原子吸收光谱法间接研究组氨酸锌的配合反应

编程计算了不同pH条件下的组氨酸和锌离子的各种存在形式并分析了拟合分布图，研究了在硫化锌法原子吸收间接测定组氨酸时的pH值对原子吸收响应的影响及络合反应的机理。指出在pH 9.5左右最佳测定条件下，所形成的可溶性组氨酸锌配合物是由电中性的组氨酸基His+- 和带负一价电荷形态的组氨酸基His-与Zn(OH)₂共同形成的Zn(OH)₂·(C₆N₃O₂H₉)₂,Zn(OH)₂·[(C₆N₃O₂H₈)-]₂,Zn(OH)2·(C₆N₃O₂H₉)·[(C₆N₃O₂H₈)-]。结果表明，理论计算分析的结果与实验数据基本吻合，确定了硫化锌法原子吸收间接测定组氨酸时的配合物反应机理及配合物的组成结构。

Indirect Studies of Zinc-Histidine Complex Reaction by FAAS

Each state of histidine and zinc ion in aqueous solution with different pH was calculated by computer, producing the scatter diagram. Under the influence of solution pH, the mechanism of complex reaction in indirectly determining histidine by flame atomic absorption spectrometry with ZnS was studied. In different state of histidine and zinc ion in aqueous solution at differential pH, the response peak with pH in giving conditions was obtained. The soluble complex ion is composed of 0 valence histidine His+- and -1 valence histidine His+- and Zn(OH)2. The theoretical analysis from computing and scatter diagram agrees very well with the data determined from the experiments. The structures of complex ion are Zn(OH)2 x (C6N3O2H9)2, H8) Zn(OH)2 x [(C6N3O2H8)-]2 and Zn(OH)2 x (C6N3O2H9) x [(C6N3O2H8)-].