水中无机砷原子荧光法与原子吸收法测定比较分析

Detection of inorganic arsenic in water with atomic fluorescence spectrometry and atomic absorption spectrometry:a comparison analysis

目的通过比较低压高效液相色谱-氢化物发生-原子荧光测定法(HPLC-HG-AFS)与氢化物发生-冷阱捕获-原子吸收测定法(HG-cold trap-AAS)对同一样品中无机砷的测试结果,分析原子荧光法在水中无机砷(i As)检测方面的适应性。方法分别对这2种检测方法进行准确度、精密度、检出限及线性范围等指标的检测,然后利用SPSS 19.0数据处理软件进行统计学处理与分析。结果原子荧光法与原子吸收法测得的线性相关系数均大于0.990,且原子荧光法的线性范围远大于原子吸收法;两种方法的检出限差异不明显;两种方法所得的精密度均小于10%;原子荧光法与原子吸收法对同一样品回收率经统计学分析,差异无统计学意义(t=–1.034,P=0.336)。结论低压高效液相色谱-氢化物发生-原子荧光测定法的线性范围更宽,能将各种价态砷进行有效的分离,而其他指标与氢化物发生-冷阱捕获-原子吸收测定法相比差异不明显。

Objective To compare detection results of inorganic arsenic （iAs） in the water samples with low-pressure high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry （HPLC-HG-AFS） and hydride generation-cold trap-atomic absorption spectrometry （HG-cold trap-AAS） and to analyze the applicability of atomic fluorescence spectrometry in iAs detection in water samples.Methods The accuracy, precision, detection limit, linear range, and other indicators of the two detection methods were analyzed statistically using SPSS 19.0.Results The linear correlation coefficients of the AFS and AAS were all greater than 0.99. The linear range of AFS detection was much wider than that of AAS; while no significant difference was observed in detection limit between the two methods. The precision of the two detection methods was less than 10%. The recovery rates of the two detection methods for same samples were not significantly different （t = -1.034, P = 0.336）.Conclusion Low-pressure HPLC-HG-AFS could be used in effective detection of iAs of various valences due to its wider detection linear range compared to HG-cold trap-AAS; no other significant differences between the two methods exist for the detection of iAs in water samples.