Nickel Ferrite Magnetic Nanoparticles as a Sorbent for Solid Phase Extraction of Trace Lead from Water Prior to Spectrophotometric Determination

Resumo

In this study, nickel ferrite magnetic nanoparticles adsorbent was synthesized and developed for solid phase extraction and spectrophotometric determination of trace amounts of lead ions in aqueous media. The adsorbent was characterized by X-ray diffraction, transmission electron microscopy and vibrating sample magnetometry. The magnetic separated lead ions were eluted and quantified based on the complex formation of lead ions with 1,5-diphenylthiocarbazone at pH 8.5. The influence of variables affecting the efficiency of the extraction system, such as sample pH, amount of adsorbent, type and volume of desorption solvent and contact time, was evaluated and optimized. Under the optimal conditions, a linear calibration curve in the range from 0.004 to 0.6 μg/mL was obtained with a preconcentration factor of 80. The limit of detection for lead was found to be 0.27 ng/mL. The developed method was successfully applied for the determination of trace amounts of lead ions in various water samples with satisfactory results.