^(117)Sn^m(Ⅳ)-EDTMP在体外骨模型上的吸附——Ⅰ.在羟基磷灰石上的吸附

Adsorption of ^(117)Sn^m(Ⅳ)-EDTMP on Hydroxyapatite

研究了^(117)Sn^m(Ⅳ)及^(117)Sn^m(Ⅳ)-EDTMP在体外骨模型羟基磷灰石(HA)上的吸附及解吸特性,探讨了其骨吸附机理。吸附研究表明:^(117)Sn^m(Ⅳ)及^(117)Sn(Ⅳ)-EDTMP在HA上都有明显的吸附,其对^(117)Sn^m(Ⅳ)的吸附量大于对^(117)Sn^m(Ⅳ)-EDTMP的吸附量;pH对吸附有明显影响,酸性条件最有利于吸附,弱碱性条件最不利于吸附;温度对吸附几乎没有影响。解吸研究表明:生理盐水和EDTMP对^(117)Sn^m(Ⅳ)-EDTMP的解吸量大于对^(117)Sn^m(Ⅳ)的解吸量。^(117)Sn^m(Ⅳ)-EDTMP的吸附机理研究初步表明:当吸附量小于60μmol/g时,络合物以整个配位络合物吸附为主;当吸附量大于60μmol/g时,配位络合物整体吸附与^(117)Sn^m(Ⅳ)从配体到HA的转移络合同时存在。

The adsorption characteristics of 117Snm(Ⅳ) and 117Snm( Ⅳ )-EDTMP on hydroxyapatite (HA) are studied. The adsorption mechanics of 117Snm(Ⅳ )-EDTMP is also investigated. The adsorption experiments on HA show that 117Snm( Ⅳ ) and 117Snm(Ⅳ )-EDTMP adsorb very rapidly. pH has great effect on the absorption of 117Snm( Ⅳ )-EDTMP on HA, and the acid environment is most favorable, however, the temperature has very slight effect on the absorption. The adsorption model of 117Snm( Ⅳ )-EDTMP is complicated: the quantitative adsorption takes place when the concentration is lower than 60 μmol/g; when the concentration is above this, the adsorption deviates from quantitative one, but still increases remarkably. Then the adsorption mechanics could be understand as the followings : in quantitative adsorption stage, what's adsorbed is the whole-labeled compound; in the deviation stage, what's adsorbed include both the labeled compound and the free 117Snm(Ⅳ) dissociated from it. The desorption experiments from HA show that EDTMP desorbs more 117Snm( Ⅳ )-EDTMP than 117Snm(Ⅳ ).