A dual-purpose β-cyclodextrin-derived sorbent decorated with chelating residues of aminomethylphosphonate and aspartic acid for removal of polyaromatic hydrocarbons and toxic metal ions

The occurrence of polyaromatic hydrocarbons (PAHs) and heavy metals (HMs) in aqueous bodies posed a serious environmental threat to humans and wildlife. A cross-linked resin (CLR) having β-CD (for PAHs extraction) and aspartic acid and methylenephosphonate motifs (as scavenger for Pb(II) and Hg(II)) has been synthesized. The CLR was used in a stir bar-supported micro-solid-phase extraction (SB-µ-SPE) technique for extraction of PAHs from aqueous samples and analyzed by gas chromatography – mass spectrometry (GC–MS). Optimization of the method was carried out using a wide number of parameters. Optimum extraction performance was achieved using 5 mg of the CLR, under PAHs extraction and desorption time of 2.5 min and 10 min respectively. 400 µL of dichloromethane gave the best desorption experience, and the optimum ionic strength was maintained using 2 g NaCl. The HMs removal study was conducted in ppm to ppb level concentration (1 ppm–200 ppb). The CLR extracts the PAHs and adsorbs the HMs with excellent efficiency. The developed extraction method delivered good linearity range for all the PAHs with R² value in the range 0.9319–0.9939 and detection limit range 0.028–0.33 ng mL⁻¹. The synthesized CLR may thus be used for the removal of the PAHs and HMs from contaminated water sources.