超级微波消解—电感耦合等离子体质谱法测定豆奶粉中镍的含量

Determination of nickel in soy milk powder by ultra-wave digestion-inductively coupled plasma mass spectrometry

目的:为市售豆奶粉中镍污染风险防控提供技术支撑。方法:以浓硝酸为消解液,利用超级微波消解进行前处理,以铑元素作为内标物消除基质干扰,在动能甄别模式(KED)下利用电感耦合等离子体质谱法测定豆奶粉中镍元素的含量,并对超级微波消解条件与ICP-MS工作条件进行了优化。结果:该方法的标准曲线在0~10μg/L的质量浓度范围内线性关系良好,相关系数为0.9999,检出限为0.002 mg/kg,加标回收率为94.5%~100.6%,相对标准偏差为1.8%~2.3%;用豆奶粉中镍质控样(ZKQC5210)对该方法进行准确性验证,结果在证书标定范围内。结论:该方法准确可靠,适用于豆奶粉中镍含量的测定。

Objective:This study aimed to provides technical support for the risk prevention and control of nickel contamination in market soy milk powder.Methods:With concentrated nitric acid as digestion solution,the ultra-wave digestion was utilized for preprocessing,and then the ICP-MS,with Rhodium as internal standard to eliminate matrix interference and in the KED mode,was used to determine the content of nickel in soybean milk powder.Moreover,the conditions for ultra-wave digestion and ICP-MS were also optimized.Results:The linear relationship of the standard curves was located within the mass concentration of 0~10μg/L,with correlation coefficient of 0.9999,and the detection limit was 0.002 mg/kg.The recovery percent ranged form 94.5% to 100.6% and the relative standard deviation(RSD)was 1.8%~2.3%.The proposed method was validated on the quality control sample of soy milk powder(ZKQC5210)and the determination result was in the certification scope.Conclusion:The proposed method was correct and reliable,so it was suitable for the determination of the nickel content in soybean milk powder.