Abstract:An analytical method to detect selenium species such as selenate [Se(IV)], selenite [Se(VI)], selenomethionine (SeMet), selenocystine (SeCys2), and selenoethionine (SeEt) in genetically modified soybean was established using high-performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The effects of the chromatographic column, mobile phase, and acidity on separation were evaluated. Hamilton PRP X-100 reversed phase anion exchange column with 10 mmol/L citric acid solution as the mobile phase was used for separation. Collision cell technology was adopted to eliminate the interference of polyatomic ions such as 40Ar40Ar+ and 40Ar2H2+. Isotope 82Se was detected by ICP-MS. The five species were completely separated within 21 min. The extraction procedure was discussed and optimized. A spiked recovery experiment was carried out with proteinase extration, using genetically modified soybean imported from the USA. The result showed that the recoveries were around 100% for Se(IV) and Se(VI), was in the range 92.6%–109.3% for SeMet, and they were in the range 81.2%–95.9% for SeCys2 and SeEt. This method can be used for the quantitative determination of selenium species in genetically modified soybeans.
