Online simultaneous speciation of ultra-trace inorganic antimony and tellurium in environmental water by polymer monolithic capillary microextraction combined with inductively coupled plasma mass spectrometry

Abstract

Poly(glycidyl methacrylate-ethylene dimethacrylate) monolithic capillary was functionalized with cystamine, and the resultant mercapto functionalized polymer monolithic capillary was investigated for the separation of Sb(III) and Sb(V) as well as Te (IV) and Te(VI). It was found that Sb(III) and Te(IV) were selectively retained on the prepared monolithic capillary over a wide pH range (1–8), while Sb(V) and Te(VI) were not be adsorbed in the pH range of 3–8. Based on it, a method of capillary microextraction online hyphenated with ICP-MS was proposed for simultaneous speciation of trace inorganic Sb and Te. Sb(V) and Te(VI) were pre-reduced simultaneously into Sb(III) and Te(IV) and subjected to the proposed method to get the information of total Sb and Te; the content of Sb(V) and Te(VI) was calculated by subtracting Sb(III) and Te(IV) from total Sb and Te. Under the optimized conditions, the limits of detection for Sb(III) and Te(IV) were 3.9 and 5.9 ng L−1 with the relative standard deviations of 5.2 and 4.1% (c = 0.1 μg L−1, n = 7), respectively. The accuracy of the method was verified by Certified Reference Materials of Environmental Water (GSB07–1376-2001, GBW(E)080548). In real water samples analysis, sub-μg L−1 of Sb(V)/(III) was found in the Yangtze River and East Lake water, and the recoveries for the spiked real water samples for Sb(V)/(III) and Te(IV)/(VI) were 87.0–113% and 83.5–107%, respectively. The proposed approach was rapid, sensitive and exhibited great application potential in the simultaneous speciation of inorganic Sb and Te in environmental waters.