Simultaneous Determination of 14 Inorganic Elements in Plant-Original New Food Sources by ICP-MS

The sample (0.500 0 g) was digested with 3 mL of nitic acid and 2 mL of hydrogen peroxide, and Na, Mg, Ca, Al, Cu, Zn, Fe, Mn, Se, Pb, Cd, As, Hg, Cr in the sample solution were determined by ICP-MS. Acidity of φ 0.5% HNO₃ of the sample solution was adopted to enhance signal intensities of the 14 elements. The instrument was washed with 100 μg·L^-1 Au in φ 5% HNO₃ solution between 2 determinations to lower the adsorption effect of Hg. Mass spectral interference was eliminated using DRC mode with CH₄ as reaction gas. Sc, Y, In and Bi were selected as the internal standards to correct matrix effect. Linear relationships were found between signal intensities and mass concentrations of the 14 elements in definite ranges, with detection limits (3s) in the range of 0.003-0.039 μg·L^-1. The method was used to analyze a CRM numbered GBW 10027, giving determination values of 14 elements in consistency with the certified values and RSDs (n=6) in the range of 1.6%-14%.