积分安培检测-离子排斥色谱法测定食品中亚硫酸盐的研究

Determination of sulfite in food by ion exclusion chromatography with integrated amperometric detection

目的：建立积分安培检测-离子排斥色谱法测定食品中亚硫酸盐的方法。方法：采用ICE-AS1型离子排斥分离柱（9×250 nm）,10 mmol/L H2SO4淋洗液,样品经10 mmol甘露醇＋20 mmol Na2HPO4缓冲液浸泡提取。过滤后进样积分安培检测分析。结果：方法线性好,相关系数r=0.9999,相对标准偏差RSD〈3.5%,样品加标回收率在87.88%-101.79%,方法检出限为0.85 mg/kg。结论：该方法样品前处理简单,测定结果准确,重现性好,对分析测定食品中亚硫酸盐具有实用意义。

Objective：To establish a method of ion exclusion chromatography with integrated amperometric detection for the determination of sulfite in food.Methods：Sulfite was separated from other matrix components by ion exclusion chrmatography using a sulfuric acid eluent and detected by integrated amperometry using a platinum working electrode.An anion exclusion column ICE-AS1（9×250） was used for the separation of sulfite.10 mmol/L H2SO4 was eluent.Food samples were prepared by homogenization in the buffer（20 mmol Na2HPO4/10 mmol Mannitol,pH 9）,followed by filtration.Liquid samples were diluted in the buffer prior to injection.Results：This method had a good linear relationship（r=0.9999）.Good method performance was shown,with injection-to-injection repeatability less than 3.5%.The spike recovery rate in samples was 87.88%～101.79% and the method detection limit was 0.85 mg/kg.Conclusion：The method offers a substantial improvement in the detection of sulfite.It is adapt to determine the sulfite in food.