简易回流湿法消解-原子荧光光谱法测定大米粉中汞

Determination of Mercury in Rice Flour by Atomic Fluorescence Spectrometry

建立简易回流消解—原子荧光光谱法测定大米粉中汞,使用质控样对样品消解时间、酸用量、消解温度进行优化。实验结果发现:混酸用量10 mL、消解温度130℃、消解时间2.5 h,为最优前处理条件。该条件下,大米粉中汞检出限为0.065 mg/kg;浓度范围在0~1.0 ng/mL内线性关系良好(R^2=0.9999);质控样回平均收率为92.76%,相对标准偏差(RSD)为6.89%。该方法符合相关技术指标能满足测定要求,可用于大米粉中汞的测定。

Atomic fluorescence spectrometry was established for the determination of mercury in rice flour.Quality control sample was used to optimize digestion time,acid content and digestion temperature.The results found:10 m L mixed acid dosage,digestion temperature 130℃,digestion time 2.5 h,as the optimal pretreatment conditions.Under this condition,the detection limit of mercury in rice flour is 0.065 mg/kg.The concentration range was 0~1.0 ng/mL,and the linear relationship was good(R^2=0.9999).The average yield of quality control sample was 92.76%and the relative standard deviation(RSD)was 6.89%.The method can be used for the deter-mination of mercury in rice flour.