Quinoline‐Based Polymers for Selective and Efficient Adsorption/Solid‐Phase Extraction of Pb(II) and Zn(II) from Water

Abstract In this study, two quinolone‐based polymers were used for the adsorption and solid‐phase extraction (SPE) of Pb(II) and Zn(II) from water. The polymers were synthesized via a Suzuki coupling reaction, and their structures were confirmed by IR and NMR analyses. Batch adsorption experiments at varying pH showed that both polymers removed approximately 50% of Pb(II) and 40% of Zn(II), with negligible uptake of Cd(II), Co(II), and Mn(II) (<10%), indicating good selectivity. Poly─Q─OBz exhibited superior adsorption capacity based on isotherm analysis. SPE conditions were optimized at pH 8, with a flow rate of 1.7 mL min⁻¹ and elution using 0.5 M HNO₃, achieving recoveries of Pb(II) and Zn(II) greater than 90%, even in the presence of competing ions. Spiked concentrations (0.2–10 mg L⁻¹) yielded the following performance metrics: LODs of 0.0064 and 0.0011 mg L⁻¹, dynamic ranges of 0.0213–10.0 and 0.0036–10.0 mg L⁻¹, sensitivities of 0.258 and 1.546 L mg⁻¹, and enrichment factors of 9.0 and 9.2. This method was successfully applied to real water samples, demonstrating that the polymers are efficient, selective, reusable, and cost‐effective.