【摘要】 研究了吲哚乙酸与磷钼杂多酸在浓度为 0 .0 3 mol/L的硫酸介质中发生氧化还原反应 ,形成的还原产物 (钼蓝 )在 NH3-NH4Cl缓冲溶液 (p H8.4)中最大吸收波长为 314 nm,表观摩尔吸光系数 ε值为 3.5 4× 10 4L· mol-1·cm-1 ,吲哚乙酸含量在 5 .0× 10 -7～ 5 .0× 10 -5 mol/L范围内符合比尔定律 ,检出限为 1.0× 10 -7mol/L,对 2 .0 0× 10 -5 mol/L吲哚乙酸测定 10次的相对标准偏差为 6 .42 % ,加标回收率为 94.2 %～ 10 0 .1%更多还原

【Abstract】 A new method for the spectrophotometric determination of indoleacetic acid was proposed.In 0.03 mol/L H 2SO 4 ,molybdophosphate heteropoly acid was reduced by indoleacetic acid.The maximum absorption of the reaction product,molybdophosphate heteropoly blue,is at 314 nm,the apparent molar absorptivity is 3.54×10 4 L·mol -1 ·cm -1 .Beer′s law is obeyed over the concentration range of 5.0×10 -7 ～5.0×10 -5 mol/L indoleactic acid. The limit of detection is 1.0×10 -7 mol/L.Recoveries of standard addition were 94.2%～100 1% with precision of 6.42% RSD.更多还原