BPHA二价金属离子配合物的结构与~(99)Tc~m-BPHA生物分布的关系

STRUCTURES OF M 2+ BPHA COMPLEXES AND THEIR RELATIONSHIP TO THE BIODISTRIBUTION OF ~(99) Tc m BPHA

摘要: 测定了Ｎ，Ｎ′－二胺乙基丙二胺六乙酸（ＢＰＨＡ）的加质子常数和它的二价金属离子配合物的加质子常数，不同ｐＤ值下ＢＰＨＡ和Ｚｎ２＋－ＢＰＨＡ的１ＨＮＭＲ谱。ｐＨ≈６时，ＢＰＨＡ二价金属离子配合物有一质子离去，并伴有重大的结构变化。ｐＨ＝７时，９９Ｔｃｍ－ＢＰＨＡ标记物的生物分布与ｐＨ＝４时９９Ｔｃｍ－ＢＰＨＡ标记物的生物分布不同。ｐＨ＝７时，９９Ｔｃｍ－ＢＰＨＡ具有优良的肾排泄性质

Abstract: The protonation constants of BPHA and its complexes of divalent metal ions Co 2+, Ni 2+, Cu 2+, and Zn 2+ are determined by potentiometric titration and non linear regression. The 1H NMR spectra of Zn 2+ BPHA at pD=2～12 is obtained on Varian 200. It proves that at pH≈6 the complex Zn(Ⅱ) H 2BPHA 2- loses a proton and a formerly free iminodiacetic acid moiety becomes coordinated; at pH≈9 the last proton is dissociated and an iminodiacetic acid moiety is released again. The 99 Tc m labelled product obtained at pH=7 is completely excreted through kidneys, different from the product forming at pH=4, which is taken up by liver considerably.