微提取—离子色谱法快速测定干红葡萄酒中亚硫酸盐

Rapid determination of sulfites by microextraction-ion chromatography in red wine

目的:结合离子色谱法的优势,对国标方法蒸馏前处理进行改进,建立一种快速测定干红葡萄酒中亚硫酸盐的微提取—离子色谱准确定量的检测方法。方法:样品通过微提取装置释放出二氧化硫,被氢氧化钠溶液吸收生成亚硫酸根,再将其氧化为硫酸根,经0.45μm滤膜过滤除杂后,用离子色谱仪进行测定。结果:亚硫酸根离子质量浓度为1.0~50 mg/L亚硫酸根浓度与其峰面积呈良好的线性关系,相关系数为0.9999,检出限为0.24 mg/L。添加不同水平硫酸盐加标回收率平均值为95.2%~99.1%,相对标准偏差(RSD)为6.84%~8.65%。结论:该方法的前处理操作简单、快速,杂质干扰明显减少,适合批量样品的检测。

Objective:In view of the improvement of the national standard method of distillation pretreatment,combined with the advantages of ion chromatography,a rapid determination of sulfite by microextract-ion chromatography in red wine was established.Methods:Sulfur dioxide was released by microextraction device,which was absorbed by sodium hydroxide solution to form sulfite,and then oxidized to sulfate.The samples were then filtered by 0.45μm filter and determined by ion chromatograph.Results:The concentration of sulfite ion in range of 1.0~50 mg/L showed a linear relationship with the peak area,with correlation coefficient of 0.9999,and the detection limit was 0.24 mg/L.The average recoveries of different levels of sulfate were 95.2%~99.1%,and the relative standard deviations(RSD)were 6.84%~8.65%.Conclusion:The method has the advantages of simple and fast pretreatment operation,reduced impurity interference significantly,and is suitable for the detection of batch samples.