微波消解-原子荧光光谱法同时测定香辛料中砷、汞含量

Simultaneous determination of arsenic and mercury in spices by microwave digestion-atomic fluorescence spectrometry

中文关键词:  原子荧光光谱法  微波消解  香辛料  砷  汞

英文关键词:atomic fluorescence photometry  microwave digestion  spices  arsenic  mercury

中文摘要:

      目的 建立微波消解-原子荧光光谱法同时测定香辛料中砷、汞含量的方法。方法 样品加入硝酸和双氧水, 微波消解后加热浓缩, 冷却后加入硫脲与抗环血酸混合溶液, 加水定容, 使用原子荧光光谱仪进行测定。结果 砷和汞分别在0~20.0 μg/L和0~2.0 μg/L浓度范围与荧光强度呈良好的线性关系, 相关系数均大于0.9997。砷和汞的方法检出限分别为0.0026和0.0006 mg/kg; 精密度和重复性实验的相对标准偏差(relative standard deviations, RSD)小于5%; 加标回收率分别为93.2%和103.0%; 对国家标准物质(GBW 10020柑橘叶)检测结果均在标准认定值范围。结论 该法操作简单、检出限低、准确度高, 适合香辛料中砷、汞含量的检测。

英文摘要:

      Objective To establish a method for simultaneous determination of arsenic and mercury in spices by microwave digestion and atomic fluorescence spectrometry. Methods The sample was added with nitric acid and hydrogen peroxide. After microwave digestion, it was heated and concentrated. After cooling, thiourea and acid-resistant mixed solution were added, and constant volume by adding water. Results The concentrations of arsenic and mercury in 0-20.0 μg/L and 0-2.0 μg/L showed good linear relationships with fluorescence intensity, and the correlation coefficients were all greater than 0.9997. The detection limits of arsenic and mercury were 0.0026 and 0.0006 mg/kg, respectively. The relative standard deviation of precision and repeatability was less than 5%. The spiked recovery rates were 93.2% and 103.0%, respectively. The test results of national standard substance (GBW 10020 citrus leaf) were all within the standard value range. Conclusion The method is simple in operation, low in detection limit and high in accuracy, which is suitable for detecting the content of arsenic and mercury in spices.