荧光法测定食盐中碘酸根的研究

在0.05 mol/L的H2SO4介质中,过量I-存在时,IO3-会使罗丹明B发生荧光猝灭,建立了测定IO3-的方法.该体系的荧光发射波长λ=580 nm,激发波长λ=557 nm,体系的荧光强度降低值与IO3-含量在0.6～1.6 μg/mL之间呈良好的线性关系.回归方程为△F=18.30 C＋119.5（C的单位μg/mL）,相关系数r=0.9810,检出限为0.0052 μg/mL.该法灵敏度较高,选择性好,操作简单,用于含碘食盐中碘酸根含量的测定,结果满意.

Study on Fluorescencent method for Determination of Iodate Ion in Table Salt

A highly sensitive and simple fluorescence quenching method is developed to determine iodate ion（IO3-）. The mothod is based on the 103- reacts with excess of potassium iodide in sulfuric acid solution （0.05 mol/L） which reacts with rhodamine B to produce a non fluorescent compound, thus quenching the fluorescence intensity of the system. The linear calibration range is 0.6-1.6 pg/mL with the fluorescence emission wavelength k = 580 nm and excitation wavelength = 557 nm. The regression equation is AF=I8.30 C＋119.5 （unit of C is lag/mL）, the correlation coefficient r =0.9810, and the detenrtination limit is 0.0052 p.g/mL. The method is applied to the determination of iodate ion in table salt and the results are satisfied.