火焰原子吸收法测定钠元素分析条件的优化

Optimization of analytical conditions of determination of sodium by flame atomic absorption spectrometry

中文关键词:  火焰原子吸收光谱法  钠  正交试验  优化

英文关键词:flame atomic absorption spectrometry  sodium  orthogonal test  optimization

中文摘要:

      目的 探讨火焰原子吸收光谱法测定钠元素的最佳工作条件。方法 对仪器元素灯的灯电流、狭缝宽度、压缩空气流量、燃气/助燃气比等参数进行正交试验优化, 确定最佳的测定条件。结果 最佳工作条件为: 元素灯电流4.0 mA; 压缩空气流量140 kPa; 燃气/助燃气比1:7; 狭缝0.4 nm; 钠元素在1.0~5.0 mg/L范围内线性关系良好(r=0.9996), 具有良好精密度(RSD=0.54%), 在浓度1.0、3.0和6.0 mg/L添加水平下, 钠加标回收率分别为98.09%、101.63%和99.49%。结论 经优化分析解决了高浓度标准曲线向下弯曲的问题, 扩宽了线性范围, 提高了检测结果准确性, 能满足食品中钠元素的实际检测需要。

英文摘要:

      Objective To explore the optimum working conditions for the determination of sodium element by flame atomic absorption spectrometry. Methods The orthogonal test was conducted using instrument lamp, slit width, compressed air flow, and fuel gas/oxidant gas ratio as considering parameters, to determine the best measurement conditions. Results The optimum working conditions were as follows: element lamp current was 4.0 mA, compressed air flow was 140 kPa, fuel gas/oxidant gas ratio was 1:7, slit width was 0.4 nm. Under the optimum working solution, sodium element had a good linear relationship in the range of 1.0~5.0 mg/L(r=0.9996) with good precision (RSD=0.54%). The recoveries of sodium element spiked at 1.0, 3.0 and 6.00 mg/L were 98.09%, 101.63% and 99.49%, respectively. Conclusion The analysis and optimization solve the problem of high-concentration standard curve downward bending, widen the linear range and improve the detection accuracy of the results, which can meet the demand of routine analysis of sodium in food.