A novel poly(2-mercaptobenzothiazole) coated magnetic nanoadsorbent derived from ZIF-8 for preconcentration/determination of palladium and silver.

Herein, a novel poly(2-mercaptobenzothiazole) coated magnetic nanoadsorbent derived from zeolitic-imidazole framework-8 (ZIF-8) was synthesized and then employed for the extraction/preconcentration of trace amounts of palladium and silver in various real matrixes. In this way, magnetite was fabricated first, and then functionalized with tetraethyl orthosilicate. After that, the synthesized magnetite@silica was coated with the ZIF-8 to obtain magnetic ZIF-8.

Fabrication of a novel magnetic metal-organic framework functionalized with 2-aminothiophenol for preconcentration of trace silver amounts in water and wastewater.

Herein, a novel magnetic metal-organic framework functionalized (MMOF) with 2-aminothiophenol (2-ATP) was fabricated and employed for separation/preconcentration of trace silver amounts. At first magnetite nanoparticles (FeO NPs) were synthesized and then coated with SiO. Thereafter, the FeO@SiO nanoparticles were modified with 2-ATP.

Selective extraction and determination of beryllium in real samples using amino-5,8-dihydroxy-1,4-naphthoquinone functionalized magnetic MIL-53 as a novel nanoadsorbent.

Herein, a magnetic MOF for preconcentration of Be(ii) was synthesized. The material is obtained from magnetite (FeO) nanoparticles that were modified with 2-amino-5,8-dihydroxy-1,4-naphthoquinone (ADHNQ) and then reacted with terephthalic acid and iron(iii) chloride to form a metal-organic framework of the type MIL-53(Fe) capable of extracting Be(ii). The extraction parameters were optimized by employing design of experiments methodology.

Synthesis of multi-functionalized FeO-NH-SH nanofiber based on chitosan for single and simultaneous adsorption of Pb(II) and Ni(II) from aqueous system.

A multi-functionalized poly ether sulfone (PES)/ chitosan (CS)/FeO-NH-SH nanofiber was applied for single and simultaneous removal of Pb(II) and Ni(II) ions from water systems. The structure of nanofibers was evaluated using FTIR, FESEM, BET, BJH, TGA, EDX and XPS analyses. The characterization results showed that the structure of nanofibers was well maintained after adsorption process.

Liquid chromatographic determination of trace levels of nitrophenols in water samples after dispersive magnetic solid phase extraction.

An efficient and fast dispersive magnetic solid phase extraction method was developed using MIL-101(Cr)/poly (mercaptobenzothiazole)@magnetite nanoparticles for the preconcentration and determination of nitrophenols in river and rain water samples. High-performance liquid chromatography-Ultraviolet instrument was applied for the analysis of target nitrophenols. The effect of several variables on the extraction performance was explored via design of experiment approach.

Speciation analysis of Tl(I) and Tl(III) after magnetic solid phase extraction using a magnetite nanoparticle composite modified with aminodibenzo-18-crown-6 functionalized MIL-101(Cr).

The authors describe a magnetic metal-organic framework nanocomposite consisting of aminodibenzo-18-crown-6 magnetite nanoparticles and MIL-101(Cr). It was employed to the speciation analysis of Tl(I) and Tl(III) ions. The sorbent is capable of selectively extracting Tl(I) while Tl(III) remains in solution.

A nanocomposite consisting of MIL-101(Cr) and functionalized magnetite nanoparticles for extraction and determination of selenium(IV) and selenium(VI).

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.

Synthesis, characterisation and analytical application of Fe₃O₄@SiO₂@polyaminoquinoline magnetic nanocomposite for the extraction and pre-concentration of Cd(II) and Pb(II) in food samples.

This work describes a novel Fe₃O₄@SiO₂@polyaminoquinoline magnetic nanocomposite and its application in the pre-concentration of Cd(II) and Pb(II) ions. The parameters affecting the pre-concentration procedure were optimised by a Box-Behnken design through response surface methodology. Three variables (extraction time, magnetic sorbent amount and pH) were selected as the main factors affecting the sorption step, while four variables (type, volume and concentration of the eluent, and elution time) were selected as main factors in the optimisation study of the elution step.

Determination of Aflatoxin M1 in Milk Powder by Ultrasonic-Assisted Extraction and Dispersive Solid-Phase Clean-up.

This work describes the application of ultrasound-assisted dispersive solid-phase extraction (UA-DSPE) as a sample preparation approach for aflatoxin M1 (AFM1) and also its subsequent determination by HPLC-fluorescence detection. A Box-Behnken design in combination with response surface methodology was implemented to determine the variables affecting the extraction procedure. The effects of different variables, including type and quantity of clean-up phase, ultrasonication time, ultrasonication temperature, nature and volume of the leaching solvent, were investigated in the optimization study.

Determination of aflatoxins in rice samples by ultrasound-assisted matrix solid-phase dispersion.

This work describes the application of ultrasound-assisted matrix solid-phase dispersion as an extraction and sample preparation approach for aflatoxins (B1, B2, G1 and G2) and subsequent determination of them by high-performance liquid chromatography-fluorescence detection. A Box-Behnken design in combination with response surface methodology was used to determine the affecting parameters on the extraction procedure. The influence of different variables including type of dispersing phase, sample-to-dispersing phase ratio, type and quantity of clean-up phase, ultrasonication time, ultrasonication temperature, nature and volume of the elution solvent was investigated in the optimization study.

Multivariate optimisation of an ultrasound assisted-matrix solid-phase dispersion method combined with LC-fluorescence detection for simultaneous extraction and determination of aflatoxins in pistachio nut samples.

This paper describes the application of ultrasound-assisted matrix solid-phase dispersion as an extraction and clean-up procedure for aflatoxins (B1, B2, G1 and G2) and subsequent determination by LC-fluorescence detection. A Box-Behnken design was used to determine the parameters influencing the extraction procedure through response surface methodology and experimental design. The influence of different variables including type of dispersing phase, sample-to-dispersing phase ratio, type and quantity of clean-up phase, ultrasonication time, ultrasonication temperature, nature and volume of the elution solvent were investigated in the optimisation study.