Determination of Pb(II) Ion with a Novel, Highly Efficient Immobilized Arsenazo III in a Polymer Matrix

In this study, a novel analytical reagent based on arsenazo III immobilized on a polymer matrix composed of polyacrylonitrile, polyethylene polyamine, and dichloroethane (PPD) was developed and applied for the spectrophotometric determination of Pb(II) ions. The proposed method demonstrated standard analytical and metrological characteristics for the highly accurate determination of Pb(II) ions, as evidenced by a relative standard deviation (Sr) of 0.06 and a minimum detectable concentration (Cmin) of 0.24 μ g/L. The accuracy and reproducibility of the method were evaluated using Student's t-test and Fisher's F-test. Comparison of the experimental and tabulated values (experiment=1.09; ttable=2.83, Fexperiment=2.52; Ftable=4.47) confirmed the reliability of the proposed analytical procedure. At pH 5.8 in an acetate buffer medium, the Pb(II)–arsenazo III complex immobilized on the PPD matrix exhibited a maximum analytical signal at a wavelength of 640 nm. The measurement results followed the Beer–Lambert–Bouguer law, showing a linear relationship in the Pb(II) concentration range of 0.04–2.4 μ g/mL. The method is simple, rapid, cost-effective, and allows direct Pb(II) ion determination in water samples with high sensitivity and selectivity.