火焰原子吸收光谱法测定食品中铁的方法学验证

Methodological Verification for Determination of Iron in Food by Flame Atomic Absorption Spectrometry

以小麦粉、苹果、固体饮料3种食品为基质对GB 5009.90—2016《食品安全国家标准食品中铁的测定》第一法火焰原子吸收光谱法进行方法学验证。对线性范围、检出限、正确度、精密度分别进行验证,正确度、精密度分别用方法回收率、实验室内变异系数(C.V.)表示。结果表明:校准曲线在0~6 mg/L范围内线性良好,线性回归方程相关系数r=0.999 1;小麦粉、苹果、固体饮料检出限均为0.5 mg/kg;方法回收率范围96.0%~100.2%;实验室内变异系数(C.V.)范围0.20%~6.5%。各验证结果均满足GB/T 27417—2017《合格评定化学分析方法确认和验证指南》相关要求。该方法在该实验室可用。

Using wheat flour, apple and powder drinks as the substrates, the first method of flame atomic absorption spectrometry in GB 5009.90—2016 Food Safety National Standard Determination of Iron in Food was verified. The linearity of calibration, detection limit, trueness and precision were verified;Trueness and precision were expressed by method recovery and coefficient of variation(C.V.) in the laboratory. The results showed that the calibration curve gave a good linearity in the range of 0-6 mg/L and the correlation coefficient of linear regression equation was 0.999 1;The detection limits of wheat flour, apple and powder drinks were all 0.5 mg/kg;The method recovery rates ranged from 96.0% to 100.2%;The coefficient of variation(C.V.) in the laboratory ranged from 0.20% to 6.5%. All the verification results met the requirements of GB/T 27417—2017 Comformity Assessment Guidance on Validation And Verification of Chemical Analytical Methods. This method was available in the laboratory.