硫氰酸钾-邻菲啰啉-吐温-20分光光度法测定植物中的铁

SPECTROPHOTOMETRIC DETERMINATION OF IRON IN PLANT WITH POTASSIUM THIOCYANATE AND 1,10-PHENANTHROLINE IN THE PRESENCE OF TWEEN-20

本文研究了在吐温-20存在下，于硝酸介质中，铁（Ⅲ）与硫氰酸钾和邻菲啉的显色反应房件。结果表明，所形成的红色配合物的最大吸收波长为518nm，表观摩尔吸光系数为2.06×10～4L·mol-1·cm-1，铁（Ⅲ）含量在0～50μg范围内服从比耳定律。本法具有操作简便，选择性高，重复性好等优点，可不经分离和掩蔽，直接用于植物中铁的测定，结果满意。

It is reported that iron(Ⅲ) forms a red complex with potassium thiocyanate and 1,10-phenanthroilne in the presence of Tween-20 and in nitric acid solution. The absorption maximum wavelength of the complex is 518nm. and it's apparent mole absorptivity is 2. 06× 10~4 L· mol-1· cm^(-1). Beer's law is obeyed for iron in the range of 0-50μ g/25mL,correlation coefficient is 0. 9999. The advantages of this method are simple operation. less time-consuming. high selectivity and repeatability. It has been applied to determine iron in plant with satisfactory results, without the need for preliminary separation and masking steps.