Sm-NTMP水溶液热力学平衡模拟

Aqueous thermodynamic equilibrium speciation simulation of Sm-NTMP

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 + 和NTMP ,模拟分析了153 Sm NTMP在血液中的平衡组分。结果表明 ,在总Sm浓度为 4× 10 6mol/L ,NTMP浓度为 4× 10 5mol/L条件下 ,体外生理pH水游离Sm3 + 浓度很低 ,Sm NTMP展现出高的体外稳定性 ;血浆模型中 ,生理pH水溶液中Sm NTMP主要以SmL2 形式存在 ,但存在一定量的Sm柠檬酸配合物 ,说明153 Sm NTMP虽然会有强的骨摄取 ,但也会有总NTMP浓度 ,Sm NTMP含量迅速提高 ,Sm

A thermodynamic equilibrium model, consisting of stability constants of major metal-ions and low molecular weight molecule ligands in human blood plasma,was proposed to analyze the constiuent concentrations of Sm-NTMP in vivo. With total Sm concentration of 4×10^(-6)mol/L, total NTMP concentration of 4×10^(-5)mol/L, computer simulation studies of Sm-NTMP with program pack Hyperqud 2000 indicate that the Sm-complexes existed mainly in the forms of [SmL_2]^(9-) and [SmHL]^(2-) and little free Sm^(3+) in vitro at physiologic pH value, which imply strong affinity of Sm-NTMP to HA and high stability of Sm-NTMP in vitro. Equilibrium studies of Sm-NTMP in blood plasma model show the complex existed mostly in the forms of [SmL_2]^(9-) but with 24.61% of Sm-Citrate which explain the high bone uptake, relatively high blood retention and liver uptake of 153Sm-NTMP. Research results also show that the blood retention and liver uptake of Sm-NTMP maybe reduce, the stability of Sm-NTMP may be promoted to a satisfied level in vivo by increase the total concentration of NTMP to 9.6×10^(-4)mol/L.