入試驗中，發現99mTc-PnAO-2-nitroimidazole及 99mTc-Bn(AO)2在缺氧環境第4~6小時之吸收，均比富氧環境之吸收大於兩倍以上，而99mTc-KTSM2則無明顯差異。在C3H/HeN小鼠活體器官分佈試驗中，發現99mTc-KTSM2、99mTc-PnAO-2-nitroimidazole及 99mTc-Bn(AO)2在血液中的清除率相當快，在注射後10分鐘分別可高達77% 、58% 及54%以上 ，在注射後10分鐘~60分鐘，99mTc-KTSM2、99mTc-PnAO-2-nitroimidazole及 99mTc-Bn(AO)2在肝臟中的劑量，是體內各器官劑量最高者，且在小腸的劑量亦是逐漸增加，這顯示這三個錯合物具有高親脂性及在C3H/HeN體內多是由肝膽道代謝而往腸道排泄之生物特性。

由研究結果顯示，三種配位子所製成之鎝99m標誌錯合物中，99mTc-PnAO-2-nitroimidazole和99mTc-Bn(AO)2具有偵測缺氧組織細胞的潛力，於未來可以應用於臨床惡性腫瘤、心肌梗塞及中風等疾病，做非侵襲性缺氧組織細胞診斷的評估。

In this study, kethoxal bis-N4-dimethyl-thiosemicarbazone ( KTSM2 )、3,3,9,9-tetramethyl-2-nitroimidazol-4,8-diazaundecane- 2,10-dione dioxime ( PnAO-2-nitroimidazole ), and 4,9-diaza-3,3,10,10- tetramethyldodecan-2,11-dione dioxime ( Bn(AO)2 ) were synthesized and subsequently l led with 99mTc to get radioactive complexes. L ling efficiency, lipophilicity, and stability of the 99mTc l led complexes were examined by the analytical methods including solvent extraction, thin layer chromatography, and electrophoresis. Finally, the uptakes of the 99mTc l led complexes by Nfsa cells exposed under hypoxic and aerobic conditions and biological distribution in C3H/HeN mice were undertaken to assess the potential of the 99mTc complexes for hypoxia imaging.
The results show that the complexes of 99mTc with KTSM2 formed at pH 4、with PnAO-2-nitroimidazole at pH 9, and with Bn(AO)2 at pH 9 were lipophilic、neutral, and stable. In addition, labeling efficiencies of these 99mTc -complexes were more than 90%. In vitro experiment, the uptakes of 99mTc-PnAO-2-nitroimidazole and 99mTc-Bn(AO)2 in hypoxic environment after 4~6 hours were 2 times more than those in aerobic environment. However, the uptake of 99mTc-KTSM2 showed no significantly difference between hypoxic and aerobic conditions. In biological distribution, the blood clearances of 99mTc-KTSM2、99mTc-PnAO-2-nitroimidazole, and 99mTc-Bn(AO)2 were very fast and % ID/g blood remained ＜ 55% at 10 min postinjection. The uptakes in liver by these 99mTc-complexes were higher than other organs, and an increasingly accumulated doses in the small intestines were observed between 10~60 min postinjection.

These results indicate that these 99mTc-complexes, due to high lipophilicity, mainly excrete via hepatobiliary way. By this work, 99mTc-PnAO-2-nitroimidazole and 99mTc-Bn(AO)2 are evaluated to have potential as hypoxia imaging agents.

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