离子色谱法测定食品中二氧化硫的应用研究

目的建立一种简便快速测定食品中二氧化硫残留量的离子色谱检测方法。方法选用瑞士万通861双抑制型离子色谱仪,Metrosep A Supp 4-250分析柱,3.1 mmol/L Na2CO3-1.0 mmol/L NaHCO3淋洗液,电导检测器检测,样品粉碎经蒸馏后,二氧化硫经3%双氧水氧化成硫酸根后测定。结果二氧化硫含量在0～266.76 mg/kg线性范围良好,线性回归方程y=10.126x+0.232,相关系数r=0.999 7,回收率为91.61%～98.41%,相对标准偏差(RSD)均小于5%,最低检出限为0.067 mg/kg。结论方法简便,精密度、重现性良好,准确度较高。

Ion chromatography in the detection of sulfur dioxide in foods

Objective To establish a simple and rapid method for the detection of sulfur dioxide residues in foods by ion chromatography.Methods Selecting a Metrohm 861 pairs of suppressed ion chromatography,a Metrosep A Supp.4-250 analytical column,eluted by 3.1mmol/L Na2CO3-1.0mmol/L NaHCO3,and using a conductivity detector.After the sample being crushed,sulfur dioxide in the sample was distilled and oxidized by 3% hydrogen peroxide to sulfate,and determined by ion chromatography.Results A good linear relationship was observed in the range of 0-266.76 mg/kg,the linear regression equation was y=10.126 x + 0.232,correlation coefficient(r) was 0.999 7,the recovery was in the range of 91.61%-98.41%,the relative standard deviation(RSD) was less than 5%,the detection limit of the method was 0.067 mg/kg.Conclusion The ion chromatography method in the detection of sulfur dioxide in foods is simple,precise,strong reproducible and accurate.