微波消解电感耦合等离子体-质谱法测定面粉中的铝

面粉样品经微波消解后,以⁴⁵Sc为内标元素校准基体效应及信号漂移,用电感耦合等离子体.质谱法直接测定,外标法绘制校准曲线进行定量。测定面粉中铝的检出限为0.25mg/kg,线性良好,相关系数r=0.9999,相对标准偏差1.25%—3.03%,加标回收率在93.9%—103.5%之间。该方法灵敏快速,干扰小,重现性好,能满足面粉中铝含量测定的要求。

Determination of Aluminum in Flour by Inductively Coupled Plasma-Mass Spectrometry with Microwave Digestion

The determination of the content of aluminum in flour was established by inductively coupled plasma-mass spectrometry（ICP-MS） with microwave digestion.After microwave digestion, the samples were directly analyzed by ICP-MS for determination of aluminum with ⁴⁵Sc as the internal standard for calibration matrix effect and signal drift.External calibration was applied to making calibration curve for quantitative detection.The detection limit of aluminum in flour was 0.25mg/kg with good linear correlation（r= 0.9999）.The relative standard deviation was 1.25%—3.03%,and the recovery was between 93.9%and 103.5%.This method is proved to be sensitive,rapid and reproducible with low interference,and can be applied to the analysis of content of aluminum in flour with satisfactory results.