聚乙二醇—硫酸铵—邻二氮菲体系萃取光度法测定铁的研究

建立了在聚乙二醇—硫酸铵—邻二氮菲体系中非有机溶剂萃取光度法测定铁的新方法 ,方法基于在 p H=5.8的缓冲溶液中 ,低价铁与邻二氮菲形成稳定的 1∶ 3的配合物 ,被萃取到高聚物相 ,其配合物的最大吸收波长位于 50 8nm、摩尔吸光系数ε=1 .1× 1 0 4 ( mol· cm) -1。在铁含量为 0～ 50μg范围内服从比尔定律 ,此法已用于生物样品中微量铁的测定 ,结果满意

Study on Spectrophotometric Determination of Iron Using Polyethylene Glycol-ammonium sulfate-1, 1O-phenanthroline as Extracting System

A new spectrophotometric method for the determination of iron by using polyethylene glycol ammonium sulfate 1,10 phenanthroline as extractant and color developing agent in inorganic solvents was estabtished. This complex was extracted by polyethylene glycol from water solution of pH 5.8. The maximum absorption of the complex is at 508 nm and the molar absorptivity is 1.1×10 4 L/(mol·cm). Beer's law was obeyed in the range of 0~50 μg. Fe(Ⅱ) and 1,10 phenanthroline formed a stable complex with molar ratio of 1∶3. The proposed method was applied to the determination of iron in bio sample with satisfactory results.