衍生化-富集-表面增强拉曼光谱法快速筛查奶粉中亚硝酸盐

Rapid detection of nitrite in milk powder by derivatizationenrichment-surface enhanced Raman spectroscopy

目的建立衍生化-富集-表面增强拉曼光谱法快速检测奶粉中亚硝酸盐的分析方法。方法样品水溶液通过除蛋白、衍生化后,采用阳离子小柱PSY-001对衍生化合物进行富集,再使用表面增强拉曼光谱对样品中的亚硝酸盐含量进行定性检测。结果7类不同奶粉,采用本研究所建立的方法进行检测,根据不同的批处理量,单个样品检测全过程只需3~15min,定性检测限为0.4mg/kg,远低于国家安全标准对亚硝酸盐的限量要求(2 mg/kg)。方法的灵敏度在96%~100%,特异性为100%,假阴性率为0%~4%,假阳性率为0%,相对准确度为98%~100%。结论该方法操作简单、快速,易于掌握,适用于奶粉中亚硝酸盐的快速筛查。

Objective To eatablish a method for the rapid detection of nitrite in milk powder by derivatization-enrichment-surface enhanced Raman spectroscopy.Methods The aqueous solutions of samples were deproteinized and derivatized,and the derived compounds were enriched by cationic cartridge PSY-01,finally,the nitrite in samples were qualitative detected by surface enhanced Raman spectroscopy.Results Seven kinds of milk powders were tested by this method,which took only 3-15 minutes per sample,depending on batch processing capacity.The limits of detection(LOD)of this method was 0.4 mg/kg and much less than maximum residue limit(MRL)of nitrite specified in national food safety standard of China(2 mg/kg).The sensitivity of this method was 96%-100%,the specificity was 100%,the false negative rate was 0%-4%,the false positive rate was 0%,and the relative accuracy was 98%-100%.Conclusion This method is simple,quick and easy to operate,and therefore suitable for the rapid screening of nitrite in milk powder.