Determination of Trace Selenium in Tobacco by Triple Quadrupole ICP-MS

In order to determine trace element selenium in tobacco leaves accurately, a triple quadrupole ICP-MS method was used to determine trace selenium in tobacco leaves, and the results were compared with that from single quadrupole ICP-MS. The results showed that when triple quadrupole ICP-MS was used for mass screening by bipolar mass spectrometry, O₂ was chosen as reaction gas to transfer the mass number of Se to the undisturbed region, the interference of polyatomic ions and double charged ions can be eliminated and more accurate results can be obtained. The recovery rates of the isotopes ⁷⁸Se, ⁸⁰Se and ⁸²Se were 99.1%, 98.3%, 99.2% respectively. The relative deviation (RSD) was 1.59%, 2.07%, and 1.32% respectively. The linear correlation coefficient was r>0.9999. It was indicated that the interference factor was small and the results were more accurate for the determination of trace selenium in tobacco by triple quadrupole ICP-MS.