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Bisphenols (BPs) can migrate from packaging materials into foods, resulting in potentially harmful residues. For example, accumulation of BPs is associated with endocrine disorders. Owing to matrix effects, development of an effective and eco-friendly sample pretreatment would be helpful for BPs detection in beverages packed in plastic containers. In this work, an extraction bar, composed of hollow fiber (HF) functionalized with covalent organic frameworks (COF@Tp-NDA) and 1-ocanol, was prepared for extraction of five BPs simultaneously. The synergistic effect of COF@Tp-NDA and 1-octanol improved the extraction efficiency of BPs from milk-based beverage, juice, and tea beverage. Under optimal conditions, limits of detection ranged from 0.10 to 2.00 ng mL -1 (R 2  ≥ 0.9974) and recoveries ranged from 70.1 % to 106.8 %. This method has the potential to enrich BPs, supporting their accurate determination in complex beverages., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Neonicotinoids, the fastest-growing class of insecticides, have posed a multi-media residue problem with adverse effects on environment, biodiversity and human health. Herein, covalent organic framework-sodium alginate-Ca 2+ -polyacrylic acid composite beads (CACPs), facilely prepared at room temperature, were used in convenient dispersive solid-phase extraction (dSPE) and combined with high-performance liquid chromatography (HPLC) for the detection of five neonicotinoid insecticides (thiamethoxam, acetamiprid, dinotefuran, clothianidin, imidacloprid). CACPs can be completely separated within 1 min without centrifugation. After seven adsorption/desorption cycles, it maintained high extraction efficiencies (>90%). The developed method exhibited a wide linear range (0.01 ∼ 10 μg mL -1 ), low limits of detection (LODs, 0.0028 ∼ 0.0031 mg kg -1 ), and good repeatability (RSD ≤ 8.11%, n = 3). Moreover, it was applied to the determination of five neonicotinoids in fruit and vegetables (peach, pear, lettuce, cucumber, tomato), and recoveries ranged from 73.6% to 116.2%., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The presence of estrogens residues in dairy products is a growing concern due to their potential health risk. Herein, in this study, we have developed a membrane-protected magnetic solid-phase extraction (MP-MSPE) method that utilized a magnetic adsorbent (Fe 3 O 4 @COF-LZU1) with in-situ growth for the efficient extraction of estrone (E1), 17β-estradiol (E2), and estriol (E3). When combined with HPLC-FLD, this method allows for the efficient detection of estrogens in dairy products. The stability of the MP-MSPE was improved by the presence of a dialysis membrane, which remained a high extraction efficiency (90 %) even after ten reuse cycles. The hydrogen bonding, π-π interactions and pore size effect contribute to the excellent adsorption of three estrogens onto Fe 3 O 4 @COF-LZU1. Under optimal conditions, the method exhibits a low detection limit (0.01-0.15 μg L -1 ), wide linear range (0.1-800 μg L -1 ), and favorable recoveries (77.3 %-109.4 %) at three concentration levels (10, 50 and 100 μg L -1 ). This proposed method is characterized by its simplicity, high efficiency and eco-friendliness, making it a promising approach for extracting estrogens from dairy products., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Triazole is frequently-used fungicide, which can leach into surface water through farmland and cause serious environmental pollution. Continuous exposure to triazole fungicides may cause harm to human health. Herein, β-cyclodextrin-polyacrylamide/covalent organic framework (β-CD-PAAM/TFPB-BD) hydrogel was fabricated at room temperature and used for the efficient removal of triazole fungicides. It displayed a short adsorption equilibrium time (50 min) and a total q e of 79.92 mg g -1 . The adsorption process for triazole fungicides on β-CD-PAAM/TFPB-BD hydrogel conforms to the pseudo-second-order kinetic model and Freundlich model. The prepared hydrogel was recyclable and resistant to salt, high temperature, acid, and alkali. The reusability of fabricated sorbent can be achieved (i.e., five extraction cycles) for removal of target fungicides. Moreover, the β-CD-PAAM/TFPB-BD hydrogel was successfully applied to remove triazole fungicides in environmental water with removal efficiency ranging from 79.4% to 99.0%., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

As glyphosate is a broad-spectrum herbicide extensively used in agriculture worldwide, rapid glyphosate detection is essential for food safety and human health. Herein, a ratio fluorescence test strip was prepared and coupled with an amino-functionalized bismuth-based metal-organic framework (NH 2 -Bi-MOF) that bonded with copper ion for rapid visualization and determination of glyphosate. NH 2 -Bi-MOF had excellent fluorescence performance, and the copper ion, a Lewis acid, was selected as the quencher. The strong chelation of glyphosate with copper ion and its quick interaction with NH 2 -Bi-MOF would turn on the fluorescence signal, thus enabling the quantitative sensing of glyphosate, with a linear range of 0.10-200 µmol L -1 , and recoveries between 94.8% and 113.5%. The system was then expanded to a ratio fluorescence test strip, in which the fluorescent ring sticker was set as a binding-in self-calibration to reduce errors from the angle and light dependency. The method realized the visual semi-quantitation referring to a standard card, as well as the ratio quantitation using the gray value output with LOD of 0.82 µmol L -1 . And the as-developed test strip was accessible, portable, and reliable, thus offering a platform for the rapid on-site detection of glyphosate and other residual pesticides., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

A colorimetric-electrochemical dual-mode analytical method based on bismuth metal-organic framework nanozyme was developed for label-free and trace/ultra-trace Cr 6+ detection. 3D ball-flower shaped bismuth oxide formate (BiOCOOH) was used as the precursor and template to facilely construct the metal-organic framework nanozyme BiO-BDC-NH 2 , which possesses intrinsic peroxidase-mimic activity to effectively catalyze the colorless 3,3',5,5'-tetramethylbenzidine into blue oxidation products in the presence of hydrogen peroxide. Based on Cr 6+ to promote the peroxide-mimic activity of BiO-BDC-NH 2 nanozyme, a colorimetric method for Cr 6+ detection was developed with the detection limit of 0.44 ng mL -1 . Cr 6+ can be electrochemically reduced to Cr 3+ that would specifically inhibit the peroxidase-mimic activity of BiO-BDC-NH 2 nanozyme. Thus, the colorimetric system for Cr 6+ detection was converted into a low-toxic and signal-off electrochemical sensor. The electrochemical model showed upgraded sensitivity and a lower detection limit of 9.00 pg mL -1 . The dual-model method was developed for selective appropriate sensing instruments in different detection scenarios, which can provide built-in correction for environmental effects, as well as the development and utilization of dual-signal sensing platforms for trace to ultra-trace Cr 6+ rapid assay., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Phthalate esters (PAEs) and bisphenol A (BPA) are endocrine-disrupting chemicals (EDCs), which are widely used in the production of food plastic packaging and easily migrate to food. Continuous exposure to EDCs may cause harm to human health. Herein, magnetic covalent organic framework TFP-NDA/Fe 3 O 4 was synthesized by magnetizing covalent organic framework TFP-NDA through a facile coprecipitation method, and used as an adsorbent for rapid solid-phase extraction of PAEs (diethyl phthalate (DEP), diisobutyl phthalate (DIBP) and dibutyl phthalate (DBP)) and BPA. The extraction equilibrium can be reached within 12 min. By combination with a gas chromatography-flame ionization detector, the limits of detection were 0.7-2.3 μg L -1 and the linear ranges were 10-500 μg L -1 for diethyl phthalate (DEP) and 10-1000 μg L -1 for diisobutyl phthalate (DIBP), dibutyl phthalate (DBP) and BPA with R 2 > 0.9916. In beverage samples (plastic bottled drinking water, juice and carbonated drink), the developed method was successfully applied to extract and quantify PAEs and BPA with recoveries ranging from 81.7% to 114.2%.

A portable device is conducive to the on-site detection of heavy metal ions at trace level in food and the prevention of related food safety issues. In this work, an electrochemical device stacked up with flat electrodes was developed for the detection of Pb 2+ and Cd 2+ . The top layer of the device is a carbon paper as working electrode, which is modified with amino functionalized cobalt-based metal-organic framework and gold nanoparticles. The bottom layer was constructed with the carbon counter electrode and Ag/AgCl reference electrode, and a punched sample cell (Φ = 8 mm) was in the middle. The proposed method could simultaneously determinate Pb 2+ and Cd 2+ via anodic stripping voltammetry with the detection limit of 7.0 × 10 -2 ng mL -1 and 1.1 × 10 -2 ng mL -1 , and was applied in real food samples (drinking water, juice, tea, grain, fruits, vegetables, liver and aquatic products) with the recovery of 91.2-105.4 % and 90.2-111.2 %, respectively., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Based on covalent organic framework (COF) 1,3,5-tris-(4-formylphenyl)benzene-benzidine (TFPB-BD) in situ grown on Fe 3 O 4 hollow microspheres and combined with gas chromatography-flame thermionic detector, a rapid and simple stir bar sorptive-dispersive microextraction method was developed for the determination of five triazole pesticides (paclobutrazol, hexaconazole, flusilazole, propiconazole, and tebuconazole). The synthesized TFPB-BD/Fe 3 O 4 microspheres were characterized by transmission electron microscope, vibrating sample magnetometer, and thermogravimetric analysis, which showed that the material has strong magnetism and higher load capacity of COF. Under optimal conditions, the extraction equilibrium could be achieved within 9 min with detection limits of 0.17-1.48 μg L -1 (S/N = 3) and a linear range of 5-1000 μg L -1 . The developed method was applied to the determination of trace triazole pesticides in apples, pears, and cabbages with recoveries from 81 to 117%., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Glyphosate, a broad-spectrum and high-efficiency herbicide, could accumulate in the human body through the consumption of agri-food products. Herein, a ratio fluorescence sensor based on rhodamine B-embedded amino-functionalized iron-based metal-organic framework (MOF, NH 2 -MIL-88(Fe)@RhB) bonded with Cu 2+ was developed for rapid detection of glyphosate. The synthesized NH 2 -MIL-88(Fe) was a biconical prism and had a cavity for the embedding of RhB as a reference compound. In the presence of Cu 2+ , Lewis interactions with NH 2 -MIL-88(Fe)@RhB cause the fluorescence signal to be turned off. When glyphosate was added, the signal was turned on due to chelation with Cu 2+ and hydrogen bonding interactions with NH 2 -MIL-88(Fe)@RhB. Under optimal conditions, the developed sensor exhibited a linear range of 0.60-45 μmol L -1 with a response time of less than 1 min. The sensor was applied in the analysis of agri-food products (tea, soybean, wheat, cucumber), with recoveries between 97.93% and 109.06%, indicating its promising application in agri-food safety., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Sulfonamides (SAs) were widespread in animal-derived food at trace level, which could trigger hazards to human health. Herein, electric field enhanced thin-film microextraction (EE-TFME) was developed based on carbon cloth (CC) modified with metal-organic frameworks (MOFs) for extraction of SAs (sulfadiazine, sulfathiazole, sulfamerazine, sulfadimidine, sulfamethoxazole and sulfisoxazole), which were a series of polar analytes. MIL-101(Cr) was in situ synthesized on CC via hydrothermal reaction and then was used as positive electrode in EE-TFME for adsorption of SAs. Compared with traditional TFME, EE-TFME shortened extraction equilibrium time from 30 min to 15 min. Coupled with high-performance liquid chromatography (HPLC), the limits of detection (LODs) were 2.5-4.5 µg/L, while the repeatability and intermediate precision was lower than 9.1%. Quantitative determination of SAs in extracts of animal-derived samples, such as honey, pork, chicken and milk, was achieved with recoveries from 81.7% to 114.2%. The developed MOF/CC-based EE-TFME has a great potential in rapid extraction of similar polar or ionic analytes from complex food matrices., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

A novel ratiometric electrochemical sensor was developed based on a carbon cloth electrodeposited with silver nanoparticles and drop-coated by covalent organic framework (COF-LZU1) for simultaneous determination of bisphenol A (BPA) and bisphenol S (BPS). Carbon cloth exhibited a significantly larger electrochemical active area than common glassy carbon electrodes (27.5 times). Silver nanoparticles not only provided a stable reference signal but also enhanced electroactivity for the oxidation of BPA and BPS. COF-LZU1 with good adsorption performance and large periodic π-arrays promoted the enrichment of BPA and BPS to further increase the current response. Compared with the traditional single-signal electrochemical sensor, the developed ratiometric sensor exhibited better reproducibility and a wider linear range for BPA and BPS from 0.5 to 100 μM with a limit of detection of 0.15 μM. Furthermore, the developed sensor showed excellent stability and superior anti-interference ability. The real sample analysis for BPA and BPS has been successfully carried out in mineral water, electrolyte drink, tea, juice, and beer with recoveries of 88.3-111.7%. The developed ratiometric sensor is expected to be a candidate for the preparation of other electrochemical sensors and the analysis of additional practical samples., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

The sensitivity and selectivity of electrochemical analysis are challenging due to the materials used for electrode modification as well as electrical conductivity, catalytic activity and recognition ability of the working electrode. In this work, a portable 3D-printed electrochemical electrode clamp was designed and applied in combination with the developed covalent organic framework (COF DQTP)-modified pencil graphite electrode (DQTP/PGE). The β-ketoenamine-linked COF DQTP synthesized by 1,3,5-triformylphloroglucinol (TP) and 2,6-diaminoanthraquinone (DQ) through solvothermal method is a porous crystalline with excellent conductivity and large periodic π-arrays, coupled with commercial available pencil graphite electrode to fabricate a disposable sensor for simultaneous determination of environmental endocrine disruptors bisphenol A and bisphenol S. The DQTP/PGE sensor exhibited high electrical conductivity and catalytic activity, and a good linearity was obtained in a range of 0.5-30 μM for two bisphenols with a detection limit of 0.15 μM (S/N = 3). Moreover, the sensor showed a reproducible and stable response over one month with negligible interference, and an accepted recovery with real food packaging samples., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Metal-organic frameworks (MOFs), a sort of dispersive solid-phase extraction (d-SPE) material, has shown considerable prospects in the pretreatment of food, biological and other complex samples. Herein, we developed a method for compounding MOFs for d-SPE and trace determination of tetracyclines (TCs) in honey. When the compounding ratio of MIL-101 (Cr), MIL-100 (Fe) and MIL-53 (Al) was 7:1:2, adsorption-extraction was effective. Followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), the limits of detection were 0.073-0.435 ng/g and the limits of quantitation ranged from 0.239 to 1.449 ng/g for oxytetracycline, tetracycline, chlortetracycline and doxycycline. The method was applied to four kinds of honey samples with recoveries from 88.1% to 126.2%. The compounding of MOFs provides a strategy for purification and multi-target extraction from complex food matrices by d-SPE., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this work, electro-enhanced solid-phase microextraction (EE-SPME) and covalent organic framework (COF) were adopted to improve the extraction efficiency. A conductive COF synthesized of 2,6-diaminoanthraquinone (DQ) and 1,3,5-triformylphloroglucinol (TP) was in situ bonded to the stainless steel wire via facile solution-phase approach and used as the EE-SPME fiber coating to preconcentrate a typical endocrine disruptor bisphenol A (BPA). Compared with conventional SPME, the DQTP bonded fiber coupled with EE-SPME device exhibited higher extraction efficiency and achieved extraction equilibrium within 10 min. The proposed approach based on EE-SPME and gas chromatography coupled with flame ionization detector gave a linear range of 0.05-10 μg mL -1 and detection limit of 3 μg L -1  (S/N = 3) with good precision (<6.7%) and reproducibility (<7.1%) spiked with 0.1, 0.5, 1.0 μg mL -1 BPA. Quantitative determination of BPA in extracts of food packagings (mineral water bottles, milk boxes and milk tea cups) was achieved with recoveries from 88.6 to 118.0%., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Phthalate esters (PAEs), a category of widely used plasticizers, are tend to migrate from plastic packaging to drinks. In this paper, we develop a simple and rapid coprecipitation method for synthesis of a magnetic covalent organic framework (COF) adsorbent. The fabricated COF-(TpBD)/Fe 3 O 4 was applied to magnetic solid phase extraction (MSPE) of 15 phthalate esters (PAEs) for subsequent GC-MS/MS determination in beverage samples. The as-synthesized magnetic adsorbent exhibited great potential in PAEs analysis with a limit of detection of 15 PAEs ranged from 0.005 to 2.748 μg L -1  (S/N = 3). The intra-day and inter-day relative standard deviations (RSD) value of the PAEs were less than 8.8% and 9.9%, respectively. The adsorbent can be reused after washing with methanol. The developed method was successfully applied for the determination of trace PAEs in eight beverages with recoveries ranging from 79.3% to 121.8% and RSDs were less than 11.9%. This work provides a simple magnetization process, which facilitates the application of COFs for enrichment and separation of PAEs in beverages with different matrices., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Covalent organic framework TpBD was grafted on stainless steel wire with polydopamine as a linker. The fabricated TpBD bonded stainless steel wire was used as the solid-phase microextraction fiber to extract sixteen polycyclic aromatic hydrocarbons (PAHs) for subsequent GC-MS/MS determination in grilled meat samples. The developed method gave the limits of detection (S/N = 3) from 0.02 (pyrene)-1.66 (naphthalene) ng L -1 and enhancement factors from 1069 (naphthalene)-10879 (benz(a)anthracene). The relative standard deviations (RSDs) for intra-day and inter-day study are in the range of 2.6%-8.5% and 4.5%-9.4%, respectively. The fiber-to-fiber RSDs for three parallel prepared fibers were 5.3%-10.0%. One TpBD bonded fiber can stand at least 200 cycles without significant loss of extraction efficiency. The developed method was successfully applied for the determination of trace PAHs in grilled meat samples with recoveries from 85.1% to 102.8%., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The widespread use of antibiotics leads to spread of resistance bacteria and genes in natural water and has a potential threat to human health. Herein, a nanorod CoNiFe-MOF/LDH was synthesized using a self-sacrificial strategy and employed to degrade sulfamethazine (SMT) by heterogeneous electro-Fenton (HEF). The conversion of CoNiFe-LDH to CoNiFe-MOF/LDH resulted in a significant enhancement of specific surface area (from 13.96 to 32.26 m2 g−1) and electroactive surface area (from 2.20 to 4.22 mm2), and the degradation rate of SMT increased from 88.53% to 98.41% within 60 min. The free radical capture experiments indicated that ·OH and 1O 2 played a significant role in the HEF process. The CoNiFe-MOF/LDH catalyst could be recycled 5 times with degradation rate of over 90%, it also demonstrated excellent resistance towards inorganic ions and humic acid. In addition, the CoNiFe-MOF/LDH exhibited remarkable degradation efficiency for 8 sulfonamides (over 89%). Mass spectrometry analysis indicated that SMT was oxidatively degraded via three possible pathways. According to the analysis of Toxicity Estimation Software Tool, the acute toxicity of SMT was effectively weakened. The CoNiFe-MOF/LDH catalyst has potential application prospect in wastewater treatment. [Display omitted] • A CoNiFe-MOF/LDH was synthesized for sulfamethazine degradation by the HEF process. • The electrocatalytic performance of CoNiFe-MOF/LDH was greatly improved. • The CoNiFe-MOF/LDH catalyst displayed favorable stability and resistance. • Sulfamethazine was efficiently degraded and toxicity of its products was weakened. [ABSTRACT FROM AUTHOR]

We report herein seven novel lanthanide metal–organic frameworks (Ln-MOFs), [M(L27)(DMA)(H2O)·XH2O]n (TCZ-M), (M = Nd, Sm, Eu, Gd, Tb, Dy, Ho), (X = 2 or 3) (H3L27 = 2,7-bis(4-benzoic acid)-N-(4-benzoic acid)carbazole, DMA = N,N-dimethylacetamide, TCZ = “T”-shape carbazole-based MOFs, L27 = fully deprotonated H3L273− ligand). X-ray crystallography showed that all the TCZ-M (M = Nd, Sm, Eu, Gd, Tb, Dy, Ho) are isomorphous and possess a 3,6-connected three-dimensional (3D) framework with a point symbol of {4·62}2{42·610·83}. The photoluminescence measurement indicates that TCZ-Eu shows reddish-orange emission bands and TCZ-Sm shows both visible and near-infrared (NIR) emission bands. Magnetic susceptibility measurements show deviations from the Curie law mainly owing to the split of the ground term due to the ligand field and spin–orbit coupling in TCZ-Eu and TCZ-Sm. The magnetic properties of TCZ-M (M = Nd, Gd, Tb, Dy, Ho) are also investigated, and the results indicate a ferromagnetic interaction between the Tb3+ magnetic centers in TCZ-Tb and the antiferromagnetic interactions in TCZ-M (M = Nd, Gd, Dy, Ho). [ABSTRACT FROM AUTHOR]

Glyphosate, a potent herbicide wildly used in the world, involves potential hazards to human health by accumulating in the food chain. Due to its absence of chromophores and fluorophores, the rapid visual detection of glyphosate has always been difficult. Herein, a paper-based geometric field amplification device visualized by the amino-functionalized bismuth-based metal-organic framework (NH 2 –Bi-MOF) was constructed for sensitive fluorescence determination of glyphosate. Fluorescence of the synthesized NH 2 –Bi-MOF was immediately enhanced by interaction with glyphosate. The field amplification of glyphosate was implemented by coordinating the electric field and the electroosmotic flow, which was orchestrated by the geometric configuration of paper channel and the concentration of polyvinyl pyrrolidone, respectively. Under the optimal conditions, the developed method exhibited a linear range of 0.80–200 μmol L−1 with about 12500-fold signal enhancement achieved by just 100 s electric field amplification. It was applied to soil and water with recoveries between 95.7% and 105.6%, holding great prospects in on-site analysis of hazardous anions for environment safety. [Display omitted] • A fluorescent amino-functionalized bismuth-based MOF was prepared. • An electro-field amplification method was constructed for anions. • Simultaneous field amplification and fluorescence determination of glyphosate. • The method was applied to soil and water samples. [ABSTRACT FROM AUTHOR]

Glyphosate (GLY), an exceedingly effective herbicide, has raised worries about the risks posing to the ecosystem and human health due to excessive exposure. An electrochemical sensor based on copper porphyrin metal organic framework and gold nanoparticles modified carbon paper (Cu-TCPP/AuNPs/CP) was developed for sensitive determination of GLY by differential pulse voltammetry (DPV). The Cu-TCPP has large surface area and excellent catalytic activity, increasing the copper sites to combine with GLY for selective determination and improving the sensitivity of the electrochemical sensor. Under optimized conditions, the constructed sensor has a linear range from 0.2 to 120 μ mol L−1 with a detection limit of 0.03 μ mol L−1 (S/N = 3). The sensor was applied to water, soybean, wheat and carrot with the recovery ranging from 97.5% to 110.7%. After two weeks storage at 4 °C, the peak current of the sensor remains 86.6% of the original value with negligible interference. This sensor has a great potential application in water, soil and other environmental samples. • Copper porphyrin MOFs provides reaction sites for selective detection of glyphosate. • A synergistic effect between MOFs and gold nanoparticles increases conductivity. • Carbon paper provides a prospective sensing platform than traditional electrodes. • A sensitive electrochemical sensing method for glyphosate. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of a neutral rigid tripodal ligand, 1,3,5-tris(1-imidazolyl)benzene (tib), with Zn(NO3)2·6H2O and Zn(ClO4)2·6H2O produced two metal–organic frameworks, [Zn3(tib)4·6NO3·6H2O·3DMA]n (1) and [Zn2(tib)3·4ClO4·6H2O·6DMA]n (2) (DMA = N,N-dimethylacetamide), respectively, which feature different cage-to-cage connections. Both compounds 1 and 2 exhibit 3D cationic frameworks with charge-balancing extraframework anions. Interestingly, the counterions NO3− and ClO4− play an important role in the fabrication of structures of 1 and 2. Compound 1 shows 2-fold interpenetration while 2 gives a non-interpenetrated 3D porous framework. Adjacent M6L4 octahedral cages in compound 1 are further linked via vertex sharing to construct a 3D framework. For compound 2, neighboring octahedral cages connect with each other through sharing four metal ions which are in the equatorial plane to generate a 2D layer. Furthermore, the 2D layers are linked by other layers via sharing the other two metal ions which are in the axial position, finally forming a 3D supramolecular framework. The photoluminescence of compounds 1 and 2 has been investigated in the solid state. Gas sorption measurements were conducted on the activated 1, showing a H2 uptake of 1.2 wt% at 77 K and 1 bar with high initial adsorption enthalpy of 8.4 kJ mol−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple prepared Ce-MOF@PANI exhibited excellent electrocatalytic activity. • The doping of PANI to Ce-MOF enhanced the conductivity. • A sensitive electrochemical sensor was developed for determining carbendazim. Carbendazim (CBZ) has generated significant attention due to potential harm to human health, thus developing a simple and economy-friendly approach for determining CBZ is vital. Herein, Cerium metal-organic framework (Ce-MOF) and polyaniline (PANI) were composited under mild condition and modified on carbon cloth (CC) to fabricate an electrochemical sensor based on Ce-MOF@PANI/CC for fast and sensitive determination of CBZ. Rod-shaped Ce-MOF facilitated the dispersion of PANI, while the doping of PANI improved conductivity of Ce-MOF to amplify detection signal. Moreover, the modification of Ce-MOF@PANI on CC increased the electrochemical active area of CC by 2.78 times. Under optimized conditions, the method demonstrated a linear range of 0.1–80 μM and a detection limit of 12.6 nM. Additionally, the response value of the sensor to CBZ still maintained 94.32% of the initial value after 15 days. It also had good reproducibility and anti-interference. The sensor was utilized for detecting CBZ in fruit (apple, pear), vegetables (tomato, cucumber), and water (lake, tap water) with recovery of 92.31%–105.47% consistent with those of high-performance liquid chromatography. [ABSTRACT FROM AUTHOR]