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Lightweight structural materials are commonly used as effective fillers for advanced composites with high toughness. This study focused on enhancing the toughness of direct‐spun carbon nanotube yarns (CNTYs) by controlling the micro‐textural structure using a water‐gap‐based direct spinning. Drawing inspiration from the structural features of natural spider silk fibroin, characterized by an α‐helix in the amorphous region and β‐sheet in the crystalline region, multiscale bundles within CNTYs are reorganized into a unique nano‐coil‐like structure. This nano‐coiled structure facilitated the efficient dissipation of external mechanical loads through densification with the rearrangement of multiscale bundles, improving specific strength and strain. The resulting CNTYs exhibited exceptional mechanical properties with toughness reaching 250 J g−1, making them promising alternatives to commercially available fibers in lightweight, high‐toughness applications. These findings highlight the significance of nano‐coiling engineering for emulating bio‐inspired micro‐textural structures, achieving remarkable enhancement in the toughness of CNTYs. [ABSTRACT FROM AUTHOR]

With increasing demands on electromagnetic interference (EMI) shielding, considerable efforts have been devoted to realizing viable EMI shielding materials with processability and stability. Here, we report the first example of a large-scalable, ultrastable, and transparent film based on conductive metal–organic frameworks (cMOFs) for EMI shielding. A cobalt-based cMOF is uniformly grown on a direct-spun double-walled carbon nanotube film (DWNTF), maximizing both conductivity and EMI shielding effectiveness (SE). Furthermore, the hybrid films preserve their high EMI SE under long-term exposure, high temperature, repeated mechanical bending, and even immersion in artificial seawater, which is the most detrimental operating condition for EMI shielding materials. This report can offer new design guidance for viable EMI shielding materials by integrating scalability and stability with high EMI SE. [ABSTRACT FROM AUTHOR]

Achieving the high theoretical energy density (∼3500 W h kg−1) of Li–O2 batteries involves maximizing the electrochemically active surface area (EASA) of the electrodes. Carbon nanotubes (CNTs) have been widely adopted for Li–O2 electrodes but their EASA is limited by their electrolyte-phobic surface nature and the strong van der Waals interaction between CNTs. To increase the affinity between CNT-based electrodes and the electrolyte without decreasing CNT chemical stability, CNT buckypapers are functionalized with 3,5-bis(trifluoromethyl)phenylmaleimide. The solubility parameters of the electrolyte and CNTs are considered so that the maleimide groups increase the affinity between the electrode and electrolyte and the 3,5-bis(trifluoromethyl)phenyl groups protect the maleimide groups from decomposition. The functionalized CNT cathode exhibits a 58% greater discharge capacity and a 50% increased cyclability compared to the pristine CNT cathode when a 1 : 2.5 weight ratio of CNT to electrolyte was used due to an increased EASA and steric hindrance effect. Finally, a 3D folded Li–O2 cell is fabricated using the functionalized CNT-based cathode and demonstrated 30 cycles at 100 W h kgcell−1 cutoff. These results clearly show that high energy density and long cycling performance of Li–O2 batteries can be achieved even with a much reduced amount of electrolyte by increasing the affinity between CNT-based electrodes and the electrolyte. [ABSTRACT FROM AUTHOR]

Li-O 2 batteries have attracted considerable attention for several decades due to their high theoretical energy density (>3400 Wh/kg). However, it has not been clearly demonstrated that their actual volumetric and gravimetric energy densities are higher than those of Li-ion batteries. In previous studies, a considerable quantity of electrolyte was usually employed in preparing Li-O 2 cells. In general, the electrolyte was considerably heavier than the carbon materials in the cathode, rendering the practical energy density of the Li-O 2 battery lower than that of the Li-ion battery. Therefore, air cathodes with significantly smaller electrolyte quantities need to be developed to achieve a high specific energy density in Li-O 2 batteries. In this study, we propose a core-shell-structured cathode material with a gel-polymer electrolyte layer covering the carbon nanotubes (CNTs). The CNTs are synthesized using the floating catalyst chemical vapor deposition method. The polymeric layer corresponding to the shell is prepared by the layer-by-layer (LbL) coating method, utilizing Li-Nafion along with PDDA-Cl [poly(diallyldimethylammonium chloride)]. Several bilayers of Li-Nafion and PDDA, on the CNT surface, are successfully prepared and characterized via X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The porous structure of the CNTs is retained after the LbL process, as confirmed by the nitrogen adsorption-desorption profile and BJH pore-size distribution analysis. This porous structure can function as an oxygen channel for facilitating the transport of oxygen molecules for reacting with the Li ions on the cathode surface. These polymeric bilayers can provide an Li-ion pathway, after absorbing a small quantity of an ionic liquid electrolyte, 0.5 M LiTFSI EMI-TFSI [1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide]. Compared to a typical cathode, where only liquid electrolytes are employed, the total quantity of electrolyte in the cathode can be significantly reduced; thereby, the overall cell energy density can be increased. A Li-O 2 battery with this core-shell-structured cathode exhibited a high energy density of approximately 390 Wh/kg, which was assessed by directly weighing all of the cell components together, including the gas diffusion layer, the interlayer [a separator containing a mixture of LiTFSI, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PYR-14), and PDDA-TFSI], the lithium anode, and the LbL-CNT cathode. The cycle life of the LbL-CNT-based cathode was found to be 31 cycles at a limited capacity of 500 mAh/g carbon . Although this is not an excellent performance, it is almost 2 times better than that of a CNT cathode without a polymer coating.

Purpose: Tuberculosis (TB) is a major infectious disease and is responsible for two million deaths annually. For the identification and quantitation of Mycobacterium tuberculosis (M. tuberculosis), a causative agent of TB, a sandwich enzyme-linked immunosorbent assay (ELISA) against the MPT64 protein of M. tuberculosis, an antigen marker of the M. tuberculosis complex, was developed., Materials and Methods: The MPT64 protein was expressed, and anti-MPT64 monoclonal antibodies were prepared. A sandwich ELISA was established using recombinant MPT64 protein and anti-MPT64 monoclonal antibodies. The sandwich MPT64 ELISA was evaluated using reference and clinical mycobacterial strains., Results: The sandwich MPT64 ELISA detected MPT64 protein from 2.1 ng/mL to 250 ng/mL (equivalent to 1.7×10⁴ CFU/mL and 2.0×10⁶ CFU/mL). All 389 clinical M. tuberculosis isolates tested positive in the sandwich MPT64 ELISA (sensitivity, 100%), and the assay showed no cross reactivity to any tested nontuberculous mycobacterial strain (specificity, 100%)., Conclusion: The sandwich MPT64 ELISA is a highly sensitive and quantitative test for MPT64 protein, which can identify M. tuberculosis.

Background: Chagas' disease is caused by Trypanosoma cruzi, a protozoan parasite, which is transmitted by blood-sucking bugs or through blood transfusion or organ transplantation. It is endemic in Central and South America. The objective of this study was to compare the performance of immunochromatographic SD Bioline Chagas Ab Rapid (Standard Diagnostics, Korea) with three immunochromatographic kits for the detection of antibodies to T. cruzi., Methods: A total of 320 serum specimens (140 positive and 180 negative) from National Reference Laboratory for Chagas and Leishmaniasis (NRLCL, Honduras) were used for the evaluation of four different test kits: SD Bioline Chagas Ab Rapid, Chagas Stat-Pak Assay (Chembio Diagnositc Systems, USA), OnSite Chagas Ab Rapid test-Cassette (CTK Biotech, USA), and Trypanosoma Detect Rapid Test (InBios International, USA). The results of four kits were compared with those of NRLCL. Cross-reactivity with other parasites was also evaluated., Results: Compared with the results of NRLCL, sensitivity and specificity were 99.3% and 100% for both of SD and Chembio kits, 97.2% and 100% for InBios kit, and 97.9% and 98.8% for CTK kit. None of other parasites showed cross-reactivity., Conclusions: SD Bioline Chagas Ab Rapid kit showed test results highly correlating with those of National Reference Laboratory for Chagas and Leishmaniasis. It can be used for a rapid detection of Chagas' disease in endemic region and monitoring the disease among overseas travelers in Korea.