Determination of Sb(V) in water samples via solid-phase extraction based on Mg–Al layered double hydroxide sorbents prior to ICP-MS

Solid-phase extraction (SPE) is an effective method for detecting trace metals. Mg-Al-layered double hydroxide (Mg-Al LDH) materials as an effective adsorbent for SPE because of its large anion exchange capacity, high yield and low cost. A new method was developed for detecting Sb(V) with SPE coupled with inductively coupled plasma mass spectrometry. Mg-Al LDH was synthesized via a simple coprecipitation method and characterized using scanning electron microscopy, Fourier transform infrared spectrometry, X-ray diffractometry, and X-ray photoelectron spectroscopy. Factors affecting the Sb(V) extraction efficiency, such as the eluent type and volume, solution pH, loading flow rate, sample volume, adsorbent weight, and salt concentration, were optimized. Under optimal conditions, the SPE method exhibited good linearity (R² ≥ 0.999) in the range of 0.1–100 μg L⁻¹ with a limit of detection equal to 0.017 μg L⁻¹, good repeatability and reproducibility, and intraday and interday relative standard deviations of 1.84% and 1.48%, respectively. Furthermore, the method was applied to determine traces of antimony in drinking water and bottled water, and findings revealed recoveries between 82.7%–92.1%.