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Updated: Feb 12, 2026
Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites
Published on: September 19, 2020
A nanocomposite consisting of MIL-101(Cr) and functionalized magnetite nanoparticles for extraction and determination
Hossein Kalantari1, Mahboobeh Manoochehri2
1Department of Chemistry, Central Tehran Branch, Islamic Azad University, Tehran, 1467686831, Iran.
Abstract:
A metal-organic framework nanocomposite was synthesized and applied to speciation analysis of Se(IV) and Se(VI). The sorbent is composed of MIL-101(Cr) and magnetite nanoparticles modified with dithiocarbamate. It is capably of selectively extracting Se(IV) at pH = 1.85, while Se(VI) remains in solution. The total amount of selenium can then be determined by reducing Se(VI) to Se(IV) and also extracting it. The extraction parameters were optimized by employing design-of-experiments methodology. Selenium was then quantified by electrothermal AAS. Figures of merit include (a) a 10 ng·L-1 limit of detection, (b) a linear response in the 30 ng·L-1 to 10 μg·L-1 concentration range, and (a) a relative standard deviation of <11.5% for Se(IV). The method was validated by analyzing certified reference materials (water and tomato leaves). It was also applied to the speciation analysis of Se(IV) and Se(VI) in (spiked) water samples and of total selenium in agricultural samples. Graphical abstract Schematic of the synthesis of a metal-organic framework nanocomposite for speciation analysis of Se(IV) and Se(VI). The sorbent is composed of MIL-101(Cr) and magnetite nanoparticles modified with dithiocarbamate. Selenium can be quantified by electrothermal AAS with a 10 ng L-1 detection limit.
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