5′-硝基水杨基荧光酮分光光度法测定食品中铝

Spectrophotometric Determination of Aluminium in Food with 5'-Nitro-Salicylfluorone

研究铝与5′-硝基水杨基荧光酮在Tween-20增敏作用下的显色反应。在pH5.0的酸性介质中,铝与5′-硝基水杨基荧光酮(5′-NSF)和Tween-20形成紫红色的三元络合物,其最大吸收峰位于562nm处,摩尔吸光系数为1.17×105L(/mol·cm)。铝的质量浓度在0.02mg/L～0.20mg/L内符合比耳定律。方法的回收率为97.6%～101.4%。

The color reaction of aluminium（III）with 5＇-nitro-salicylfluorone in the presence of Tween-20 was studied.Aluminium reacts with 5-nitro-salicylfluorone to form a stable violet red complex in a buffer solution （pH 5.0）.The complex has a maximum absorption wavelength at 562 nm.The apparent molar absorptivity is 1.17×10^5 L（/mol·cm）.Beer＇s law is obeyed in the range of 0.02 mg/L-0.20 mg/L for aluminium.The recovery of the method was 97.6 %-101.4 %.