反相离子对高效液相色谱法测定微量碘的研究

Determination of Micro Amounts of Iodine by Reversed-phase Ion-pair HPLC

建立了一种反相离子对高效液相色谱测定微量碘的新方法。采用WatersSpherisorbODS2(5μm ,4.6mmi.d.×250mm)色谱柱 ,以甲醇 -水 (体积比为30∶70)作为流动相 ,四丁基溴化铵 (TBA·Br)作离子对试剂 ,流速为1.0mL/min,在223nm处检测 ,将I- 与在紫外区有吸收的共存离子完全分离。I- 的质量浓度在0.20～180μg/mL范围内 ,峰面积Y与质量浓度X(μg/mL)呈良好的线性关系 ,r=0.9997 ,I -的检出限为53.2μg/L。该方法已用于海水和海带、紫菜等食品中碘含量的测定 ,加标回收率为98%～101 % ,相对标准偏差为1.04 %～3.01 %。

A newmethod for the determination of iodine by reversed_phase ion_pair HPLC has been develˉoped.Iodides can be successfully separated from other coexisting anions that absorb ultraviolet rays on an ODS2column(4.6mm i.d.×250mm,5μm)by using methanol-water(volume ratio30∶70)as the mobile phase and3mmol/L tetrabutylammonium bromide(TBA·Br)as the ion_pair reagent.The flow rate was set at1.0mL/min and the detection wavelength was223nm.The iodide peak area Yshows a linear correlation with the iodide mass concentration X in the range of0.20～180μg/mL with a correlaˉtion coefficient of0.9997.The detection limit for iodide is53.2μg/L.The method has already been used for the determination of iodides in seawater and seafood,such as kelp and laver.The recoveries of the added standard were found to be98%～101%with relative standard deviations of1.04%～3.01%.