离子色谱法测定食品中亚硫酸盐的应用研究

Measurement of sulfite in food by ion chromatography

[目的 ]建立离子交换—电导检测离子色谱法测定食品中亚硫酸盐的检测方法。 [方法 ]选用lonPacAS9-SC分离柱 ,1.80mmol/LNa2 CO3 -1.70mmol/LNa2 HCO3 ,淋洗液 ,外接水自动再生 ,甲醛作SO2 -3 的稳定剂 ,样品经 10mmol/LNaOH溶液浸提后 ,过滤进样分析。 [结果 ]方法的相关性好 (r >0 .9990 ) ,标准及样品测定的相对标准偏差分别为RSD <1.74%、RSD <3 .91% ,样品的加标回收率 :89.2 %～ 10 8.8% ,检出限 0 .3 3mg/kg。与分光光度法作对比测定的结果表明 ,该方法的准确度高 ,适用性较好。 [结论 ]本方法线性范围广、测定结果准确、操作简便 ,对多种样品适应性好 ,结果令人满意。

睴bjective〕 An ionexchange method with conductingdetection was established to measure sulfite in food .〔Method〕 IonPac AS9-SC was selected as the seperation column,1.80mmol/L Na 2CO 3-1.70mmol/L NaHCO 3 was eluent,and the instrument auto-generated with outside-connected water.Formaldehyde was added into samples to stabilize sulfite.After diyested with 10mmol/L NaOH and filtrated with 0.45μm membrane ,the samples was injected and analysized.〔Results〕 It is showed that this method has a good relativity (r>0.9990);the RSD% of standards and samples were less than 1.74% and 3.91% respectively;the spike recovery rate in samples was between 89.2% and 108.8% and the method detection limit was 0.33mg/kg.Comparing with the resulths by spectrophotometry It showed this method has better accuracy and adaptility.〔Conclusion〕 In a word,this method has a wide linear range,accurate results,and a good adaptility to various samples.