超级微波消解-电感耦合等离子体质谱(ICP-MS)法测定小麦中13种元素

Determination of 13 elements in wheat by inductively coupled plasma mass spectrometry with ultra microwave digestion

目前对于小麦籽粒的消解大多数采用微波和湿法等常规方法,关于超级微波消解小麦籽粒的研究尚未报道。为了寻求一种更高效测定小麦中Mg、P、K、Ca、Mn、Fe、Ni、Cu、Zn、Sr、Mo、Ba和Pb共13种元素含量的方法,选择超级微波进行小麦籽粒样品消解,优化了消解体系的酸度,并将其与湿法消解、微波消解两种方法进行比较,发现超级微波消解法加酸量较少,消解时间更短且操作较为简便。结果表明,超级微波消解-ICP-MS法标准曲线线性关系良好,相关系数(R2)均大于0.999 8,线性范围宽,方法检出限范围为0.001 80~3.11 mg/kg,加标回收率范围为80.94%~109.95%,精密度在2.37%~4.95%。可靠性试验结果表明,超级微波消解-ICP-MS法测定值与标准参考值偏差小于7.71%,研究为小麦籽粒样品元素分析工作提供了一种安全、高效、准确的支撑方法。

Currently most conventional methods such as microwave digestion and wet digestion are used on wheat grain, and studies of ultra microwave digestion of wheat grain has not yet been reported. To discover a more rapid method for measuring the content of 13 elements in wheat, i.e. Mg, P, K, Ca, Mn, Fe, Ni, Cu, Zn, Sr, Mo, Ba and Pb, ultra microwave digestion is selected to digest wheat grain samples and to compare with two conventional digestion methods, namely wet digestion and microwave digestion, meanwhile the acid degrees of digestion system is optimized. It is found that the ultra microwave digestion method requires a smaller amount of acid, consumes less time and is easier to operate. The results show that the standard curve of the ultra microwave digestion-inductively coupled plasma mass spectrometry(ICP-MS) method is characterized by an ideal linear relationship, with a correlation coefficient(R2) of greater than 0.999 8, a wide linear range, a detection limit ranging from 0.001 80 mg/kg to 3.11 mg/kg, an adding standard recovery rate of 80.94%~109.95%, and a precision that varies from 2.37% to 4.95%. Based on the results obtained in the reliability test, there is a deviation of less than 7.71%between the value measured by the ultra microwave digestion-ICP-MS method and the standard reference value.This paper provides a safe, efficient and accurate method to support the elemental analysis of wheat grain samples.