液相色谱-原子荧光法测定大米中4种砷形态

Determination of 4 kinds of arsenic species in rice by liquid chromatography- atomic fluorescence spectrometry

中文关键词:  大米  砷形态  超声提取  液相色谱-原子荧光法  硝酸

英文关键词:rice  arsenic species  ultrasonic extraction  liquid chromatography-atomic fluorescence spectrometry  nitric acid

中文摘要:

      目的 建立以0.3 mol/L硝酸为提取剂提取大米中4种砷形态(亚砷酸根As III、砷酸根As V、一甲基砷MMA和二甲基砷DMA)的液相色谱-原子荧光(liquid chromatography-atomic fluorescence spectrometry, LC-AFS)分析方法。方法 在60 ℃条件下, 超声40 min提取大米样品, 上清液供 LC-AFS 测。比较2种提取方法对稻米中4种砷形态的提取效率, 并对提取温度和提取时间等条件进行优化。结果 4种砷形态化合物的检出限为0.002~0.01 μg/mL, 加标回收率为89.03%~100.70%, RSD不大于4.36%(n=5)。结论 此方法可以在1 h时内完全分离大米样品中的四种砷形态, 操作简单、灵敏, 适用于大米中重金属砷的风险评估。

英文摘要:

      Objective Using 0.3 mol/L nitric acid as the extractant, to establish a method for the simultaneous determination of arsenious acid (As III), arsenic acid (As V), dimethylarsinic acid (DMA) and monomethylarsinic acid (MMA) in rice by liquid chromatography-atomic fluorescence spectrometry (LC-AFS). Methods After ultrasonic extraction 40 min at 60 ℃, the sample was detected by LC-AFS. The extraction efficiency of two kinds of extracted methods was compared. The concentration of nitric acid, extraction temperature and extraction time were optimized. Results The detection limits of 4 kinds of main arsenic species ( As III, As V, DMA, MMA ) in rice were 0.002~0.01 μg/mL, the recoveries were in the range of 89.03%~100.70%, and the relative standard deviations (RSDs) were less than 4.36%(n=5). Conclusion This method can completely separate the 4 kinds of arsenic species in rice samples within 1 h, which is simple, accurate for the risk assessment of heavy metal arsenic in rice.