电感耦合等离子体质谱法测定云南市售大米中4种有益元素

目的建立石墨湿法消解-电感耦合等离子体质谱法同时测定云南大米中4种有益元素含量的方法。方法以产自云南省12个州市共90件大米为实验对象,采用石墨湿法消解对样品进行前处理,电感耦合等离子体质谱法进行测定,内标法定量分析云南大米中锰(Mn)、铁(Fe)、铜(Cu)、锌(Zn)4种有益元素的含量。结果云南大米中锰、铁、铜、锌4种金属元素在0~100μg/L质量浓度范围内呈现良好的线性关系,相关系数均大于0.999。通过加标回收实验分析锰、铁、铜、锌4种金属元素的加标回收率依次为93.61%~100.37%、88.32%~105.47%、99.91%~101.78%、94.14%~102.89%,相对标准偏差依次为3.37%、1.02%、0.16%、1.18%,4种金属检出率均为100%。结论石墨湿法消解-电感耦合等离子体质谱法精密度好、准确度高,可同时测定大米中多种金属,适用于云南大米中锰、铁、铜、锌含量的测定。

Determination of 4 beneficial elements in Yunnan commercial rice by inductively coupled plasma mass spectrometry

Objective To determine the content of beneficial metals in yunnan rice by inductively coupled plasma mass spectrometry (icp-ms) and graphite digestion. Methods A total of 90 pieces of rice from 12 cities in yunnan province were taken as the experimental object. The samples were pretreated by graphite digestion method and determined by inductively coupled plasma mass spectrometry (icp-ms). The contents of four beneficial elements in yunnan rice were quantitatively analyzed by internal standard method. Results The results showed that there was a good linear relationship between the concentrations of manganese, iron, copper and zinc in yunnan rice in the range of 0 ~ 100 g/L, and the correlation coefficients were all greater than 0.999. The standard recovery rates of manganese, iron, copper and zinc were 93.61~100.37% and 88.32 ~105.47%, 99.91~101.78%, 94.14~102.89%. The relative standard deviation was 0.13%, 0.11%, 0.10% and 0.09%, respectively, when the standard solution of manganese, iron, copper and zinc was measured for 6 times in parallel. In 90 yunnan rice samples, manganese, iron, copper and zinc were all detected, and the detection rate was 100%. Conclusion The method of graphite digestion and inductively coupled plasma mass spectrometry is suitable for the determination of manganese, iron, copper and zinc in yunnan rice. There were differences in the content of the four beneficial metals in yunnan rice.