4-羟基-3-对硝基苯偶氮基苯基荧光酮分光光度法测定植物中的微量钼

Determination of Trace Molybdenum in Plants by Spectrophotometry with 4-hydroxy-3-nitrophenyl Azo Phenylfluorone

设计并合成了未曾报道的4-羟基-3-对硝基苯偶氮基苯基荧光酮试剂;研究了荧光酮试剂与钼的显色反应最佳条件和金属络合物的特性。在pH为4.68的HAc-NH3缓冲溶液与表面活性剂TritonX-100的存在下,钼与荧光酮试剂形成了稳定的红色络合物。该络合物的最大吸收波长位于540 nm处,表观摩尔吸光系数为ε=7.3×104L/(mol.cm),钼含量在0～20μg/25 m范围内符合比耳定律。拟定方法应用于植物中微量钼的测定,方法简便灵敏且结果满意。

New reagent 4-hydroxy-3-nitrophenyl azo benzene fluorone was synthesize; In the presence of surfactant TritonX- 100 and HAc-NH3 buffer solution, reaction conditions and photometric properties of fluorone reagents with molybdenum were stud- ied. The results showed that the molar ratio of molybdenum and fluorone reagents formed the red complex, the maximum absorption wavelength of complex was 540 nm and the apparent molar absorptivity was 7.3x104 the buffer solution （pH= 4.68 of HAc-NH3） . Beer＇s law was obeyed when the content of molybdenum was in the range of 0-20μg/25ml. The developed method has been applied to the determination of trace molybdenum in plants with satisfactory results.