Simultaneous speciation of inorganic selenium and tellurium in environmental water samples by polyaniline functionalized magnetic solid phase extraction coupled with ICP-MS detection

Herein, polyaniline functionalized magnetic nanoparticles (MNPs) were prepared and investigated as the adsorbents for the separation and enrichment of inorganic selenium and tellurium species. The prepared Fe₃O₄@SiO₂@polyaniline (PANI) MNPs presents selective adsorption performance for Se^IV and Te^IV, along with fast adsorption and desorption dynamics. Based on it, a method combining magnetic solid phase extraction (MSPE) with inductively coupled plasma mass spectrometry (ICP-MS) was developed for the simultaneous speciation of inorganic Se and Te in environmental waters. The adsorption mechanism was investigated preliminarily. Various parameters affecting Fe₃O₄@SiO₂@PANI MSPE of Se^IV and Te^IV were investigated. Under the optimized conditions, the limits of detection (3σ) for Se^IV and Te^IV were found to be 5.3 and 1.2 pg mL^-1, with the relative standard deviations (c_Se(IV) = 100 pg mL^-1, c_Te(IV) = 10 pg mL^-1, n = 7) of 3.8 and 8.0%, respectively. The enrichment factor of the proposed method is 100-fold. The proposed method was successfully applied to the speciation of inorganic Se and Te in environmental water samples. The developed MSPE-ICP-MS method possesses the advantages of low cost, high enrichment factor, rapid operation and can simultaneously analyze inorganic Se and Te species in real-world samples.