摘要
用0.20g·L-1曲拉通X-100稀释液[内含0.20%(体积分数,下同)硝酸]制备牛奶样品溶液,直接进石墨炉原子吸收光谱仪中按照优化的仪器工作条件测定其中铅含量,在线加入0.20g·L-1硝酸钯溶液(基体改进剂)去除基质干扰。采用基质匹配标准溶液系列制作标准曲线,结果发现,铅的质量浓度分别在1.00~4.00μg·L-1和6.00~24.0μg·L-1内与其对应的吸光度呈线性关系,检出限(3s)为1.90μg·kg^(-1)。对牛奶样品进行4个浓度水平的加标回收试验,得到回收率为97.2%~102%,测定值的相对标准偏差(n=5)为1.5%~13%,满足国家标准GB/T27404-2008附录F的规定。按照此方法分析了8款牛奶样品,检出量均小于国家标准GB2762-2017规定的限量(0.05mg·kg^(-1)),且该方法测定结果和GB 5009.268-2016中的微波消解-电感耦合等离子体质谱法(ICP-MS)测定结果无显著性差异。
Content of lead in the milk sample solution after diluted with 0.20 g·L^(-1)Triton X-100 diluted solution(containing 0.20% nitric acid),was determined by graphite furnace-atomic absorption spectrometry under the optimized instrument working conditions.0.20 g·L^(-1)palladium nitrate solution as matrix modifier was added online,thus to remove matrix interference.A standard curve was made by using matrix matching standard solution series,and results obtained showed that linearity relationships between mass concentration of lead and the corresponding absorbance were kept in the ranges of 1.00-4.00μg·L^(-1)and 6.00-24.0μg·L-1,with detection limit(3 s)of 1.90μg·kg^(-1).Recovery test to milk samples was made at 4 concentration levels,giving recoveries in the range of 97.2%-102%,and RSDs of the determined values(n=5)were ranged from 1.5%to 13%,meeting the requirements of appendix F in national standard GB/T 27404-2008.The proposed method was used in analyzing of 8 milk samples,with mass fraction of lead all less than the limit(0.05 mg·kg^(-1))specified in the national standard GB 2762-2017,and the results of determination obtained had no significant difference with those of ICP-MS after microwave digestion given in GB 5009.268-2016.
作者
戴瑞平
刘花梅
陈林
DAI Ruiping;LIU Huamei;CHEN Lin(Jiangxi Instituse for Food Control,Nanchang 330001,China)
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2021年第1期57-61,共5页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
