柱后衍生-液相色谱法测定食品接触纸制品中六价铬

Determination of hexavalent chromium in food contact paper products by liquid chromatography with post-column derivation

建立柱后衍生-液相色谱法测定食品接触纸制品中六价铬残留量的方法。试样用磷酸盐缓冲液萃取后进行过滤,以硝酸铵为流动相,经过AS 7阴离子交换柱进行分离,分离后的六价铬与衍生试剂(1,5-二苯碳酰二肼)在酸性条件下进行衍生化反应,采用紫外检测器在540 nm处进行检测。六价铬质量浓度在5~500μg/L的范围内与色谱峰面积线性关系良好,相关系数大于0.999,方法检出限为0.91μg/L。样品加标回收率为87.3%~96.1%,测定结果的相对标准偏差为4.14%~8.48%(n=7)。该方法选择性高,重复性好,设备简单,能满足食品接触纸制品中六价铬含量的测试要求。

A method for the determination of hexavalent chromium in food contact paper products by liquid chromatography with post-column derivatization was established.The samples were extracted with phosphate buffer and then filtered,separated by AS 7 anion exchange column with ammonium nitrate as mobile phase.The separated hexavalent chromium was derivatized with derivative reagent(1,5-diphenylcarbazide)under acidic condition,and detected at 540 nm by UV detector.The mass concentration of hexavalent chromium had good linear relations with the chromatographic peak area in the range of 5–500μg/L,the correlation coefficient was more than 0.999.The detection limit was 0.91μg/L.The recoveries were 87.3%–96.1%,and the relative standard deviations of determination results were 4.14%–8.48%(n=7).The method has the advantages of high selectivity,good repeatability and simple equipment,which can meet the requirements of determination of hexavalent chromium in food contact paper products.