稻米中无机砷的提取与测定

通过与无机砷的2种国标提取方法的实验对比,建立高效、快速的微波辅助提取稻米中无机砷的方法,以0.3mol/L盐酸为提取剂,在60℃、固液比1:20的条件下微波加热提取15min,并用1%的L-半胱氨酸完成对As(V)的预还原。方法回收率为As(Ⅲ):94%～108%、As(V):92%～101%,精密度为2.94%,检出限为0.086μg/L,可准确用于稻米中有毒无机砷的定量检测和风险评估。

The extraction and determination of inorganic arsenic in rice

An efficient and rapid microwave-assisted extraction method of in organic arsenic in rice was established.The process was:0.3mol/L hydrochloric acid serves as extracting agent,under T=60℃,solid-liquid ratio was 1:20,microwave-assisted extraction for 15min,As(V) was reduced by 1% L-cysteine.By this process,recovery rate of As(Ⅲ) and As(V) were 94%~108% and 92%～101%,respectively,precision bias was 2.94% and the detection limit was 0.086μg/L.This process might apply accurately in quantitative detection and risk evaluation of toxic inorganic arsenic in rice.