Magnesium/aluminum-layered double hydroxide modified with hydrogen peroxide as a novel fiber coating for solid-phase microextraction of phthalate esters in aqueous samples

摘要

A novel coating material for solid-phase microextraction (SPME) was synthesized by treating magnesium/aluminum-layered double hydroxide (Mg/Al-LDH) with hydrogen peroxide in the presence of potassium iodide and was confirmed to be chemically and thermally stable. A direct immersion solid-phase microextraction method to determine phthalate esters (PAEs) in aqueous samples was developed using the constructed fiber coating to couple with gas chromatography. Several factors on SPME procedure were investigated in detail. Under the optimized conditions, the linear ranges of the developed method were between 1 and 500 mu g L-1. The limits of detection and the limits of quantification for various phthalates were in the range of 0.42-1.29 mu g L-1 and 1.40-4.13 mu g L-1, respectively. The run-to-run RSD (n = 5) and the fiber-to-fiber RSD (n = 3) were 8.30-20.0% and 8.50-20.4%, respectively. This method was successfully applied to the analysis of PAEs from Yangtze River water samples and bottled mineral samples.