Radiolabeled fatty acids are used as tracers for myocardial metabolic imaging and currently 123I-iodophenyl pentadecanoic acid (IPPA) or 123I-β-methyl-iodophenyl pentadecanoic acid (BMIPP) are the agents of choice. However, 123I being a cyclotron-produced isotope, 99mTc-labeled fatty acids are more desirable substitutes to 123I-labeled fatty acids. Toward this, two fatty acids, having 11 and 12 carbon atoms respectively, modified with cysteine were synthesized in a four-step procedure. These ligands were then radiolabeled with 99mTc using the [99mTcN(PNP6)]2+ core. Formation of the complexes and determination of radiochemical yields were ascertained by HPLC technique. In vivo distribution of the complexes was carried out in Swiss mice and the results are compared with 125I-IPPA. Both the complexes showed fast clearance from the myocardium till 10 min post injection (p.i.) followed by retention in the myocardium till 30 min p.i. However, compared with the result obtained with 125I-IPPA, the amount of activity retained in the myocardium by the present complexes were low. Both the complexes showed rapid clearance from liver, lungs, and blood unlike the case with 125I-IPPA. Copyright © 2010 John Wiley & Sons, Ltd.
放射性标记的
脂肪酸被用作心肌代谢成像的示踪剂,目前 123I-iodophenyl pentadecanoic acid (
IPPA) 或 123I-β-methyl-iodophenyl pentadecanoic acid (BM
IPP) 是首选制剂。然而,123I 是一种回旋加速器产生的同位素,因此 99mTc 标记的
脂肪酸比 123I 标记的
脂肪酸更为理想。为此,我们通过四步程序合成了两种分别具有 11 和 12 个碳原子的
脂肪酸,并用半胱
氨酸对其进行了修饰。然后使用[99mTcN(
PNP6)]2+ 核心对这些
配体进行 99mTc 放射性标记。复合物的形成和放射
化学收率的测定均通过 HPLC 技术进行。复合物在瑞士小鼠体内的分布情况与 125I-
IPPA 进行了比较。两种复合物都显示在注射后 10 分钟内迅速从心肌中清除,然后在心肌中保留到注射后 30 分钟。然而,与 125I-
IPPA 的结果相比,本复合物在心肌中保留的活性量较低。与 125I-
IPPA 不同的是,这两种复合物都能迅速从肝脏、肺部和血液中清除。Copyright © 2010 John Wiley & Sons, Ltd. All Rights Reserved.