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

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１Ｈ ＮＭＲ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

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.