Magnetic Porous Organic Polymer Research Articles

Novel magnetic porous organic polymer containing amino and triazine bifunctional groups for efficient adsorption of nitroimidazoles

In this paper, a novel magnetic hyper-crosslinked polymer with amino and triazine bifunctional groups (M-NH2-THCP) was developed. M-NH2-THCP has strong nitroimidazoles (NDZs) enrichment effect, and therefore it was used as an adsorbent to extract five NDZs from lake water, catfish and shrimp meat prior to HPLC. Polar interaction, π-π stacking interaction, hydrogen bond and Lewis acid-base interaction were attested to be the major adsorption mechanism. The method has a good linearity in the range of 0.1–100 ng mL−1 for lake water, 10–400 ng g−1 for catfish and shrimp muscle with R2 > 0.9964. The limits of detection of NDZs were 0.03–0.04 ng mL−1 for lake water, 1.0–2.0 ng g−1 for catfish and 2.0–2.5 ng g−1 for shrimp, which is superior to most reported method. The method recoveries were 87.6–119 %, and relative standard deviations were less than 8.7 %. M-NH2-THCP holds great application potential in pollutants enrichment, separation and removal.

Facile synthesis of multifunctional magnetic porous organic polymers with high catalytic performance and dye adsorption capacity

Multifunctional magnetic porous organic polymers (MOPs) rich in sulfide and free phenolic hydroxyl groups were synthesized. The MOPs exhibit a large surface area and can interact strongly with metal ions and cationic dyes, including methylene blue.

Magnetic phosphazene porous organic polymer for efficient and selective recovery of rare earth elements from acidic wastewater

Efficient recovery of rare earth elements (REEs) from secondary resources is highly recommended to meet industrial production demand and maximize resource utilization. Herein, a magnetic porous organic polymer, termed MTAP, was developed by choosing natural polyphenol tannic acid as a monomer and hexachlorocyclotriphosphazene as a crosslinker. The integration of magnetic nanoparticles further enhanced its advantages since it can be rapidly isolated using an external magnetic field, simplifying the overall operation. Batch adsorption experimental results showed that MTAP can quickly capture REEs including Ce, Nd, Eu, and Gd, achieving the adsorption equilibrium just in 2 min. Furthermore, the adsorption isotherms exhibited an excellent fit with the Langmuir model with the maximum adsorption capacities ranging from 145.5 to 164.2 mg/g at 25 °C. What’s more, MTAP was successfully applied to recycle REEs in industrial wastewater with high recovery efficiencies. These characteristics including low cost, easy preparation, rapid adsorption kinetics, and high adsorption capacities highlight the outstanding application prospects of MTAP for the recovery of REEs.

Synthesis of amine-functionalized magnetic porous organic polymers for effective extraction of phenolic endocrine disrupting chemicals

Amine-functionalized porous organic polymers (EDA-POP-PC and EDA-POP-BT) were prepared by post-modification of POP-PC and POP-BT with ethylenediamine (EDA) for the first time. The POP-PC and POP-BT were obtained through Friedel-Crafts acylation reaction of potassium tetraphenylborate with p-phthaloyl chloride (PC) and 1,3,5-benzenetricarbonyl trichloride (BT), respectively. The EDA-POPs exhibited superior adsorption capacity for phenolic endocrine disrupting chemicals (EDCs). After magnetically functionalization, the obtained M-EDA-POP-PC was employed as a magnetic adsorbent for enrichment of phenolic EDCs from real samples prior to high performance liquid chromatography-ultraviolet detection. The current strategy showed low detection limits (S/N = 3) of 0.02–0.07, 0.04–0.08 and 0.04–0.10 ng mL−1 for river water, white peach juice and lychee juice, respectively. The method recoveries were 81.7%–115% with relative standard deviations below 8.6%. The proposed strategy showed good practicality for sensitive determination of phenolic EDCs in real samples.

Synthesis of phosphate-functionalized magnetic porous organic polymer: A sorbent for sensitive determination of neonicotinoid insecticides in water and lemon juice

There is an urgent need to prepare advanced functional materials for extraction and enrichment of trace organic pollutants from different samples. In this work, two novel phosphate-functionalized porous organic polymers (DBP-POP and DPP-POP) were synthesized for the first time. Compared with phosphate-free counterpart, both phosphate-functionalized POPs showed excellent adsorption performance for the neonicotinoids due to the hydrogen bonding, π-π interaction and hydrophobic interaction. For ease of separating the sorbent from solution, magnetic DBP-POP (M-DBP-POP) was further prepared as sorbent to extract neonicotinoids from environmental water and lemon juice samples prior to their determination by high performance liquid chromatography-ultraviolet detection. Under optimal conditions, the detection limits (S/N = 3) of the method were 0.01–0.08 ng mL−1 for water and 0.03–0.10 ng mL−1 for lemon juice. The recoveries were in the range of 80.0% to 113.0% with relative standard deviation less than 10.6%. This work demonstrated the feasibility of phosphate-functionalized POPs for adsorption applications.

Fabrication of a Magnetic Porous Organic Polymer for α-Glucosidase Immobilization and Its Application in Inhibitor Screening

The technology based on immobilized enzymes was employed to screen the constituents inhibiting disease-related enzyme activity from traditional Chinese medicine, which is expected to become an important approach of innovative drug development. Herein, the Fe3O4@POP composite with a core-shell structure was constructed for the first time with Fe3O4 magnetic nanoparticles as the core, 1,3,5-tris (4-aminophenyl) benzene (TAPB) and 2,5-divinylterephthalaldehyde (DVA) as organic monomers, and used as the support for immobilizing α-glucosidase. Fe3O4@POP was characterized by transmission electron microscopy, energy-dispersive spectrometry, Fourier transform infrared, powder X-ray diffraction, X-ray photoelectron spectroscopy, and vibrating sample magnetometry. Fe3O4@POP exhibited a distinct core-shell structure and excellent magnetic response (45.2 emu g-1). α-Glucosidase was covalently immobilized on core-shell Fe3O4@POP magnetic nanoparticles using glutaraldehyde as the cross-linking agent. The immobilized α-glucosidase possessed improved pH stability and thermal stability as well as good storage stability and reusability. More importantly, the immobilized enzyme exhibited a lower Km value and enhanced affinity for the substrate than the free one. The immobilized α-glucosidase was subsequently used for inhibitor screening from 18 traditional Chinese medicines in combination with capillary electrophoresis analysis among which Rhodiola rosea exhibited the highest enzyme inhibitory activity. These positive results demonstrated that such magnetic POP-based core-shell nanoparticles were a promising carrier for enzyme immobilization and the screening strategy based on immobilized enzyme provided an effective way to rapidly explore the targeted active compounds from medicinal plants.

Porphyrin-based magnetic porous organic polymer for efficient magnetic solid phase extraction of nonsteroidal anti-inflammatory drugs from water

The ubiquitous occurrence of nonsteroidal anti-inflammatory drugs (NSAIDs) in the environmental water system has drawn significant concerns due to their adverse effects. The accurate monitoring the content of them is of great significance but challenging in terms of the complex matrix and trace concentration. In this work, a porphyrin-based magnetic porous organic polymer composite (PM-POP) was prepared through a solvent-free synthetic method. Owing to the highly porous structure and strong affinities, the as-prepared PM-POP could be utilized as a highly efficient adsorbent for the magnetic solid phase extraction (MSPE) of NSAIDs. Combining with the high-performance liquid chromatography separation with ultraviolet detector (HPLC-UV), a sensitive analytical method was established, which exhibited wide linear ranges (0.1–400 μg/L) and large enrichment factors (EFs) (39.5–82.9 folds) along with good precision (intra-day RSD ≤ 4.9%) and repeatability (inter-day RSD ≤ 8.4%). Ultimately, it was applied to determinate trace NSAIDs in practical water samples successfully, demonstrating its good application prospect in environmental analysis.

Developing a hydroxyl-functionalized magnetic porous organic polymer combined with HPLC-MS/MS for determining 31 amide herbicides in fruit wine

More and more attention has been paid to undesirable chemical contaminants from food raw materials and ingredients. The study aimed to fabricate novel hydroxyl-functionalized magnetic porous organic polymer Fe3O4@SiO2-NH2@Ph-POP and explore its use as magnetic adsorbents for magnetic solid-phase extraction (MSPE) for extracting 31 amide herbicides from fruit wine samples prior to high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Several operational parameters were optimized and the as-prepared magnetic polymer displayed favorable extraction efficiency. The method also showed low limits of detection (0.015–1.412 μg·L-1) and limits of quantitation (0.049–4.707 μg·L-1). Recoveries for all of the herbicides in four different spiked level samples were between 65.06 % and 101.95 % with intra-day and inter-day relative standard deviations less than 9.89 % and 10.54 %, respectively. The proposed MSPE-HPLC-MS/MS method was successfully applied to simultaneously determine 31 amide herbicides in fruit wine.

Facile green synthesis of magnetic porous organic polymers for fast preconcentration of trace lead and mercury from environmental water followed by graphite furnace atomic absorption spectrometry detection

Magnetic porous organic polymers (MPOPs) was synthesized in aqueous phase under mild condition by using Fe3O4@SiO2 nanoparticles as magnetic core, 1,3,5-tris-(4-aminophenyl) benzene (TAPB) and 4-(2-pyridylazo) resorcinol (PAR) as two building blocks. The resultant materials (denoted as TAPB-PAR-MPOPs) have the features of good magnetism, high porosity and large surface area, and fast adsorption kinetic (8 min) as well as high adsorption capacities (319 and 374 mg g−1, respectively) toward lead and mercury ions. With the prepared TAPB-PAR-MPOPs as sorbent, a method of magnetic solid phase extraction coupled with graphite furnace atomic absorption spectrometry was developed for the determination of trace lead and mercury in environmental water samples. Under the optimal conditions, the detection limits were 0.009 and 0.017 μg L−1 for lead and mercury, respectively. The developed method was successfully applied to the analysis of trace lead and mercury in tap water, lake water and river water samples with satisfactory recoveries (88.3–107%), demonstrating a good potential of TAPB-PAR-MPOPs in extraction of trace lead and mercury in environmental waters.

Green synthesis of novel magnetic porous organic polymer for magnetic solid phase extraction of neonicotinoids in lemon juice and honey samples

Natural rutin with abundant hydroxyl groups was used as a green monomer to synthesize hydroxyl-functional magnetic porous organic polymer (named Rut-MOP) through environmentally-benign diazo-coupling reaction for the first time. The Rut-MOP displayed high extraction capability for neonicotinoid insecticides (thiamethoxam, imidacloprid, acetamiprid and thiacloprid). Thus, a Rut-MOP based magnetic solid-phase extraction method combined with high performance liquid chromatography was established for sensitive determination of neonicotinoid insecticides in lemon juice and honey samples. Under optimized conditions, the linear response of neonicotinoids was 0.1–100.0 ng mL−1 for lemon juice and 8.0–1000.0 ng g−1 for honey. The limits of detection (S/N = 3) were 0.03–0.04 ng mL−1 and 2.5–3.0 ng g−1 for lemon juice and honey, respectively. The method recoveries were 82–118% with the relative standard deviations of 1.9–7.6%. The results demonstrate that the Rut-MOP based method can be served as a good alternative for the sensitive analysis of neonicotinoid insecticides in lemon juice and honey.

A magnetic porous organic polymer: catalytic application in the synthesis of hybrid pyridines with indole, triazole and sulfonamide moieties.

Herein, the synthesis and characterization of a triazine-based magnetic ionic porous organic polymer are reported. The structure, morphology, and components of the prepared structure have been investigated with several spectroscopic and microscopic techniques such as FT-IR, EDX, elemental mapping, TGA/DTA, SEM, TEM, VSM, and BET analysis. Also, catalytic application of the prepared triazine-based magnetic ionic porous organic polymer was investigated for the synthesis of hybrid pyridine derivatives bearing indole, triazole and sulfonamide groups. Furthermore, the prepared hybrid pyridine systems were characterized by FT-IR, 1H NMR, 13C NMR and mass analysis. A cooperative vinylogous anomeric-based oxidation pathway was suggested for the synthesis of target molecules.

Amino-functionalized magnetic porous organic polymer for the selective removal of toxic cationic dyes from textile wastewater

An amino-functionalized magnetic porous organic polymer (POP) was synthesized through the Friedel–Crafts reaction for selective adsorption of cationic dyes from aqueous solution.

Core-shell magnetic porous organic polymer for magnetic solid-phase extraction of fluoroquinolone antibiotics in honey samples followed by high-performance liquid chromatography with fluorescence detection.

By monomer-mediated in-situ growth synthesis strategy, with hydroquinone and 1,3,5-tris(4-aminophenyl)benzene as monomers, a core-shell magnetic porous organic polymer was synthesized through a simple azo reaction. Based on this, a magnetic solid-phase extraction-high-performance liquid chromatography-fluorescence detection method was proposed for the analysis of fluoroquinolones in a honey sample. With ofloxacin, ciprofloxacin, enrofloxacin, lomefloxacin, and difloxacin as target analytes, factors affecting the extraction efficiency had been optimized. The LODs were 1.5-5.4ng/L (corresponding to 0.23-0.81μg/kg in honey). The linear range was 0.005-20 μg/L for difloxacin, 0.01-20 μg/L for ofloxacin, ciprofloxacin and lomefloxacin, and 0.02-20 μg/L for enrofloxacin. The enrichment factor was 84.4-91.7-fold with a high extraction efficiency of 84.4-91.7%. The method was assessed by the analysis of target fluoroquinolones in honey samples, and the recoveries for the spiked samples were 79.3-95.8%. The results indicated that the established magnetic solid-phase extraction-high-performance liquid chromatography-fluorescence detection method is efficient for the analysis of trace fluoroquinolones in honey.

Synthesis of urea-functionalized magnetic porous organic polymers Fe3O4@PDA@UPOPs for rapid extraction of fluoroquinolones in food samples

It is of great interest in the development of reliable strategies for efficient adsorption and enrichment of drug residues in sample pretreatment. In this paper, urea-based porous organic polymers (UPOPs) were synthesized by the atom economic polymerization reaction of 1,4-phenylene diisocyanate (PPDI) and 1,3,5-tris(4-aminophenyl)benzene (TAPB) under mild conditions. Inspired by the versatility of polydopamine (PDA) coating, the UPOPs were successfully decorated on PDA coated-magnetic nanoparticles (Fe 3 O 4 @PDA) via in situ catalyst-free polymerization to afford urea-functionalized porous organic polymers (Fe 3 O 4 @PDA@UPOPs). The synthesized adsorbents exhibited good stability, high hydrophicility, microporous and mesoporous structure. The applicability of Fe 3 O 4 @PDA@UPOPs was evaluated as effective adsorbents for the magnetic solid-phase extraction (MSPE) of fluoroquinolones (FQs) from food samples (milk, egg and chicken muscle). Combined with high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) analysis, the optimized method featured low adsorbents dosage (2 mg) and rapid extraction (2 min), which provided a wide linear range (0.1–200.0 ng/g, r ≥ 0.9991) and high sensitivity (LODs: 0.04–0.1 ng/g) for FQs determination. Furthermore, controllable magnetism enable the adsorbents could be easily recovered by external magnet and reused at least eight extraction cycles without decreasing the adsorption performance. • Urea-functionalized magnetic porous organic polymers (Fe 3 O 4 @PDA@UPOPs) were fabricated under mild conditions. • The functionalized magnetic adsorbents were characterized by FT-IR, SEM, XRD and TGA analysis. • Application of Fe 3 O 4 @PDA@UPOPs in MSPE-HPLC-MS/MS for fluoroquinolones (FQs) analysis was developed. • The established method is sensitive and efficient with low adsorbent dosage for the detection of FQs.

Preparation of functional magnetic porous organic polymer as sorbent for mercury speciation followed by HPLC-ICP-MS analysis

The sulfur containing functional magnetic porous organic polymer based MSPE-HPLC-ICP-MS shows high enrichment factor and low detection limits for mercury speciation.

Carboxyl-functionalized magnetic porous organic polymers as efficient adsorbent for wastewater remediation

Decontamination of toxic pollutants by porous nanomaterials with high removal efficiency has aroused immense concern in recent years. Herein, the newly designed magnetic porous organic polymers with abundant carboxyl groups (CMPOPs) were prepared via a facile in-situ surface polymerization strategy and their adsorption performance towards malachite green (MG) in aquaculture wastewater was investigated. The strong interactions between CMPOPs and malachite green, especially the strong electrostatic interaction between carboxyl groups and target molecules, were favorable for adsorption, where the maximum adsorption capacity of CMPOPs was in the range of 569.4–779.1 mg g−1. Furthermore, the contaminant in aqueous solutions can be adsorbed within 2 min when the initial concentration was 100.0 mg L−1. Apart from their superior adsorption performance, the easy separation feature and excellent regeneration property of CMPOPs rendered them to become an alternative adsorbent for toxic contaminant removal from aquaculture wastewater.

Magnetic porous organic polymers for extraction of cardiovascular drugs in human urine samples followed by HPLC-UV

Prepared magnetic porous organic polymers show high extraction efficiency towards cardiovascular drugs.

Feasibility of toxic metal removal from aqueous medium using Schiff-base based highly porous nanocomposite: Adsorption characteristics and post characterization

Fabrication of novel adsorbent with high surface area and high adsorption capacity is in urgent demand for water treatment, Therefore, in this study, a nanocomposite include Schiff base polymer and magnetic Fe3O4 nanoparticles was synthesized and characterized using analytical techniques including FTIR, TGA, XRD, Raman, SEM, TEM, XPS and N2 adsorption-desorption studies. The fabricated magnetic porous organic polymer (MPOP) was used as an efficient adsorbent for the removal of Cd(II) and Hg(II) from aqueous solution. The adsorption kinetic results revealed that both metal ions; Cd(II) and Hg(II) supported the pseudo-second-order adsorption kinetic model. The Langmuir isotherm model supported the adsorption over MPOP with a maximum adsorption capacity of 308.9 mg g−1 and 284.6 mg g−1 for Cd(II) and Hg(II), respectively. The thermodynamic results indicated that the adsorption of both metal ions was spontaneous and endothermic. The regeneration results suggested that the novel MPOP was a promising reusable adsorbent for the adsorption of heavy metal ions from aqueous solution.

Ultrafine palladium nanoparticles confined in core–shell magnetic porous organic polymer nanospheres as highly efficient hydrogenation catalyst

The development of porous organic polymer (POP)-based materials with controllable structures is highly desirable for catalysis, drug delivery, and chemical adsorption. In this work, we prepared unique porous magnetic core–shell POP nanospheres (Fe3O4@PDA@POP) through a facile strategy. These nanospheres contained a core of magnetic Fe3O4 nanoparticles (NPs), a hydrophilic intermediate layer of dopamine and a POP outer layer. The Fe3O4@PDA@POP showed high porosity, making it an ideal supporting material for fabricating ultrafine and highly dispersed noble-metal NPs (NMNPs). Thus, highly dispersed ultrafine Pd NPs (1.5–2.1 nm) were confined and stabilized within the pores of Fe3O4@PDA@POP via a reverse double-solvent approach (RDSA) to obtain Fe3O4@PDA@POP@Pd catalyst. The Fe3O4@PDA@POP@Pd-2.5% catalyst showed excellent catalytic performance and recyclability towards the hydrogenation of nitrobenzene, alkenes, and alkynes. Hence, this work can pave the way for the development and application of functionalized POP materials to construct efficient catalytic systems.

Magnetic porous organic polymers for magnetic solid-phase extraction of triazole fungicides in vegetables prior to their determination by gas chromatography-flame ionization detection

Magnetic porous organic polymers (MOPs) were synthesized by a simple azo reaction, with 1,3,5-tris (4-aminophenoxy) benzene and 1,3,5-trihydroxybenzene as the monomers, and Fe3O4@SiO2 as the core. The preparation process was mild, green and environmental-friendly, avoiding the use of high temperature, metal catalysis and harmful organic reagent. The obtained MOPs were characterized in terms of morphology, pore structure, and magnetism; they exhibited high surface area, good stability/dispersibility, and excellent extraction performance for interest triazole fungicides (TFs). With the prepared MOPs as adsorbent, a method of magnetic solid phase extraction-gas chromatography-flame ionization detection (MSPE-GC-FID) was proposed for the analysis of target TFs in vegetables. After the vegetable samples were chopped and homogenized, acetonitrile was added for ultrasonic extraction, and the extract was diluted for subsequent MSPE process. Different operating conditions affecting the extraction efficiency of TFs, such as extraction time, pH, ionic strength, adsorbent dosage, and volume of sample as well as eluent were carefully optimized. Under the optimized experimental conditions, quantitative extraction could be achieved for target TFs (extraction efficiency of 84.5–90.3%), and the limits of detection were in the rage of 0.12–0.19 μg/L, which is the lowest among the reported GC-FID methods for target TFs presently. The linear range of the method for five TFs was 0.5–200 μg/L with the reproducibility of 2.6–6.8% (n = 7, c = 2 μg/L). The method was assessed by the analysis of target TFs in vegetables, and the recoveries for the spiked cucumber and cabbage were 86.9–117% and 84.7–114% (spiking levels of 80, 400 and 800 μg/kg), respectively, indicating that the matrix effect was negligible in the proposed MSPE procedure. The results show that the developed method of MSPE-GC-FID with MOPs as adsorbent is efficient for the analysis of trace TFs in vegetables.