Natural and synthetic zeolites are important microporous materials. [ 1 ] The highly ordered structures and tunable compositions of aluminosilicate frameworks are responsible for their extraordinary performances. After the discovery of zeolitic metal imidazolate frameworks, ranging from zeolite-like cobalt imidazolates [ 2 ] to the SOD-, ANA-, and RHO-type (three-letter codes of zeolite topologies) zinc benziimidazolate [ 3 ] and 2-alkylimidazolates, [ 4 ] these novel porous coordination polymers (PCPs) have blossomed in the past few years. [ 5 ] The similarity of the bended exo-bidentate coordination mode of imidazolate with that of the O atom in aluminosilicates has been considered as a determinative construction principle ( Figure 1 ). The rich structure-directing role of imidazolate side groups provides an additional variable for enumeration of new zeolitic structures. [3][4][5] Nevertheless, there seems to be some inherent difference between the inorganic and metal-organic counterparts. For example, inorganic zeolites are negatively charged aluminosilicate frameworks and their pore surface property can be routinely tailored by adjusting the Al/Si ratio and/or cation exchange. In contrast, PCPs (including metal-organic zeolites) are well-known to be completely ordered materials.Among the large family of known metal-organic zeolites, SOD-[Zn(mim) 2 ] (Hmim = 2-methylimidazole [ 4 ] ) is noteworthy for its high porosity and exceptional stability. The synthesis, porous property, sorption mechanism, and application of MAF-4 (the metal azolate framework 4) have attracted much attention. [ 6 ] However, MAF-4 only adsorbs many important gases, such as H 2 , CO 2 , and C 2 H 2 weakly, due to the lack of a strong adsorption site on its pore surface. While new functionalities of MAF-4 are still emerging, efforts have been devoted to the structural modifi cation of this prototype framework. Because imidazolates are almost the shortest linkers in PCPs, variation of the metal ion and/or substituent groups on the imidazolate linker can largely alter porosity (size or volume), change the framework, [ 5e-h ] and even alter the whole network topology. Metal ion substitution can effectively change the pore surface properties of PCPs functionalized with coordinatively unsaturated metal centers. [ 7 ] However, the tetrahedral metal centers are shielded by the surrounding imidazolates in zeolitic frameworks and hence not effective for sorption. So far, tuning the sorption property of PCP by simple pore surface engineering instead of other porous parameters has rarely been reported. [ 7,8 ] Here, we report a straightforward approach for pore surface tailoring of the MAF-4 structure, which leads to not only drastic enhancement but also fi ne-tuning of the sorption performance for practical adsorptive applications. In principle, replacing a C-H moiety in MAF-4 with an isoelectronic N atom can provide a Lewis base active site for guest binding. [ 9 ] While the N atoms prefer coordination to metal ions during self-assembly, we show t...

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Light material: By virtue of the unique framework structure and very high oxygen permeability, a noble‐metal‐free, highly fluorescent, porous coordination polymer demonstrates a rapid, reversible, efficient, stable, and selective fluorescence‐quenching response toward oxygen.

Fucoidan is a kind of the polysaccharide, which comes from brown algae and comprises of sulfated fucose residues. It has shown a large range of biological activities in basic researches, including many elements like anti-inflammatory, anti-cancer, anti-viral, anti-oxidation, anticoagulant, antithrombotic, anti-angiogenic and anti-Helicobacter pylori, etc. Cancer is a multifactorial disease of multiple causes. Most of the current chemotherapy drugs for cancer therapy are projected to eliminate the ordinary deregulation mechanisms in cancer cells. Plenty of wholesome tissues, however, are also influenced by these chemical cytotoxic effects. Existing researches have demonstrated that fucoidan can directly exert the anti-cancer actions through cell cycle arrest, induction of apoptosis, etc., and can also indirectly kill cancer cells by activating natural killer cells, macrophages, etc. Fucoidan is used as a new anti-tumor drug or as an adjuvant in combination with an anti-tumor drug because of its high biological activity, wide source, low resistance to drug resistance and low side effects. This paper reviews the mechanism by which fucoidan can eliminate tumor cells, delay tumor growth and synergize with anticancer chemotherapy drugs in vitro, in vivo and in clinical trials.

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Phosphorescent complexes of precious metal ions are widely studied as optical sensing materials for molecular oxygen. Combining the advantages of luminescent complexes and porous matrixes, porous coordination polymers show great potential for oxygen‐sensing, although their sensitivity, requirement of precious metal, and device fabrication remain challenging issues. In this work, the photoluminescence and oxygen‐sensing properties of the porous Cu(I) triazolate framework [Cu(detz)] (MAF‐2, Hdetz = 3,5‐diethyl‐1,2,4‐trizole) is studied in detail, which shows high chemical stability in moisture and water, very long phosphorescent lifetime (116 μs) and large Stokes shift (14 562 cm−1), as well as considerable oxygen permeability (1.7 × 10−11 mol cm−1 s−1 bar−1) at ambient conditions, giving rise to exceptionally high luminescence quenching efficiency of 99.7% at 1 bar O2 (I 0/I 100 = 356) with a perfectly linear Stern‐Volmer plot (K SV = 356 bar−1, R 2 = 0.9998), fast response and good reversibility. Further, a counter‐diffusion crystal‐growth method was developed to fabricate MAF‐2 thin films protected by silicone rubbers as the first example of soft membrane oxygen sensor based on coordination polymer or metal‐organic framework, which exhibited extraordinary oxygen‐sensing performance (limit of detection = 0.047 mbar) and outstanding mechanical property, as well as outstanding chemical stability even in an acidic atmosphere.

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Flame-retardant (FR) additives are commonly used to improve the fire safety of synthetic polymers, which are widely employed in manufactured consumer goods. Incorporation of an FR in a polymer typically leads to deterioration of its mechanical properties. It also manifests itself in non-negligible volatile organic compound (VOC) release, which in turn increases environmental risks carried by both the application and disposal of the corresponding consumer goods. Herein, we present a hierarchical strategy for the design of composite materials, which ensures simultaneous improvement of both mechanical and fire-safety properties of polymers while limiting the VOC release. Our strategy employs porous metal−organic framework (MOF) particles to provide a multifunctional interface between the FR molecules and the polymer. Specifically, we demonstrate that the particles of environmentally friendly HKUST-1 MOF can be infused by a modern FRdimethyl methylphosphonate (DMMP)and then embedded into widely used unsaturated polyesters. The DMMP−HKUST-1 additive endows the resulting composite material with improved processability, flame retardancy, and mechanical properties. Single-crystal X-ray diffraction, thermogravimetric analysis, and computational modeling of the additive suggest the complete pore filling of HKUST-1 with DMMP molecules being bound to the open metal sites of the MOF.