火焰原子吸收法测定特殊医用配方食品中钾钠的干扰及消除

Interference in the determination of potassium and sodium in foods for special medical prescription by flame atomic absorption and elimination

摘要: 研究了特殊医学用途配方食品中钾钠的测定,发现用火焰原子吸收法测定产生严重干扰,结果偏高,加入0.15%消电离剂氯化铯或0.05%氯化锶后可予以消除,其测钾线性范围0.50³.00μg/mL,回归方程y=0.0092+0.1794x,相关系数r=0.9996,检测限0.03μg/mL;测钠则分别为0.40¹.40μg/mL,y=0.1019+0.4592x,r=0.9991和0.01μg/mL;重复性好,钾RSD为4.10%,钠3.81%;回收率高,钾94.74%¹07.89%,钠95.33%¹06.66%,提高了测定的精密度和准确度。

Abstract: The studies of determination of potassium and sodium in food for special medical purposes showed that there were serious interferences, and results false increased.The interferences were eliminated by using ionization suppressant such as 0.15% cesium chloride or 0.05% strontium chloride solution.The linear range of potassium and sodium were 0.50 ~ 3.00 and 0.40 ~ 1.40μg /mL, the linear regression equation of potassium and sodium were y = 0.0092 + 0.1794x and y = 0.1019 + 0.4592x, the correlation coefficient of potassium and sodium were r = 0.9996 and r = 0.9991, the detection limit of potassium and sodium were 0.03 and 0.01μg /mL.This method showed good repeatability, the RSD of potassium and sodium were 4.10% and 3.81%, and high recovery rate potassium and sodium were 94.74% to 107.89% and 95.33% to 106.66%, respectively.This method improved precise and accuracy for the quantitative determination.