DEVELOPMENT AND ANALYTICAL EVALUATION OF A PAR-IMMOBILIZED SORBENT FOR THE SORPTION-SPECTROPHOTOMETRIC DETERMINATION OF Pb(II) IONS

The determination of Pb(II) ions at trace levels is of great importance due to their toxicity, persistence, and adverse effects on human health and aquatic ecosystems. In this study, a sorption-spectrophotometric method based on a 4-(2-pyridylazo)resorcinol (PAR)-immobilized sorbent was developed and analytically evaluated for the determination of Pb(II) ions in aqueous solutions. The sorbent was prepared by immobilizing PAR onto a silica gel matrix to obtain a stable and selective adsorption surface. The effects of solution pH, contact time, sorbent dosage, and initial Pb(II) concentration were systematically optimized to establish the optimum analytical conditions. Under the optimized conditions, the proposed sorbent exhibited high adsorption efficiency, excellent sensitivity, and good selectivity toward Pb(II) ions. The developed method demonstrated satisfactory linearity, precision, accuracy, and reproducibility, making it suitable for the determination of trace Pb(II) ions in environmental water samples. The results indicate that the PAR-immobilized sorbent provides a simple, rapid, cost-effective, and environmentally friendly approach for the sorption-spectrophotometric determination of Pb(II) ions.