超声辅助提取-高相液相色谱-电感耦合等离子体质谱法测定香菇中6种形态砷化合物

建立一种同时测定香菇中6 种形态砷化合物（亚砷酸根、砷酸根、一甲基砷酸、二甲基砷酸、砷甜菜碱、砷胆碱）的超声辅助提取-高效液相色谱-电感耦合等离子体质谱（high performance liquid chromatography-inductivelycoupled plasma mass spectrometry，HPLC-ICP-MS）分析方法。选取0.3 mol/L乙酸溶液作为提取剂，超声辅助提取香菇样品中的砷化合物，选用Hamilton PRP X-100阴离子交换柱，25 mmol/L磷酸二氢铵和水作为流动相进行梯度洗脱，经HPLC-ICP-MS进行分离和定量分析。结果表明，在优化实验条件下，6 种形态砷化合物在0～50 μg/L范围内线性良好，相关系数R2均在0.998 0以上，检出限为0.31～0.59 μg/L，相对标准偏差为1.6%～3.7%，加标回收率在94.30%～102.75%之间。4 种处理方式后的香菇样品的测定结果显示，无机砷是主要的砷化合物，占总砷含量的48.68%～64.25%。方法灵敏度高，前处理简单高效，可以有效地分析香菇样品中不同形态的砷化合物。

Arsenic Speciation Analysis of Lentinus edodes by Ultrasonic-Assisted Extraction-High Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry

The speciation of arsenic in Lentinus edodes was analyzed using ultrasonic-assisted extraction (UAE) combined with high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS). Six arsenic compounds were extracted ultrasonically from the samples using 0.3 mol/L acetic acid solution as extraction solvent. The chromatographic separation was performed on a Hamiton PRP-X100 anion exchange column using a mixture of 25 mmol/L ammonium dihydrogen phosphate and water as the mobile phase. Under the optimized conditions, there were good linear relationships in the range of 0–50 μg/L for six arsenic compounds, with correlation coefficients all above 0.998 0. The limit of detection (LODs) of six arsenic species (AsC, AsB, DMA, MMA, AsIII, and AsV) were between 0.31 and 0.59 μg/L. The precision of the method, expressed as relative standard deviation (RSD), was less than 5%. The recoveries of AsC, AsB, AsIII, DMA, MMA, and AsV were in the range of 94.30%–102.75%. Speciation analysis could accurately determine six arsenic species in L. edodes. Inorganic arsenic was the main species in L. edodes, which was in the range of 48.68%–64.25%. This method was simple, rapid, sensitive and accurate, and could meet the requirements for the quantitative analysis of arsenic speciation in plant materials.