Magnetic Adsorbent Decorated with Poly(N-Isopropylacrylamide) (PNIPAM) Brushes for the Vortex-Assisted Solid Phase Extraction (VASPE) of Lead in Water, Cigarettes and Soil with High-Resolution Continuum Source Flame Atomic Absorption Spectrometry (HR-CS FAAS) Detection

Abstract

Here is reported the synthesis of a magnetic phosphorus-containing adsorbent decorated with poly(N-isopropylacrylamide) (PNIPAM) brushes via surface-initiated atom transfer radical polymerization (SI-ATRP) and its application for vortex assisted solid phase extraction of lead in water, cigarettes and soil. The adsorbent was characterized using Fourier-transform infrared spectroscopy (FT-IR) and energy dispersive x-ray (EDX) spectroscopy. A high-resolution continuum source flame atomic absorption spectrometer (HR-CS FAAS) was used for the quantification of lead. All factors affecting the extraction efficiency including the solution pH, adsorbent dose, sample volume, vortex time, and elution protocols were optimized. The limits of detection (LOD) and quantification (LOQ) were determined to be 0.05 µg L−1 and 0.18 µg L−1, respectively. The preconcentration and enhancement factors were 20 and 18. Validation was performed using TMDA 64.3 fortified water and INCT-OBTL-5 tobacco leaves certified reference materials with satisfactory recoveries. The method was shown to be sensitive, efficient and reproducible.