Based on gradient elution method, ion chromatography (IC) with the hydrophobic column AS-15 was developed to simultaneously determine the content of inorganic anions (I.e., F-, Cl-, NO3-, PO43-, SO42-, BrO3-, Br- and NO2-) in tea. Firstly, the tea powders were soaking in boiling water for 5 min at the ratio of tea to water as 1:50. Then, the powders were filtered out, and the filtrate was stabilized for 30 min. The prepared solution was treated by activated carbon cartridge, and the collected solution was filtered through a 0.20 u,m filter membrane before injection. The results showed that the 8 inorganic anions were thoroughly separated, the contents of anions and peak areas gave a good linear relationship, the detection limit was less than 0.056 mg/L, and their recoveries in the range from 96.5% to 105.1%. The established method is robust, and it can be used for the routine determination of inorganic anions with sound repeatability.%建立了一种利用强疏水性分离柱,通过KOH梯度淋洗,同时测定茶叶中F-、Cl-、NO3-、PO43-、SO42-、BrO3-、Br-、NO2-的方法.采用沸水冲泡茶样,茶水比为1∶50,时间为5min,过滤后稳定30min待测；样液经过活性炭净化,再用0.20 μm滤膜过滤后待测.结果表明:8种无机阴离子色谱峰能达到完全的基线分离,且浓度与峰面积呈良好的线性关系,检出限均低于0.056 mg/L,加标回收率为96.5％～105.1％,该法用于茶样中8种无机阴离子含量的测定,结果稳定且重复性较好.
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