Trace amount determination of Cd(ii), Pb(ii) and Ni(ii) ions in agricultural and seafood samples after magnetic solid phase extraction by MIL-101(Cr)/phenylthiosemicarbazide-functionalized magnetite nanoparticle composite

Abstract

Herein, a novel magnetic metal–organic framework nanocomposite consisting of phenylthiosemicarbazide magnetite nanoparticles (Fe₃O₄@PTSC) and MIL-101(Cr) was synthesized, characterized and utilized in the magnetic solid phase extraction of heavy metals including Cd(II), Pb(II) and Ni(II) ions in various agricultural and seafood samples. After extraction, flame atomic absorption spectrometry was employed to determine the target analytes. The effects of various parameters on the method performance were explored thoroughly via experimental design. By employing optimum conditions, detection limits, quantification limits, linear dynamic ranges and extraction recoveries were obtained in the ranges of 0.07–0.5 μg kg⁻¹, 0.2–2.0 μg kg⁻¹, 0.25–250 μg kg⁻¹ and 97.5–99.0%, respectively. The relative standard deviations (n = 5) were between 4.5% and 7.3%. The method was validated using a certified reference material (DOLT-4). Eventually, this new method was applied for the determination and extraction of target analytes in different agricultural and seafood samples.