管式湿法消解氢化物发生-原子荧光法测定尿中砷

目的建立一种采用管式湿法消解氢化物发生-原子荧光法测定尿中砷的测定方法。方法尿样经0.25 ml硝酸(1∶1)、0.5 ml过氧化氢(30%)和0.1 ml硫酸(1∶1)在AED-Ⅵ型管式自控电热消化器上加热消解后,以5%的盐酸溶液作为反应介质和载流,2%的硼氢化钾溶液作为还原剂,用AFS-9730双道原子荧光光度计测定砷含量。结果本方法标准曲线线性范围为0μg/L^100μg/L、最低检出限为0.8μg/L、RSD为2.31%~5.36%、回收率范围94.2%~104.0%,总平均回收率98.8%。测定2018年和2019年含砷冻干尿样,Z分值分别为0.50和-0.01、0.33和0.62,结果全部合格。用本方法与WS/T 474-2015方法同时测定20份尿样的结果比较,差异无统计学意义(P>0.05)。结论本方法具有线性范围宽、灵敏度高、准确度和精密度好、操作简便和节约环保,适宜推广和应用。

Determination of arsenic in urine bytest-tube wet digestion hydride generation atomic fluorescence spectrometry

Objective To establish a method for determination of arsenic in urine by test-tube wet digestion hydride generation atomic fluorescence spectrometry.Methods The urine samples were digested by 0.25 ml nitric acid(1∶1),0.5 ml hydrogen peroxide(30%)and 0.1 ml sulfuric acid(1∶1)in the AED-VItube type automatic control electrothermal digestion instrument digester.The arsenic content was determined byAFS-9730 double channel atomic fluorescence spectrometer with 5%hydrochloric acid solution as reaction medium and carrier current,2%potassium borohydride solution as reducing agent.Results The linear range of the standard curve of this method is 0 g/L to 100 g/L,the minimum detection limit is 0.8 g/L,the RSD is 2.31%to 5.36%,the recovery range is 94.2%to 104.0%,and the total average recovery is 98.8%.Determination of lyophilized urine samples containing arsenic in 2018 and 2019,with Z scores of 0.50 and-0.01,0.33 and 0.62,and all the results were qualified.This methodand standard for WS/T 474-2015 method wereused todeterminate 20 urine samples,results ofthe two methodswere notsignificanty different(P>0.05).Conclusion The method has wide linear range,high sensitivity,good accuracy and precision,simple operation,environmental protection,and is suitable for promotion and application.