超声辅助热水提取-离子色谱法同时测定蔬菜中的硫氰酸盐和高氯酸盐

Simultaneous Determination of Thiocyanate and Perchlorate in Vegetables by Ultrasonic Assisted Extraction of Hot Water-Ion Chromatography

建立同时测定蔬菜中硫氰酸盐和高氯酸盐的离子色谱分析方法。样品采用纯水超声辅助提取,离心后直接过膜的前处理技术,然后采用IonPac AS16离子分析柱进行分离,电导检测器进行检测,KOH溶液梯度洗脱,通过外标法定量。结果表明,硫氰酸盐和高氯酸盐分别在0.2～5.0和0.04～1.00 mg/L范围内具有良好的线性关系,相关系数分别为0.9997和0.9989,检出限分别为0.005、0.008 mg/L,方法回收率分别为89.9%～98.4%和81.2%～94.4%,重复性实验的相对标准偏差分别为1.6%和6.9%。实际样品测定中,8类蔬菜样品全检出一定量的硫氰酸盐和高氯酸盐,其中胡萝卜干的硫氰酸盐和高氯酸盐最高。

A method was developed to determine thiocyanate and perchlorate in vegetables.The sample was extracted by ultrasonic assisted with ultrapure water and filtered after centrifugation as pre-treatment technology.Then the samples were separated with an IonPac AS16 anion analysis column by gradient elution with KOH solution,detected by conductivity detector,and quantified by external standard method.The results showed that,the calibration curve of thiocyanate and perchlorate was linear in the range of 0.2~5.0 mg/L and 0.04~1.00 mg/L with correlation coefficients of 0.9997 and 0.9989,respectively.The limits of quantitation were 0.005,0.008 mg/L,respectively.The recoveries were in the range of 89.9%~98.4%and 81.2%~94.4%,and relative standard deviations repeatability test were 1.6%and 6.9%,respectively.In the result,vegetable samples all contained a certain amount of thiocyanate and perchlorate,and the highest content of carrots dry.