Determination of 30 Trace Elements in Rice Based on ICP-MS/MS

In 5 kinds of rice samples, the method for determining 30 common trace elements in rice was established. The rice sample was digested by microwave and then injected for analysis by inductively coupled plasma tandem mass spectrometry(ICP-MS/MS) technology. In MS/MS mode, H₂, O₂, and NH₃ were used as the reagent gas to cause the interference or analytes to undergo a mass transfer reaction with the reagent gas, using in-situ mass method or mass transfer method to eliminate mass spectrum interference. The results showed that the linear relationship of the test elements was good, and the linear correlation coefficient was more than 0.9991. The limits of detection were in the range of 0.000251～2.322 mg/kg. Recoveries of the method were in range of 95.50%～104.35%, and the relative standard deviations RSD was less than 4.03%. The established method was used to determine the rice from different regions in China. The results showed that the content of P, S, K, and Mg in the five kinds of rice was higher,between 53.7~736 mg/kg, while the content of heavy metal elements Cr, As, Cd, and Pb was very low. This method has the characteristics of simple sample preparation, high sensitivity and low detection limit, and can accurately monitor the trace elements in rice.