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To overcome the poor conductivities and promote the application in the biosensors of metal-organic frameworks (MOFs), a simple approach was employed to improve their overall conductivity by adjusting the metal centers of MOFs and coating conductive polypyrrole (PPy) in the work. An unprecedented molybdenum oxide-based three-dimensional MOFs with helical channels (CuTRZMoO 4 ) was synthesized based on MoO 4 - , Cu 2+ ions and 1,2,3-trz for the first time, then combined with PPy to fabricate hybrid composites (CuTRZMoO 4 @PPy-n) with both advantages. The CuTRZMoO 4 modified glassy carbon electrode show high sensitivity for detecting the neurotransmitter dopamine (DA), and the CuTRZMoO 4 @PPy-2 modified glassy carbon electrode has the highest catalytical activity to DA with the linear detection range from 1 μM to 100 μM and the detection limit of 80 nM (S/N = 3) by differential pulse voltammetry (DPV). Moreover, the developed biosensor has good selectivity, reproducibility and stability. The concept behinds the new architecture to modify electrodes should promote the further development of MOF-based biosensors., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The preparation method and calcination temperature of metal-organic framework (MOFs)-derived materials are critical factors affecting catalytic performance. In this work, the preparation conditions of MOFS precursors were optimized, and zinc-based catalysts with different activities (MOF5-700, MOF5-750, and MOF5-800) were obtained by pyrolysis of MOFS precursors under nitrogen, which were then applied to an acetylene acetoxylation reaction system. According to the results, the conversion rate of acetic acid under catalysis was significantly different. (MOF5-700 (48%), MOF5-750 (62%), and MOF5-800 (22%)). Comparing the activity of the catalyst with the industrial catalyst Zn(OAc)2/AC (20%), MOF5-750 showed higher activity, and the acetic acid conversion rate remained around 60% after 50 h of stability testing. By characterization analysis, MOFs-derived materials were obtained after proper temperature pyrolysis. They have high mesoporous content, defects, and oxygen-containing functional groups and can maintain a good crystal structure, greatly reducing the loss of active components. This is the main reason for the good performance of the MOF5-750 catalyst in acetylene acetoxylation. Thus, the preparation conditions and favorable pyrolysis temperature of MOF derivative catalysts play a key role in the catalytic performance of acetylene acetoxylation. [ABSTRACT FROM AUTHOR]

To explore a novel colorimetric biosensor with high sensibility and selectivity, a new Wells–Dawson-type polyoxometalate (POM)-based metal–organic framework (MOF) with an eightfold helix, [Cu9(FKZ)12(H2O)8][H3P2W18O62]2·4H2O (CuFKZP2W18) (HFKZ = 1-(2,4-difluorophenyl)-1,1-bis[(1H-1,2,4-triazol-1-yl)methyl] ethanol), was successfully synthesized; then, polypyrrole (PPy) was introduced to fabricate CuFKZP2W18/PPy(n) nanocomposites (n = 7%, 15%, 30%) via a facile in situ oxidation polymerization process. All the results indicate that CuFKZP2W18/PPy(15%) as a colorimetric biosensor exhibits lower limits of detection (0.07 μM towards H2O2 and 0.627 μM towards ascorbic acid), smaller Km values (0.106 mM for H2O2 and 0.042 mM for o-phenylenediamine) and higher sensitivity (0.0227 1 μM−1 towards H2O2 and 0.0025 1 μM−1 to ascorbic acid) than most reported enzyme mimetics to the best of our knowledge. [ABSTRACT FROM AUTHOR]

The first polyoxometalate (POM)-containing nanocage based metal–organic framework (Zn-POMCF) was synthesized by a surfactant-assisted method. In contrast to the Zn-based metal–organic framework (Zn-MOF), the cooperative assembly of POM and a Zn/trz macrocycle gave rise to high stability and good electrochemical ability of the Zn-POMCF in lithium-ion batteries (LIBs). [ABSTRACT FROM AUTHOR]

Among various novel antimicrobial therapies, sonodynamic therapy (SDT) exhibits its advantages for the treatment of bacterial infections due to its high penetration depth and low side effects. In this study, a new nanosonosensitizer (HFH@ZIF-8) that loads sonosensitizer hematoporphyrin monomethyl ether (HMME) into zeolitic imidazolate framework-8 (ZIF-8), was constructed for killing multidrug-resistant (MDR) bacteria and treatment of in vivo infection diseases by SDT. In particular, the developed HFH@ZIF-8 exhibited enhanced water-solubility, good biocompatibility, and improved disease-targeting capability for delivering and releasing HMME and ablating the infected lesion. More importantly, the presence of oxygen-carrying hemoglobin for HFH@ZIF-8 can offer sufficient oxygen consumption by SDT, augmenting the efficacy of SDT by improving ROS generating efficiency against deep tissue multidrug-resistant bacterial infection. Therefore, this study paves a new avenue for treating infection disease, particularly for antibiotic resistant bacterial infection. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs)-derived materials with a large specific surface area and rich pore structures are favorable for catalytic performance. In this work, MOFs are successfully prepared. Through pyrolysis of MOFs under nitrogen gas, zinc-based catalysts with different active sites for acetylene acetoxylation are obtained. The influence of the oxygen atom, nitrogen atom, and coexistence of oxygen and nitrogen atoms on the structure and catalytic performance of MOFs-derived catalysts was investigated. According to the results, the catalysts with different catalytic activity are Zn-O-C (33%), Zn-O/N-C (27%), and Zn-N-C (12%). From the measurements of X-ray photoelectron spectroscopy (XPS), it can be confirmed that the formation of different active sites affects the electron cloud density of zinc. The electron cloud density of zinc affects the ability to attract CH3COOH, which makes catalysts different in terms of catalytic activity. [ABSTRACT FROM AUTHOR]