Constructing perfluorinated UiO-67 for enrichment of polycyclic aromatic hydrocarbons in seawater and seabed sediments.

To investigate the ocean contamination caused by polycyclic aromatic hydrocarbons (PAHs), UiO-67/perfluorooctanoic acid (UiO-67/PFOA) was synthesized through solvent-assisted ligand incorporation method. The UiO-67/PFOA was then served as an adsorbent in headspace solid-phase microextraction (HS-SPME) technology for collecting and concentrating trace PAHs. The addition of the PFOA improved the hydrophobicity and stability of the UiO-67/PFOA coating, and the C-F functional group in UiO-67/PFOA could form the pseudo hydrogen bonding with the CH on the benzene ring of PAHs, which endowed the UiO-67/PFOA with 1.

Boronic acid functionalized of covalent organic framework for high performance capture of trace phthalates.

In order to improve the enrichment performance of parent covalent organic frameworks (COFs), boronic acid functionalized of COF (COF-B(OH)) was obtained by a simple standing method for the first time. The obtained COF-B(OH) exhibited the new characteristics that were not possessed by pure COF and was employed as the solid phase microextraction (SPME) coating material for highly efficient enrichment of trace endocrine disruptors phthalates (PAEs). Compared to pure COF, the synergistic effect of the newly emerged unique pore structure and boric acid interaction sites, and the large specific surface area and the abundant benzene ring structure inherited by original COF framework endowed COF-B(OH) with enhanced enrichment performance for PAEs.

MOF-derived porous carbon microspheres Ni@C-acid as solid-phase microextraction coating for extraction of polycyclic aromatic hydrocarbons from tea infusions.

The improvement of the stability and adsorption properties of materials on targets in sample pre-treatment has long been an objective. Extensive efforts have been made to achieve this goal. In this work, metal-organic framework Ni-MOF precursors were first synthesized by solvothermal method using polyvinylpyrrolidone (PVP) as an ideal templating agent, stabiliser and nanoparticle dispersant.

Dose-Dependent Effect on Plant Growth of Exposure to Metal-Organic Framework MIL-101(Cr).

With the increasing use of metal-organic frameworks (MOFs), they will inevitably enter the environment intentionally or unintentionally. However, the effects of MOFs on plant growth are poorly understood. Here, we investigated the effects of exposure of the rhizosphere to MOFs on plant growth.

Probing the stability of metal-organic frameworks by structure-responsive mass spectrometry imaging.

The widespread application of metal-organic frameworks (MOFs) is seriously hindered by their structural instability and it is still very challenging to probe the stability of MOFs during application by current techniques. Here, we report a novel structure-responsive mass spectrometry (SRMS) imaging technique to probe the stability of MOFs. We discovered that intact CuBTC (as a model of MOFs) could generate the characteristic peaks of organic ligands and carbon cluster anions in laser desorption/ionization mass spectrometry, but these peaks were significantly changed when the structure of CuBTC was dissociated, thus enabling a label-free probing of the stability.

[Application progress of covalent organic framework materials in extraction of toxic and harmful substances].

Toxic and hazardous substances constitute a category of compounds that are potentially hazardous to humans, other organisms, and the environment. These substances include pesticides (benzoylureas, pyrethroids, neonicotinoids), persistent organic pollutants (polycyclic aromatic hydrocarbons, polychlorinated biphenyls, perfluorinated compounds), plasticizers (phthalate esters, phenolic endocrine disruptors), medicines (sulfonamides, non-steroid anti-inflammatory drugs, tetracyclines, fluoroquinone antibiotics), heterocyclic aromatic amines, algal toxins, and radioactive substances. Discharge of these toxic and harmful substances, as well as their possible persistence and bioaccumulation, pose a major risk to human health, often to the extent of being life-threatening.

Rapidly covalent immobilization of β-ketoenamine-linked covalent organic framework on fibers for efficient solid-phase microextraction of phthalic acid esters.

Rapid and convenient preparation of covalent organic framework (COF) coated fibers is of great significance to solid-phase microextraction (SPME) technology. In this work, a novel chemical preparation strategy was established for rapid fabrication of β-ketoenamine-linked COF coatings, in which clay-like starting materials of COFs were first wrapped on the fiber surface through self-viscosity and further fixed on the fiber in an oven via chemical bonding. Based on this strategy, four different COF (TpTph, TpPa-1, TpBD and TpTpb) coated fibers was fabricated within 1 h, which is very rapid compared to the recently reported research.

Controllable Synthesis of Hollow Microtubular Covalent Organic Frameworks as an Enzyme-Immobilized Platform for Enhancing Catalytic Activity.

Despite great achievement that has been made in the synthesis of covalent organic frameworks (COFs), precise construction of COFs with well-defined nano/microstructures poses a rigorous challenge. Herein, we introduce a simple template-free strategy for controllable synthesis of hollow microtubular COFs. The obtained COFs show a spontaneous morphology transformation from a microfiber to a hollow microtubular structure when the concentrations of catalytic acid are regulated elaborately.

Nanoscale Covalent Organic Frameworks with Donor-Acceptor Structures as Highly Efficient Light-Responsive Oxidase-like Mimics for Colorimetric Detection of Glutathione.

Although organic artificial enzymes have been reported as biomimetic oxidation catalysts and are widely used for colorimetric biosensors, developing organic artificial enzymes with high enzymatic activity is still a challenge. Two-dimensional (2D) covalent organic frameworks (COFs) have shown superior potential in biocatalysts because of their periodic π-π arrays, tunable pore size and structure, large surface area, and thermal stability. The interconnection of electron acceptor and donor building blocks in the 2D conjugated COF skeleton can lead to narrower band gaps and efficient charge separation and transportation and thus is helpful to improve catalytic activity.

In situ room-temperature rapidly fabricated imine-linked covalent organic framework coated fibers for efficient solid-phase microextraction of pyrethroids.

A facile and rapid strategy for preparation of covalent organic framework (COF) coated fibers at ambient temperature is urgently needed for solid-phase microextraction (SPME) technology. In this work, an in situ room-temperature rapid growth strategy was developed to high-efficiently fabricate imine-linked COF (TPB-DVA) coated fibers in as little as 30 min at room temperature, and the thickness of the coating reached 9 μm. The prepared TPB-DVA coated fiber offer high thermal and chemical stability, and outstanding service lifetime.

Facile synthesis of spherical covalent organic frameworks as stationary phases for short-column liquid chromatography.

Micron-sized spherical covalent organic frameworks (SCOFs) with tunable sizes, narrow size distribution, and significant mono-dispersity were simply synthesized at room temperature. Thanks to their high specific surface areas, high chemical and mechanical stability, the SCOFs were used for the first time as stationary phases for high-efficiency separation of various small molecules and protein digests via short-column liquid chromatography.

Room-temperature controllable synthesis of hierarchically flower-like hollow covalent organic frameworks for brain natriuretic peptide enrichment.

A facile strategy was introduced for room-temperature controllable synthesis of hierarchically flower-like hollow COFs (FHF-COFs). Furthermore, the universality for synthesis of the HFH-COFs was validated by altering the building units. Inspired by the unique morphology, extremely large surface area and good chemical stability, HFH-COFs could serve as an attractive adsorption probe by loading with gold nanoparticles and be applied to enrichment of brain natriuretic peptide from human serum.

Thiol functionalized covalent organic framework for highly selective enrichment and detection of mercury by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

A spherical thiol-functionalized covalent organic framework (COF-SH) was designed via a facile thiol-yne click reaction of a alkynyl-terminated COF and pentaerythritol tetra(3-mercaptopropionate). The COF-SH was explored as a new adsorbent for the selective enrichment of Hg2+. The as-prepared COF-SH exhibited a uniform mesoporous structure, a high abundance of binding sites, and good chemical stability, which endow it with great performance for the adsorption of Hg2+ and its corresponding maximum adsorption capacity was up to 617.

One-pot room-temperature synthesis of covalent organic framework-coated superhydrophobic sponges for highly efficient oil-water separation.

Frequent oil-spill accidents not only cause serious and long-term damage to marine ecosystems, but also lead to a huge loss of valuable natural resources. To lighten the environmental pollution of oil spills as quickly as possible, an efficient and environment-friendly approach for oil-water separation is highly desirable. Herein, a facile one-pot room-temperature approach was developed for large-scale fabrication of covalent organic framework-coated superhydrophobic sponges (sponges@COFs).

Facile fabrication of magnetic covalent organic frameworks and their application in selective enrichment of polychlorinated naphthalenes from fine particulate matter.

Magnetic covalent organic frameworks (FeO@TPPCl) were synthesized via a one-pot process in which magnetic nanoparticles (FeO@MNP) served as a magnetic core and 2,4,6-trihydroxy-1,3,5-benzenetricarbaldehyde (TP) and 2,2',5,5'-tetrachlorobenzidine (PCl) as two building blocks to form a shell. The as-prepared FeO@TPPCl nanoparticles have superior features, including large surface area (186.5 m g), high porosity, strong magnetic responsiveness (42.

Facile synthesis of tubular magnetic fluorinated covalent organic frameworks for efficient enrichment of ultratrace polybrominated diphenyl ethers from environmental samples.

Polybrominated diphenyl ethers (PBDEs), known as the most widely used brominated flame retardant, have received great public concern due to its hidden environment and health problems. Development of highly selective and sensitive analytical approaches for enrichment and detection of ultratrace PBDEs are in high demand. Conventional sample pretreatment techniques usually require tedious procedures, long time, and excessive consumption of solvent and sample, thus hindering ultrasensitive detection of PBDEs.

High-throughput screening of bisphenols using magnetic covalent organic frameworks as a SELDI-TOF-MS probe.

Core-shell structured magnetic covalent organic framework (FeO@COF) nanospheres were rapidly synthesized at room temperature using the monodisperse FeO nanoparticles (NPs) as magnetic core and benzene-1,3,5-tricarbaldehyde (BTA) and 3,3'-dihydroxybenzidine (DHBD) as two building blocks (denoted as FeO@BTA-DHBD), respectively. They can serve as a mass spectrometry probe for rapid and high-throughput screening of bisphenols (BPs) from pharmaceuticals and personal care products (PPCPs) by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). The FeO@BTA-DHBD nanospheres showed some superior features involving average pore size distribution (2.

A spherical covalent-organic framework for enhancing laser desorption/ionization mass spectrometry for small molecule detection.

A spherical vinyl-functionalized covalent-organic framework (COF-V) was prepared at room temperature by a facile method and applied as a novel substrate for surface-enhanced laser desorption/ionization mass spectrometry (SELDI-MS). Compared with conventional organic matrices, the spherical COF-V with high crystallinity and good monodispersity exhibited high sensitivity, no matrix background interference, wide-range applicability, high salt tolerance and reproducibility in the characterization of small molecules. Considering these advantages, the applicability of the spherical COF-V-based SELDI-MS method was successfully demonstrated by determining trace amounts of glucose in diabetic urine, which would be a promising candidate for clinical diagnosis of diabetes.

TiO nanoparticles accelerate methanogenesis in mangrove wetlands sediment.

In this study, the response of methane (CH) production to the addition of titanium dioxide nanoparticles (TiO NPs) with three types of short-chain fatty acids (sodium acetate, sodium propionate and sodium butyrate) as carbon sources in mangrove sediment was investigated. The results showed that the maximum CH formation rate increased by 45.2%, 32.

Size-Controllable Synthesis of Uniform Spherical Covalent Organic Frameworks at Room Temperature for Highly Efficient and Selective Enrichment of Hydrophobic Peptides.

Covalent organic frameworks (COFs) represent a new class of porous crystalline polymers with a diversity of applications. However, synthesis of uniform spherical COFs poses a great challenge. Here, we present size-controllable synthesis of uniform spherical COFs from nanometer to micrometer scale by a facile approach at room temperature.

Coordination mode engineering in stacked-nanosheet metal-organic frameworks to enhance catalytic reactivity and structural robustness.

Optimising the supported modes of atom or ion dispersal onto substrates, to synchronously integrate high reactivity and robust stability in catalytic conversion, is an important yet challenging area of research. Here, theoretical calculations first show that three-coordinated copper (Cu) sites have higher activity than four-, two- and one-coordinated sites. A site-selective etching method is then introduced to prepare a stacked-nanosheet metal-organic framework (MOF, CASFZU-1)-based catalyst with precisely controlled coordination number sites on its surface.

Postsynthetic Functionalization of Zr-Immobilized Core-Shell Structured Magnetic Covalent Organic Frameworks for Selective Enrichment of Phosphopeptides.

Chemical modification of covalent organic frameworks (COFs) is indispensable for integrating functionalities of greater complexity and accessing advanced COF materials suitable for more potential applications. Reported here is a novel strategy for fabricating controllable core-shell structured Zr-immobilized magnetic COFs (MCNC@COF@Zr) composed of a high-magnetic-response magnetic colloid nanocrystal cluster (MCNC) core, Zr ion-functionalized two-dimensional COFs as the shell by sequential postsynthetic functionalization and, for the first time, the application of the MCNC@COF@Zr composites for efficient and selective enrichment of phosphopeptides. The as-prepared MCNC@COF@Zr composites possess regular porosity with large surface areas, high Zr loading amount, strong magnetic responsiveness, and good thermal/chemical stability, which can serve as an ideal adsorbent for selective enrichment of phosphopeptides and simultaneous size exclusion of biomacromolecules, such as proteins.

Recent advances in biomolecule immobilization based on self-assembly: organic-inorganic hybrid nanoflowers and metal-organic frameworks as novel substrates.

In the past few years, the immobilization of biomolecules on hybrid nanoflowers and metal-organic frameworks (MOFs) via self-assembly synthesis has received much attention due to its simplicity, high efficiency, and a bright prospect of enhancing the stability, activity and even selectivity of biomolecules compared to conventional immobilization methods. In the synthesis of organic-inorganic hybrid nanoflowers, biomolecules used as organic components are simply mixed with metal ions which act as inorganic components to form flower-like nanocomposites, while in the self-assembly process of encapsulating biomolecules in MOFs (biomolecule@MOF composites), the biomolecules just need to be added to the precursor mixtures of MOFs, in which the biomolecules are therefore embedded in MOF crystals with small pores. In this review, we focus on the recent advances of these composites, especially in the synthesis strategies, mechanism and applications in biosensors, biomedicine, pollutant disposal, and industrial biocatalysis, and future perspectives are discussed as well.