高效液相色谱法测定纸质食品包装材料中的荧光增白剂

目的使用高效液相色谱法检测云南省纸质食品包装材料11种荧光增白剂的添加情况。方法样品采集自云南省16个州市118份纸质包装材料,粉碎后经用40%乙腈-水超声提取3次,合并提取液,离心,上清液经正己烷脱脂。脱脂后的溶液在C_(18)色谱柱上,用带有离子对试剂的流动相梯度洗脱分离后,采用紫外检测,外标法定量。结果本方法在22 min内完成11种目标化合物的分离分析,线性关系良好,相关系数(R~2)均大于0.99。在低、中和高3个添加水平的回收率为85.1%～104.6%,相对标准偏差(relative standard deviations,RSDs)小于8.2%(n=6),方法定量限(limits of quantitation,LOQ)为3.2～6.0 mg/kg,阳性样品检出率达到7.62%,含量最高达38.6 mg/kg。结论云南省纸制品存在添加荧光增白剂,部分样品中检测出多种荧光增白剂非法添加,相关部门应该予以重视,加强对纸质食品包装材料的监督管理。

Determination of fluorescent whitening agents in food packaging paper materials by high performance liquid chromatography

Objective To investigate the contamination of 11 kinds of fluorescent whitening agents in food packaging paper materials in Yunnan province by high performance liquid chromatography (HPLC). Methods The 118 food packaging paper materials were collected from the market in 16 areas of Yunnan province. The crushed samples were extracted by 40% acetonitrile-water for 3 times and centrifugated. Then the supernatant was defatted by n-hexane. After degreasing, the solution was separated on a C18 column by gradient elution with an ion pair reagent and UV detection. The external standard method was used. Results The separation and analysis of 11 target compounds were achieved within 22 min, and the correlation coefficients (R2) were more than 0.99. The recoveries were ranged from 85.1% to 104.6% for 11 kinds of fluorescent whitening agents with 3 spiked levels of low, middle and high concentrations. The relative standard deviations (RSDs) were less than 8.2% (n=6), and the limits of quantitation (LOQ) for the 11 kinds of fluorescent whitening agents were 3.2~6.0 mg/kg. The detection rate of positive samples reached 7.62% and the highest content was 38.6 mg/kg. Conclusion Fluorescent whitening agents still exist in paper products in Yunnan province, and a variety of fluorescent whitening agents illegally added in some samples are detected. The relevant supervision should give more attention and strengthen the monitoring of food packaging paper materials.