模拟分析体内外^(153)Sm-EDTMP热力学平衡组分  

Simulation Analysis of Sm-EDTMP in Vitro and in Blood Plasma

作　　者：蒋树斌[1] 罗顺忠[1] 

机构地区：[1]中国工程物理研究院核物理与化学研究所,四川绵阳621900

出　　处：《同位素》2003年第4期165-170,共6页Journal of Isotopes

基　　金：中国工程物理研究院科学基金资助项目(20020537)

摘　　要：引入Ca2+、Fe3+、Zn2+等金属离子和氨基酸、柠檬酸、乳酸等小分子配体建立了血液的金属离子-小分子配体热力学平衡模型,通过在该模型中添加Sm3+与小分子配体以及EDTMP与金属离子的热力学稳定常数,模拟分析了153Sm—EDFMP在血液中的平衡组分。结果表明,体外水溶液中,在pH7.4时,EDTMP主要以[EDTMPH2]-6和[EDTMPH2]-5形式存在,体系pH越低,配体平衡组分所含负电荷越少;相反,体系pH越高,配体含负电荷愈多,说明高pH有利于配合物的制备,同时也说明较高pH有利于配合物的稳定。体外研究还表明,Sm-EDTMP在体外主要以[Sm—EDTMP]-5、[Sm—EDTMPH-1]-6、[Sm—EDTMPH]-4等含高负电荷的配合物形式存在,说明如果配合物在体内不发生大的组分变化,则通过肾排泄,不会有高的肝摄取。体内组分分析显示,配合物在血液中主要以[Sm—EDTMPH]-4形式存在,说明即使在体内达到热力学平衡,配合物仍会经肾排泄;配合物的高负电荷说明配合物与HA的Ca2+有强静电吸附能力,提示配合物有较高的HA摄取。A thermodynamic equilibrium model, consisting of stability constants of major metal-ions and low molecular weight molecules ligands in human blood plasma, are made to analyze the constituent concentrations of Sm-EDTMP in vivo. The simulation analysis with computer program pack Hyperqud 2 000 indicats that the ligand EDTMP existes mainly in the forms of [EDTMPH2]-4 and [EDTMPH3]-5 in vitro at physiologic pH value and the net negative charge of ligand decreased with lowering pH. So, higher pH is favorable to form and stabilize Sm-EDTMP. The research results about Sm-EDTMP show that the complex existe mostly in the forms of [Sm-EDTMP]-5, [Sm-EDTMPH-1]-6 and [Sm-EDTMPH]-4 in vitro at pH 7. 4 which imply the complex will excrete mostly by kidney and be less harmful to liver. Sm-EDTMP study results with thermodynamic equilibrium model in blood plasma show that the complex is with -4 charge in the form of [Sm-EDTMPH]-4. The large negative charge of Sm-EDTMP provides, the power of chemisorption to HA.

关 键 词：153SM-EDTMP 热力学平衡模型 模拟分析 

分 类 号：O615.4[理学—无机化学] TQ463.7[理学—化学]