高分辨连续光源石墨炉原子吸收光谱法测定面制食品中的铝

Determination of Aluminum in Wheat Flour Food by Microwave Digestion-High Resolution Continuum Source Graphite Furnace Atomic Absorption Spectrometry

使用微波消解-高分辨连续光源石墨炉原子吸收光谱法测定四种面制食品(挂面、饺子皮、油条和梳打饼干)中铝的含量。样品置于密闭聚四氟乙烯消解罐中经HNO3和H2O2混合溶液完全消解。对微波消解条件、灰化温度和原子化温度进行了优化。确定最佳实验条件为:消解液HNO3和H2O2体积比7∶1,微波功率1 000W,190℃消解40min;最佳灰化温度1 350℃;最佳原子化温度2 400℃;基体改进剂为1g.L-1硝酸镁。标准曲线相关系数为0.999 9,相对标准偏差(RSD)1.7%～2.4%,回收率98.16%～102.67%。本研究建立的面制食品中铝含量的测定方法对于相关食品标准检测方法的制定具有参考价值。

The contents of aluminum（Al）in four kinds of wheat flour food（noodle,dumpling wrapper,twisted cruller and sodabiscuit）were determined by high resolution continuum source graphite furnace atomic absorption spectrometry（HR-CS GFAAS）combined with microwave digestion.The samples were completely digested by the mixture of HNO3and H2O2in closed polytet-rafluoroethylene（PTFE）vessels.The conditions for microwave digestion,pyrolysis temperature and atomization temperaturewere optimized.The optimum experimental conditions were determined as follows.The microwave digestion was performed withHNO3/H2O27∶1（volume ratio）,microwave power 1 000Wand 190℃for 40minutes.The optimum pyrolysis temperaturewas 1 350℃and the optimum atomization temperature was 2 400℃.Magnesium nitrate solution with the concentration of 1g.L-1 was used as the matrix modifier.The correlation coefficient for the standard curve was 0.9999,the relative standard devia-tion（RSD）was from 1.7%to 2.4%,and the recovery for the samples was from 98.16%to 102.67%.The assay method forthe determination of Al in wheat flour food established in this study has referential importance for the constituent of the correla-ted food standards.