微波辅助萃取-HPLC-AFS联用技术检测土壤样品中砷的化学形态

Speciation Analysis and Monitoring of Arsenic in Soil Samples by Microwave Assisted Extraction Coupled with High Performance Liquid Chromatography-Hydride Generation-Atomic Fluorescence Spectrometry

建立了微波辅助萃取-高效液相色谱（HPLC）-原子荧光光谱（AFS）联用技术分析土壤中亚砷酸盐[As（Ⅲ）]、二甲基砷（ DMA）、一甲基砷（ MMA）和砷酸盐[ As（Ⅴ）]等4种形态砷。用正交实验设计优化了功率、萃取溶剂体积、萃取温度、萃取时间等微波萃取条件。方法的线性范围为1.00～100μg/L，As（Ⅲ）、DMA、MMA 和As（Ⅴ）的检出限分别为0.21、0.33、0.38、0.56μg/L，相对标准偏差为4.6％～5.5％，样品回收率为78.1％～94.4％。用该法分析了4种土壤样品中的砷形态。

A method for determination of four arsenic species in soil samples was established by microwave assisted extraction （ MAE） coupled with high performance liquid chromatography （ HPLC）-hydride generation （ HG）-atomic fluorescence spectrophotometry （ AFS） . The MAE operating conditions were optimized by the orthogonal test design. The linear range of the calibration curve for As （ Ⅲ） , methyl arsenic acid （ MAA） , dimethyl arsenic acid （ DMA） and As （Ⅴ） was 1.00-100 μg/L. The detection limits for them were 0.21,0.33,0.38,0.56 μg/L, respectively. The RSD was 4.6%-5.5%, and the recoveries were 78.1%-94.4%. The method was successfully applied to the extraction and determination of four arsenic species in soil samples from different regions.