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Three-dimensional (3D) network provide a promising platform for construction of high sensitive electrochemical immunosensor due to the benefits of high specific surface area and electron mobility. Herein, a sensitive label-free electrochemical immunosensor based on Au nanoparticles modified Ni-B nanosheets/graphene matrix was constructed to detect diethylstilbestrol (DES). The 3D network not only could increase the electron transport rate and surface area, but also could provide confinement area, which is conducive to increases the collision frequency with the active site. Moreover, Au NPs also have good biocompatibility, which is beneficial for ligating antibodies. Benefiting from the 3D network structure and Au collective effect, the electrochemical immunosensor possess sterling detection ability with wide linear response range (0.00038-150 ng/mL) and low detection limit (31.62 fg/mL). Moreover, the constructed immunosensor can also be extend to detect DES in Tap-water and river water. This work may provide a novel material model for the construction of high sensitive immunosensor.

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Cytokeratin 19 fragment antigen 21-1 (CYFRA21-1) is a protein fragment released into the bloodstream during the death of lung epithelial cells, serving as a predictive biomarker in diagnosing non-small cell lung cancer (NSCLC) and need to be accurately detected. Herein, a dual-responsive label-free electrochemical immunosensor was developed based on a three-dimensional ordered interconnecting macroporous carbon skeleton material modified with gold-cobalt nanoparticles (Au/Co NPs-3D MCF) to detect cytokeratin-19 fragment (CYFRA21-1). The three-dimensional ordered interconnect macroporous structure, by providing a high specific surface area and an electrochemically active area, not only enhances the electron transport channel and reduces mass transfer resistance, but also offers a confined region that elevates the collision frequency with the active site. In addition to exhibiting excellent biocompatibility for antibody binding, gold-cobalt nanoparticles contribute significantly to the overall robustness of the immunosensor. By capitalizing on the 3D network structure and collective effect of Au and Co NPs, the Au/Co NPs-3D MCF immunosensors exhibit exceptional response signals in both chronocurrent testing and square-wave voltammetry, allowing for a wide linear response range of 0.0001-100 ng/mL and a low detection limit. Moreover, the constructed immunosensor is capable of detecting CYFRA21-1 in human serum and has the potential for further extension to detect multiple biomarkers. This work opens up new avenues for the construction of other highly selective 3D network immunosensors.

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On the premise of cleanliness and stability, improving the catalytic efficiency for the oxygen reduction reaction in the electrode reaction of fuel cells and metal-air batteries is of vital importance. Studies have shown that heteroatom doping and structural optimization are efficient strategies. Herein, a single-atom-like B-N3 configuration in carbon is designed for efficient oxygen reduction reaction catalysis inspired by the extensively studied transition metal M-Nx sites, which is supported on the ordered macroporous carbon prepared by utilizing a hydrogen-bonded organic framework as carbon and nitrogen sources and SiO2 spheres as a template. The co-doping of B/N and ordered macroporous structures promote the metal-free material high oxygen reduction catalytic performance in alkaline media. DFT calculations reveal that the B-N3 structure played a key role in enhancing the oxygen reduction activity by providing rich favorable *OOH and *OH adsorption sites on the B center. The promoted formation of *OH/*OOH intermediates accelerated the electrocatalyst reaction. This study provides new insights into the design of single-atom-like nonmetallic ORR electrocatalysts and synthesis of ordered macroporous carbons based on hydrogen-bonded organic frameworks.

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Three-dimensional cubic ordered mesoporous carbon with chitosan (Ia3d-CS), which was synthesized via exothermic reaction between liquid potassium and carbon monoxide gas, was coated on the active carbon (AC) electrode as a capacitive deionization (CDI) disinfection electrode. The results showed that Ia3d-CS-2 as CDI electrode exhibited the quick ion diffusion and strong charge transfer performance, due to the three-dimensional pore structure and specific surface area. The electrode of Ia3d-CS-2 displayed a specific capacity of 191.22 F/g at a scan rate of 100 mV·s-1 in 0.5 M NaCl aqueous solution. In a CDI recycling system, Ia3d-CS-x electrode showed good cyclic stability, and the electrosorption capacity of Ia3d-CS-2 electrode can achieve 1.31 mg/g at 1.2 V in 100 mg/l NaCl aqueous solutions. Subsequently, Ia3d-CS-2 electrode had an excellent disinfection efficiency of killing about 99.99% Escherichia coli within 30 min during the CDI process at applied 1.2 V. Considering those excellent properties of the fabricated Ia3d-CS-x electrode, which should be a better candidate for high-performance deionization application.

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In our study, soluble starch was applied as a novel carbon source for preparing three-dimensional ordered macroporous carbon (3DOMC) using monodisperse silica nanospheres as the hard template. The 3DOMC was used as an insoluble drug carrier when it was found that it could markedly improve the water solubility of felodipine (FDP). The structural features of 3DOMC were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The 3DOMC structure was found to have a higher drug loading than microporous and mesoporous structures, and the interconnected nanostructure effectively inhibited the formation of drug crystals. FDP, belonging to the Biopharmaceutics Classification System II (BCSII), was chosen as the model drug and was loaded into the 3DOMC structure by solvent evaporation. The state of FDP in the 3DOMC structure was characterized by powder X-ray diffractometry (PXRD), differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). The results obtained showed that FDP was present in the pores in an amorphous or microcrystalline state. In vivo and in vitro experiments indicated that 3DOMC could significantly improve the drug dissolution rate, but the FDP-3DOMC self-made common tablets had the disadvantage of a burst effect. For this reason, osmotic pump technology was used to control the drug release rate. We developed a potentially useful insoluble drug carrier for pharmaceutical applications.

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3-D ordered macroporous carbon with different polymer coatings were developed as new oral vaccine immunological systems. Poly dimethyl diallyl ammonium (PDDA), polyethyleneimine (PEI) and chitosan (CTS), three different polymers with electropositive or adsorption-promoting properties, were chosen as the coating materials to endow the vaccine delivery systems with different surface properties. The bovine serum albumin (BSA) was used as a model vaccine. The three different polymer coated systems exhibited similar release rate which minimized the influence of release rate. The measured value of immunoglobulin G (IgG) titers suggested that the sustained release rate of BSA from polymer coated systems exhibited no strengthened effect on the immune response but could delay the appearance of the peak of the IgG titers compared with uncoated system. The electrostatic attraction between the mucosal and positively charged carrier would be useful during the whole immune experiment. In addition, using the coating material with the ability of enhancing mucosal adsorption was important in the mid-late period of immune. The immunoglobulin A (IgA) titers induced by the polymer coated systems were significantly higher than that induced by the oral BSA solution or i.m. BSA with Freund's complete adjuvant (FCA) which suggested the successful mucosal immune response of the three different coated systems. Overall, this work provides valuable information for the development of oral vaccine delivery system.

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