火焰原子吸收法测定乳粉中的锰

Determination of manganese in milk powder by flame atomic absorption spectrometry

目的优化火焰原子吸收法测定乳粉中锰的分析方法。方法对火焰原子吸收分光光度计仪器的燃烧器高度、助燃比等仪器条件进行优化,确定最佳实验条件。结果最佳仪器条件:灯电流7.5 mA;狭缝宽度:0.2 nm;燃烧器高度10 mm;燃气流量:2.4 L/min,助燃气流量:15.0 L/min。在最佳仪器条件下乳粉中的锰0~3 mg/L范围内线性关系良好,相关系数在0.9995以上,检出限为0.0099 mg/kg、回收率为93.6%~99.5%,精密度为0.66%~3.49%。结论本方法具有灵敏度高、准确度高、精密度好等优点,适用于乳粉中锰的含量测定。

Objective To optimize the method for the determination of manganese in milk powder by flame atomic absorption spectrometry. Methods The burner height, combustion ratio and other instrumental conditions of flame atomic absorption spectrophotometer were optimized to determine the best experimental conditions. Results Best instrument conditions were as follows: lamp current was 7.5 mA, slit width was 0.2 nm, burner height was 10 mm, gas flow rate was 2.4 L/min, auxiliary gas flow rate was 15.0 L/min. Under the optimal instrument condition, manganese in milk had good linear relationships in the range of 0-3 mg/L, and the correlation coefficients were larger than or equal to 0.9995. The limit of detection was 0.0099 mg/kg. The recoveries were 93.6%-99.5%, with the relative standard deviations of 0.66%-3.49%. Conclusions This method has the advantages of high sensitivity, high accuracy and good precision, which is suitable for the determination of manganese in milk powder.