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Chikungunya virus, a mosquito-borne virus that causes epidemics, is often misdiagnosed due to symptom similarities with other arboviruses. Here, a portable and integrated nucleic acid-based diagnostic device, which combines reverse transcription-loop-mediated isothermal amplification and lateral-flow detection, was developed. The device is simple to use, precise, equipment-free, and highly sensitive, enabling rapid chikungunya virus identification. The result can be obtained by the naked eye within 40 min. The assay can effectively distinguish chikungunya virus from dengue virus, Japanese encephalitis virus, Zika virus, and yellow fever virus with high specificity and sensitivity as low as 598.46 copies mL−1. It has many benefits for the community screening and monitoring of chikungunya virus in resource-limited areas because of its effectiveness and simplicity. The platform has great potential for the rapid nucleic acid detection of other viruses. [ABSTRACT FROM AUTHOR]

A new asymmetric ligand, 5‐{3‐[5‐(4‐methylphenyl)‐1,3,4‐oxadiazol‐2‐yl]phenyl}‐2‐(pyridin‐3‐yl)‐1,3,4‐oxadiazole (L5), which contains two oxadiazole rings, was synthesized and characterized. The assembly of symmetric 2,5‐bis(pyridin‐3‐yl)‐1,3,4‐oxadiazole (L1) and asymmetric L5 with AgCO2CF3 in solution yielded two novel AgI complexes, namely catena‐poly[[di‐μ‐trifluoroacetato‐disilver(I)]‐bis[μ‐2,5‐bis(pyridin‐3‐yl)‐1,3,4‐oxadiazole]], [Ag2(C2F3O2)2(C12H8N4O)2]n or [Ag2(μ2‐O2CCF3)2(L1)2]n (1), and bis(μ3‐5‐{3‐[5‐(4‐methylphenyl)‐1,3,4‐oxadiazol‐2‐yl]phenyl}‐2‐(pyridin‐3‐yl)‐1,3,4‐oxadiazole)tetra‐μ3‐trifluoroacetato‐tetrasilver(I) dichloromethane monosolvate, [Ag4(C2F3O2)4(C22H15N5O2)2]·CH2Cl2 or [Ag2(μ3‐O2CCF3)2(L5)]2·CH2Cl2 (2). Complex 1 displays a one‐dimensional ring–chain motif, where dinuclear Ag2(CF3CO2)2 units alternate with Ag2(L1)2 macrocycles. This structure is different from previously reported Ag–L1 complexes with different anions. Complex 2 features a tetranuclear supramolecular macrocycle, in which each ligand adopts a tridentate coordination mode with the oxadiazole ring next to the p‐tolyl ring coordinated and that next to the pyridyl ring free. Two L5 ligands are bound to two Ag1 centres through two oxadiazole N and two pyridyl N atoms to form a macrocycle. The other two oxadiazole N atoms coordinate to the two Ag2 centres of the Ag2(O2CCF3)4 dimer. Each CF3CO2− anion adopts a μ3‐coordination mode, bridging the Ag1 and Ag2 centres to form a tetranuclear silver(I) complex. This study indicates that the donor ability of the bridging oxadiazole rings can be tuned by electron‐withdrawing and ‐donating substituents. The emission properties of ligands L1 and L5 and complexes 1 and 2 were also investigated in the solid state. [ABSTRACT FROM AUTHOR]

Three new one‐ (1D) and two‐dimensional (2D) CuII coordination polymers, namely poly[[bis{μ2‐4‐amino‐3‐(pyridin‐2‐yl)‐5‐[(pyridin‐3‐ylmethyl)sulfanyl]‐1,2,4‐triazole}copper(II)] bis(methanesulfonate) tetrahydrate], {[Cu(C13H12N5S)2](CH3SO3)2·4H2O}n (1), catena‐poly[[copper(II)‐bis{μ2‐4‐amino‐3‐(pyridin‐2‐yl)‐5‐[(pyridin‐4‐ylmethyl)sulfanyl]‐1,2,4‐triazole}] dinitrate methanol disolvate], {[Cu(C13H12N5S)2](NO3)2·2CH3OH}n (2), and catena‐poly[[copper(II)‐bis{μ2‐4‐amino‐3‐(pyridin‐2‐yl)‐5‐[(pyridin‐4‐ylmethyl)sulfanyl]‐1,2,4‐triazole}] bis(perchlorate) monohydrate], {[Cu(C13H12N5S)2](ClO4)2·H2O}n (3), were obtained from 4‐amino‐3‐(pyridin‐2‐yl)‐5‐[(pyridin‐3‐ylmethyl)sulfanyl]‐1,2,4‐triazole with pyridin‐3‐yl terminal groups and from 4‐amino‐3‐(pyridin‐2‐yl)‐5‐[(pyridin‐4‐ylmethyl)sulfanyl]‐1,2,4‐triazole with pyridin‐4‐yl terminal groups. Compound 1 displays a 2D net‐like structure. The 2D layers are further linked through hydrogen bonds between methanesulfonate anions and amino groups on the framework and guest H2O molecules in the lattice to form a three‐dimensional (3D) structure. Compound 2 and 3 exhibit 1D chain structures, in which the complicated hydrogen‐bonding interactions play an important role in the formation of the 3D network. These experimental results indicate that the coordination orientation of the heteroatoms on the ligands has a great influence on the polymeric structures. Moreover, the selection of different counter‐anions, together with the inclusion of different guest solvent molecules, would also have a great effect on the hydrogen‐bonding systems in the crystal structures. The coordination orientation of heteroatoms on ligands has a great influence on the formation of polymeric structures. Moreover, the selection of different counter‐anions, together with the inclusion of different guest solvent molecules, also has a great effect on the hydrogen‐bonding systems in the crystal structures. [ABSTRACT FROM AUTHOR]

Biodegradable polylactic acid (PLA) nanofibrous membranes (NFMs) hold great potential to address the increasing airborne particulate matter (PM) and dramatic accumulation of plastic/microplastic pollution. However, the field of PLA NFM-based filters is still in its infancy, frequently dwarfed by the bottlenecks regarding relatively low surface activity, poor electroactivity, and insufficient PM capturing mechanisms. This effort discloses a microwave-assisted approach to minute-level synthesis of dielectric ZIF-8 nanocrystals with high specific surface area (over 1012 m 2 /g) and ultrasmall size (∼240 nm), which were intimately anchored onto PLA nanofibers (PLA@ZIF-8) by a combined "electrospinning-electrospray" strategy. This endowed the PLA@ZIF-8 NFMs with largely increased electroactivity in terms of elevated dielectric coefficient (an increase of 202%), surface potential (up to 5.8 kV), and triboelectric properties (output voltage of 30.8 V at 10 N, 0.5 Hz). Given the profound control over morphology and electroactivity, the PLA@ZIF-8 NFMs exhibited efficient filtration of PM 0.3 (97.1%, 85 L/min) with a decreased air resistance (592.5 Pa), surpassing that of the pure PLA counterpart (88.4%, 650.9 Pa). This was essentially ascribed to realization of multiple filtration mechanisms for PLA@ZIF-8 NFMs, including enhanced physical interception, polar interactions, and electrostatic adsorption, and the unique self-charging function triggered by airflow vibrations. Moreover, perfect antibacterial performance was achieved for PLA@ZIF-8, showing ultrahigh inhibition rates of 99.9 and 100% against E. coli and S. aureus , respectively. The proposed hierarchical structuring strategy, offering the multifunction integration unattainable with conventional methods, may facilitate the development of biodegradable long-term air filters.