摘要
Abstract
Objective:To establish the method of determination of cadmium in rice by direct dilution injec-tion graphite furnace atomic absorption spectrometry.Methods:Crushed rice was diluted by mixture of 0.5% nitric acid and 0.1% Triton.Then the diluent was well shaken for further test.NH4 H2 PO4 +Mg (NO3 )2 were chosen as the matrix modifier,while the Zeeman effect background deduction method was a-dopted.The samples were subjected to one -step ashing method(argon),and two -step ashing method (argon +air),respectively,to create external standard calibration curves.The standard addition method was used to determine cadmium content in rice.The results showed that the RSD(N =6)of three methods were 1.78%,3.29%,and 0.62%,while the recovery rates were 114.7%,103.9%,and 102.5%.The detection limits were 0.025,0.031,and 0.035 μg/L.After T test of pairwise comparison,no significant difference was shown between two -step ashing method and standard addition method,and the accuracy and precision meet the requirements for determination well.Conclusion:As a simple,rapid and non -pol-luting method,the direct dilution injection graphite furnace atomic absorption spectrometry can be used for the determination of cadmium content in rice precisely and accurately.关键词
石墨炉原子吸收/大米/直接稀释进样/镉Key words
Graphite furnace atomic absorption/rice/direct dilution sampling/Cadmium分类
轻工纺织
