Magnetic Framework Composites Research Articles

Preparation of magnetic framework composites Fe3O4@MIL-100(Fe) and adsorption of lead in water

Preparation of magnetic framework composites Fe3O4@MIL-100(Fe) and adsorption of lead in water

Continuous flow synthesis of MOF UTSA-16(Zn), mixed-metal and magnetic composites for CO2 capture – toward scalable manufacture

UTSA-16(Zn) is a zinc and citrate-based metal-organic framework (MOF) which has shown highly promising performance for CO2 capture. However, the transition of this MOF to industrial application has been hindered as a scalable synthesis method has not yet been reported. Herein we report the first scalable continuous flow synthesis of UTSA-16(Zn), demonstrating a production rate of 173 g/h, which is a 77-fold increase compared to previously reported batch methods. Sustainability of the synthesis was maximised using low-cost non-toxic reagents and a low-energy flow reactor operating at atmospheric pressure. Chemical (reactant ratios, Zn/Mg mixed-metal) and process parameters (solvent ratio, flow rate, temperature) were optimised to continuously produce UTSA-16(Zn) which also demonstrated a high CO2 adsorption capacity up to 3.8 mmol/g and conversion yield of up to 66 %. Pristine MOFs are typically thermally insulating, thus thermal regeneration is challenging. To overcome this limitation, magnetic nanoparticles can be embedded within the MOF. This enables fast and energy efficient regeneration through magnetic induction heating. Here, citrate-coated Fe3O4 magnetic nanoparticles (MNP-CA) were successfully incorporated into the flow synthesis process of UTSA-16(Zn) to form UTSA-16(Zn)@MNP-CA magnetic framework composites (MFCs), representing the highest production rate reported of any MFC to date (152 g/h c.f. 13 g/h for MgFe2O4@UiO-66-NH2). UTSA-16(Zn)@MNP-CA MFCs demonstrate rapid heating under a magnetic field (26–150 °C in 60 s). The flow method developed herein is also widely applicable for scalable manufacture of other MOFs and MFCs, enabling their broader transition towards industrial applications.

Synthesis and application of magnetic graphene oxide covalent organic framework composite for extraction of anabolic androgenic steroids and β-agonists in animal urine and tissue samples

In this work, a magnetic graphene oxide covalent organic framework composite was synthesized and utilized as an effective sorbent for magnetic solid phase extraction. A comprehensive investigation was conducted to optimize the extraction conditions, including sample pH, sample volume, adsorbent amount, adsorption time, choice of elution solution, elution volume, elution time, and ionic strength. Subsequently, the developed extraction method was combined with liquid chromatography-tandem mass spectrometry for the detection of 7 anabolic androgenic steroids and 4 β-agonists. Under the optimized condition, the limits of detection for the 7 anabolic androgenic steroids and 4 β-agonists ranged from 0.5 to 2 ng L−1, with relative standard deviations varying from 4.18 % to 12.4 % at a concentration of 0.025 μg L−1. Calibration curves were established using the peak area of analytes at concentrations spanning 5–500 ng L−1, resulting in correlation coefficients within the range of 0.9949–0.9989. The enrichment factors achieved through magnetic solid phase extraction were found to be 91.4–97.3. The proposed method was successfully applied for the determination of target analytes in hog urine, bovine urine, beef, mutton, pig liver and pork powder samples. Ractopamine and clenbuterol were identified in the pork powder (quality control sample) at concentrations of 21.0 μg kg−1 and 42.6 μg kg−1, respectively. The proposed method is a sensitive, reliable, and convenient analytical method for anabolic androgenic steroids and β-agonists monitoring in animal urine and tissues.

Construction of magnetic COF composites for lead removal with fast dynamics and superior capacity

BackgroundThe removal of heavy metals is very important because of their nonbiodegradability and toxicity to the general population and environment. Adsorption is regarded as a promising approach for target pollutant removal due to its simplicity and economy. MethodsNovel magnetic covalent organic framework (COF) composites (Fe3O4@TpPa-NO2) consisting of a magnetic Fe3O4 core and a TpPa-NO2 COF shell are synthesized and developed as adsorbents for Pb(II) removal from aqueous solution. Significant findingsThe obtained composites exhibit superior adsorption performance (909.1 mg/g) and fast adsorption dynamics (adsorption equilibration time of less than 10 min) toward Pb(II). The experimental data for the adsorption of Pb(II) follow pseudo-second-order kinetic and Langmuir isotherm models. The superior performance of Fe3O4@TpPa-NO2 for Pb(II) elimination is attributed to electrostatic and coordination interactions between the metal ion and functional groups (nitrogen and oxygen) of magnetic COF composites. The Pb(II)-loaded Fe3O4@TpPa-NO2 can be easily regenerated by acid treatment. Furthermore, Fe3O4@TpPa-NO2 demonstrates excellent reusability and maintains a high removal efficiency throughout five consecutive adsorption-desorption processes. Various COF-based magnetic adsorbents can be fabricated for specific pollutants due to the diversity in the structure and pore size of the COFs, which present attractive prospects for high-efficiency removal of contaminants in water treatment.

One-pot encapsulation of lactate dehydrogenase and Fe3O4 nanoparticles into a metal-organic framework: A novel magnetic recyclable biocatalyst for the synthesis of D-phenyllactic acid.

The main challenges in bio-catalysis of d-phenyllactic acid (D-PLA) are poor tolerance of lactate dehydrogenase (LDH) to harsh environmental conditions and inability to recycle the catalyst. A novel magnetic framework composite was prepared as solid support for the immobilization of enzymes via one-pot encapsulation in this study. LDH/MNPs@MAF-7 was synthesized by the one-pot encapsulation of both LDH and magnetic nanoparticles (MNPs) in MAF-7. The LDH/MNPs@MAF-7 showed stable biological activity for the efficient biosynthesis of D-PLA. The structure and morphology of LDH/MNPs@MAF-7 were systematically characterized by SEM, FT-IR, XRD, VSM, XPS, TGA and N2 sorption. These indicated that LDH/MNPs@MAF-7 was successfully synthesized, exhibiting enhanced resistance to acid and alkali, temperature and organic solvents. Furthermore, the bio-catalyst could be separated easily using a magnet, and the reusability was once considerably expanded with 80% of enzyme activity last after eight rounds of recycling. Therefore, LDH/MNPs@MAF-7 could be used as a potential biocatalyst for the biosynthesis of D-PLA due to its good stability and recovery properties.

Development of core@shell magnetic framework composite for immunoselective detection and capture of Salmonella typhimurium

A Fe3O4/Si@MIL-125 magnetic framework composite is demonstrated for optical detection and simultaneous removal of pathogenic Salmonella typhimurium. The fabricated nanomaterial exhibited promising opto-magnetic properties and stability.

Rapid synthesis of magnetic microspheres and the development of new macro–micro hierarchically porous magnetic framework composites

Highly porous magnetic microspheres are synthesised through a flame spheroidisation process and surface functionalised. Metal–organic frameworks are then grown on the surfaces to produce novel hierarchically porous magnetic framework composites.

A Novel "Turn on" Chemiluminescence Aptasensor for Alpha Fetoprotein Detection Based on Oligonucleotide Chain Functionalized Magnetic Graphene Oxide and Co-Catalyzed Copper-Based Organic Framework Composites

A Novel "Turn on" Chemiluminescence Aptasensor for Alpha Fetoprotein Detection Based on Oligonucleotide Chain Functionalized Magnetic Graphene Oxide and Co-Catalyzed Copper-Based Organic Framework Composites

Fe3O4@HKUST-1 magnetic composites by mechanochemical route for induction triggered release of carbon dioxide

HKUST-1 metal-organic framework (MOF) and Fe3O4@HKUST-1 magnetic framework composites (MFCs) were developed by a simple and sustainable liquid assisted mechanochemical synthesis process. The growth of the MOF crystalline structure was directed on the surface of functionalized magnetite particles, which act as “crystallization germs”. The nanomaterials were characterized in their structural, morphological, and thermal properties and were tested for CO2/N2 mixture separation. All samples exhibits good carbon dioxide adsorption and selectivity for the CO2/N2 mixture. In the case of magnetic composites, the application of an external alternating magnetic field induces nanoparticles’ heating and the locally generated heat triggers carbon dioxide release from the MOF. The magnetic composites combine the adsorbing properties of the organic component and the heating capacity of magnetic nanoparticles, MNPs, representing innovative sorbent systems for the implementation of a separation technology named Magnetic Induction Swing Adsorption (MISA). This technology takes advantage of the highly efficient energy transfer typical of induction heating for the regeneration of adsorption beds and promises energy savings. The effectiveness of the desorption process depends on the magnetic materials properties and in this work has been improved by tuning the characteristic of the magnetic component.

Fe3O4@MOF Magnetic Nanocomposites: Synthesis and Applications

In this review, we gather a great deal of information about magnetic nanocomposites, which are made from the combination of Fe3O4 magnetic nanoparticles (MNPs) and metal‐organic frameworks (MOFs). Due to the high saturation magnetization, biocompatibility, low toxicity, stability, and cost‐effectiveness, MNPs have attracted a lot of interest in recent years. Furthermore, MOFs, which are porous materials, formed by the connection between organic linkers and metal ions. The combination of MNPs and MOFs results in the formation of magnetic framework composites (MFCs). The information about the MFCs is classified according to their applications and we provide brief information about the synthesizing of these materials. MFCs have a wide array of uses in various fields such as catalysis, biomedical, extraction, etc. We discussed these applications in detail. This information has been amassed to provide researchers with a proper chance to obtain enough information about these materials. Researchers are also able to become aware of some drawbacks in each field, and they can propose some solutions to overcome those drawbacks. We aimed to prepare a well‐organized review to respond to the desire of using MFCs in different fields.

Facile synthesis of guanidyl-based magnetic ionic covalent organic framework composites for selective enrichment of phosphopeptides

Protein phosphorylation plays vital roles in the regulation of various biological processes involving in protein folding, molecular recognition, cell growth, and metabolism. It is prerequisite to develop effective enrichment methods of trace phosphopeptides before mass spectrometry (MS) analysis. In this study, we proposed a facile strategy to synthesize magnetic ionic covalent organic frameworks (Fe3O4@iCOFs) for the capture of phosphopeptides with guanidyl as the ionic ligand instead of the post-synthetic functionalization strategy. The developed Fe3O4@iCOFs contain a large amount of amino groups, positive charge, as well as owned superparamagnetism. The enrichment of phosphopeptides is based on the electrostatic interaction and hydrogen bonds formed between phosphate groups and guanidyl groups. By combing with MS determinations, high sensitivity of phosphopeptides (the lowest detection amount being 0.4 fmol) was achieved. The obtained material provided selective enrichment capacity of phosphopeptides from non-fat milk digest and HeLa cells, showing great potential in the detection of low-abundance phosphopeptides in complex real samples.

Recent Advances in Preparation and Applications of Magnetic Framework Composites.

Metal-organic frameworks (MOFs) offer ample characteristics, such as easy synthesis, high surface area, tunable porosities, open metal sites, post-synthesis modification, making them attractive for diverse applications. Since magnetic particles can be positioned and separated by a magnetic field, magnetic framework composites (MFCs) have attracted tremendous attention. In this review, different methods of preparing MFCs, including direct mixing, in-situ growth of magnetic particles, embedding method, layer-by-layer growth method and encapsulation method, will be discussed in detail. Moreover, their applications in catalysis, adsorption, biomedicine and sensing will also be introduced.

Magnetic Zink-based metal organic framework as advance and recyclable adsorbent for the extraction of trace pyrethroids

Core-shell structured magnetic framework composites (Fe3O4@TMU-21) were fabricated via a facile approach and applied as an effective adsorbent for magnetic solid-phase extraction (MSPE) of trace pyrethroid residues from fruit juice samples. Magnetic framework composites (MFCs) were synthesized via a step-by-step assembly, novel, simple and efficient strategy. The fabricated MFCs showed a high magnetization saturation, accessible sites and good adsorption performance. By coupling MSPE with high-performance liquid chromatography–ultraviolet detection (HPLC-UV), a simple, fast, sensitive, reliable, and cost-effective method for simultaneous determination of trace pyrethroid residues was established successfully. Under optimal conditions, excellent linearity was obtained in the range of 0.5–250 μg L−1, with correlation coefficients R2 > 0.99 and the limits of detection was ranged between 0.1 and 0.05 μg L−1 (based on S/N = 3). Preconcentration factors (PF) and relative recoveries (RR) of the target analytes were obtained in the range of 463–498 and 93.0–104.5% respectively. The precision of the method expressed as a relative standard deviation (RSD) for extraction and determination of the 100 μg L−1 pyrethroid residues in the samples solution was in the range of 3.1–4.4%. The results demonstrate that magnetic Fe3O4@TMU-21 core-shell are the promising sorbents for rapid and efficient extraction of pyrethroid residues from fruit juice samples.

Microwave assisted magnetic solid phase extraction using a novel amino-functionalized magnetic framework composite of type Fe3O4-NH2@MIL-101(Cr) for the determination of organochlorine pesticides in soil samples

In this research, microwave assisted magnetic solid phase extraction (MAE-MSPE) coupled with GC-ECD have been successfully used for the determination of eight organochlorine pesticides in soil samples. Specially, the novel Fe3O4-NH2@MIL-101(Cr) composites as the MSPE sorbent played a role of selective enrichment and purification towards the targets. The MAE-MSPE procedure was optimized focusing on microwave extraction temperature and time, solution pH, the amount of sorbent, ultrasonic extraction time, ionic strength, elution solvent type, elution solvent volume, and elution time. The parameters of the analytical method were evaluated. Under the optimal condition, the detection limits of α-HCH, β-HCH, γ-HCH, δ-HCH, p,p′-DDE, p,p′-DDD, o,p′-DDT, and p,p′-DDT were in the range of 0.15–0.28 ng g−1. Satisfactory recoveries were obtained in the range of 71.2–102.4% with the RSDs less than 10.0%. The obtained results demonstrated that the method was suitable for the trace analysis of OCPs. Additionally, molecular docking was employed to calculate the molecular interactions and free binding energies between MIL-101(Cr) and the organochlorines.

Recent progress in nanostructured magnetic framework composites (MFCs): Synthesis and applications

Abstract The highly ordered porosity of metal organic frameworks (MOFs), constructed from different organic binding ligands and metal ions, render exceptional chemical and physical properties suitable for an array of applications in different domains. Recently, these materials have been employed to functionalize nanoparticles for the development of magnetic framework composites (MFCs). This fascinating class of MOFs aims to amalgamate the intrinsic properties of MOFs with the benefits of magnetic property to further accentuate their performance and broaden the applications. Specifically designed MFCs offer novel properties such as devisable composition, large surface area, easy loading and rapid collection. This review presents a holistic insight into efficient strategies for fabricating MFCs such as non-core-shell and core-shell methods. Further, the recent progress of MFCs in the areas of separation/treatment processes for dye, heavy metal, pollutants from a variety of wastewater is exploited. In the field of catalysis, MFCs not only act as photocatalysts but also provide a platform for utilizing noble metals and enzymes. This facilitates their easy separation from the reaction mixture. Effort is warranted in providing a balanced outline of the application of MFCs for extraction and biomedical applications.

Magnetic framework composite as sorbent for magnetic solid phase extraction coupled with high performance liquid chromatography for simultaneous extraction and determination of tricyclic antidepressants

In this study, magnetic framework composites (MFCs) (Fe3O4@TMU-10) microspheres were successfully fabricated and applied as an effective sorbent for preconcentration of the two model tricyclic antidepressants (TCAs) amitriptyline and imipramine from biological samples. MFCs were fabricated by a step-by-step assembly, novel, simple and efficient strategy. The shell thickness of the Metal-organic frameworks (MOFs) could also be easily controlled by tuning the number of assembly cycles. By coupling magnetic solid-phase extraction (MSPE) with high-performance liquid chromatography with UV detector (HPLC-UV), a simple, reliable, fast, sensitive and cost-effective method for simultaneous determination of TCAs was developed. Under optimal conditions, the preconcentration factors and relative recoveries of the studied compounds were obtained in the range of 43–50 and 90.5–99.0% respectively. The calibration curves were obtained in the range of 5–800 μg L−1 with reasonable linearity (R2 > 0.9904) and the limits of detection (LODs) ranged between 2 and 4 μg L−1 (based on S/N = 3). The relative standard deviations of intra- and inter-day tests ranged from 3.1 to 4.6% and from 4.3 to 5.2%, respectively. The results demonstrate that Fe3O4@TMU-10 core–shell magnetic microspheres combine advantages of MOFs and magnetic nanoparticles, and are the promising sorbents for rapid and efficient extraction of target analytes from urine and plasma complex biological samples.

Magnetic Framework Composites for Low Concentration Methane Capture

This study proposes a simple and energy efficient technique for methane (CH4) capture from low concentration emission sources. An extrusion-based process was used to fabricate magnetic framework composites (MFCs) from a metal organic framework (MOF), aluminum fumarate, and MgFe2O4 magnetic nanoparticles (MNP). Methane uptake for MFCs with different MNP loading at 1 bar and 300 K revealed a high methane uptake of up to 18.2 cm3 g–1. To regenerate the MFCs, a magnetic induction swing adsorption (MISA) process was applied. A working capacity of 100% was achieved for the MFC over 10 adsorption–desorption cycles with an average of 6 min per cycle for the regeneration step. The ability to access 100% of the adsorbed CH4 in the MFC with rapid and localized heating achieved with the MISA process potentially provides an energy efficient technique for CH4 capture and reuse from low concentration sources.

Magnetic Metal-Organic Framework Composite by Fast and Facile Mechanochemical Process.

Magnetic porous metal-organic framework nanocomposite was obtained by an easy, efficient, and environmentally friendly fabrication method. The material consists in magnetic spinel iron oxide nanoparticles incorporated in an iron(III) carboxylate framework. The magnetic composite was fabricated by a multistep mechanochemical approach. In the first step, iron oxide nanoparticles were obtained via ball milling inducing mechanochemical reaction between iron chlorides and NaOH using NaCl as dispersing agent. Magnetic nanoparticles (MNs) were functionalized by neat grinding with benzene-1,3,5-tricarboxylic acid (1, 3, 5 BTC) and were then subjected to liquid assisted milling using hydrated FeCl3, water, and ethanol to obtain a magnetic framework composite (MFC) consisting of iron oxide nanoparticles encapsulated in a MOF matrix. We report, for the first time, the applicability of the grinding method to obtain a magnetic composite of metal-organic frameworks. The synthesized material exhibits magnetic characteristics and high porosity, and it has been tested as carrier for targeted drug delivery studying loading and release of a model drug (doxorubicin). Developed systems can associate therapeutics and diagnostics properties with possible relevant impact for theranostic and personalized patient treatment. Furthermore, the material properties make them excellent candidates for several other applications such as catalysis, sensing, and selective sequestration processes.

An amino-functionalized magnetic framework composite of type Fe3O4-NH2@MIL-101(Cr) for extraction of pyrethroids coupled with GC-ECD.

An amino-functionalized magnetic framework composite of type Fe3O4-NH2@MIL-101(Cr) was synthesized using a solvothermal method. The material was characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption, and magnetometry. The composite combines the advantages of amino-modifiedFe3O4 and MIL-101(Cr). The presence of amino groups facilitates the fairly specific adsorption of pyrethroids. The composite was employed as a sorbent for magnetic solid phase extraction of five pyrethroids from environmental water samples. Following desorption with acidified acetone, the pyrethroids were quantified by gas chromatography with electron capture detection. The detection limits for bifenthrin, fenpropathrin, λ-cyhalothrin, permethrin, and deltamethrin range from 5 to 9pg·mL-1. The method is rapid, accurate, and highly sensitive. The molecular interactions and free binding energies between MIL-101(Cr) and the five pyrethroids were calculated by means of molecular docking. Graphical abstract A novel functionalized magnetic framework composite of typeFe3O4-NH2@MIL-101(Cr) was synthesized. It was applied as a sorbent for magnetic solid phase extraction of pyrethroids prior to their quantitation by gas chromatographywithelectron capture detection. The molecular interactions of analytes and MIL-101(Cr) were studied.

Towards energy efficient separations with metal organic frameworks.

The huge energy requirement for industrial separations of chemical mixtures has necessitated the need for the development of energy efficient and alternative separation techniques in order to mitigate the negative environmental impacts associated with greenhouse gas emissions from fossil fuel combustions for energy generation. A promising approach involves the use of magnetic framework composites (MFCs) for gas capture and release via localised magnetic induction heating in a process known as magnetic induction swing adsorption (MISA). This feature article presents an overview of the mechanism of induction heating of magnetic nanoparticles, incorporation of the nanoparticles into metal organic frameworks to form MFCs and the potential of deploying MFCs for the mitigation of greenhouse gas emissions using the MISA process. We also present an overview of the potential energy savings as a result of the efficiency of magnetic induction heating and we give a perspective on the future directions in material and process development that could lead to widespread deployment of the MISA process for industrial separation operations.