Marzilli L G, Worley P, Burns H D
J Nucl Med. 1979 Aug;20(8):871-6.
An electrophoretic procedure is outlined for the determination of the number of ligands bound to technetium-99m radiopharmaceuticals. The approach involves use of ligands that will complex technetium in a similar fashion but that differ in charge. This approach was applied experimentally to dimercapto ligands in which the ligating sulfur atoms are separated by a flexible three-carbon chain (1,3-dimercapto compounds). Two such ligands studied are 1,3-dimercaptopropane (DMP) and dihydrothioctic acid (DHTA). The Tc compound of DHTA migrates much farther on electrophoresis than the Tc complex of DMP. However, when TcO4- is reduced by SnCl2 or NaBH4 in the presence of equimolar quantities of DHTA and DMP, a new compound is formed being twice as abundant as either the TcDMP or the TcDHTA compound and migrating an intermediate distance. The formation of this new complex and the 1:2:1 distribution indicates that two 1,3-dimercapto compounds are attached to the Tc-center in all three compounds.
概述了一种用于测定与锝-99m放射性药物结合的配体数量的电泳方法。该方法涉及使用以类似方式与锝络合但电荷不同的配体。该方法通过实验应用于二巯基配体，其中连接硫原子由柔性三碳链（1,3-二巯基化合物）隔开。研究的两种此类配体是1,3-二巯基丙烷（DMP）和二氢硫辛酸（DHTA）。DHTA的锝化合物在电泳中迁移的距离比DMP的锝络合物远得多。然而，当在等摩尔量的DHTA和DMP存在下用SnCl2或NaBH4还原TcO4-时，会形成一种新化合物，其丰度是TcDMP或TcDHTA化合物的两倍，并迁移到中间距离。这种新络合物的形成和1:2:1的分布表明，在所有三种化合物中，两个1,3-二巯基化合物都附着在锝中心上。
