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A copper/polydimethylsiloxane (Cu/PDMS) microfluidic chip was designed to synthesize SERS substrates through a displacement reaction between silver and copper in microfluidic channels to form a microfluidic SERS nanoparticles (AgNPs)/Cu chip. This SERS substrate fabrication method doesn't require complex manufacturing processes or expensive equipment, and it can be achieved at room temperature in just 4 min. Meanwhile, the AgNPs grown on copper foil could offer ample hot spots, effectively boosting Raman signals of target molecules, and the enhancement factor (EF) was 5.12 × 107 for methylene blue, 4.08 × 107 for crystal violet, and 4.81 × 105 for sulfadiazine. The chip could be reused at least 9 times with consistent signal performance. Combined with the concentration gradient microchannel network design, we could establish the standard curve for samples through one injection on a single chip. A rapid SERS method for detecting sulfadiazine in aquatic products was developed. The linear range for sulfadiazine analysis was 75.0–1000 μg L−1 with a limit of detection of 28.4 μg L−1. Sulfadiazine was found in aquatic products (43.8 μg kg−1), with recovery rates ranging from 82.7% to 110%. The result was validated using high-performance liquid chromatography, showing a relative error of 9.3%. The entire detection procedure could be completed in just 20 min to detect sulfadiazine. These results demonstrate that the developed SERS method is fast, accurate, and reliable for analysis of sulfadiazine in aquatic products. [ABSTRACT FROM AUTHOR]

Iron-modified Ni(OH)2/NiSe2 enhances oxygen vacancies, expanding the electrochemically active surface area, which exhibiting superior selectivity and stability in urea oxidation reaction, outperforming pristine Ni(OH)2@NiSe2. It also demonstrates superior catalytic performance in the oxidation reactions of other small molecules. [ABSTRACT FROM AUTHOR]

Hydrogel-based conductive materials for smart wearable devices have attracted increasing attention due to their excellent flexibility, versatility, and outstanding biocompatibility. This review presents the recent advances in multifunctional conductive hydrogels for electronic devices. First, conductive hydrogels with different components are discussed, including pure single network hydrogels based on conductive polymers, single network hydrogels with additional conductive additives (i.e., nanoparticles, nanowires, and nanosheets), double network hydrogels based on conductive polymers, and double network hydrogels with additional conductive additives. Second, conductive hydrogels with a variety of functionalities, including self-healing, super toughness, self-growing, adhesive, anti-swelling, antibacterial, structural color, hydrophobic, anti-freezing, shape memory and external stimulus responsiveness are introduced in detail. Third, the applications of hydrogels in flexible devices are illustrated (i.e., strain sensors, supercapacitors, touch panels, triboelectric nanogenerator, bioelectronic devices, and robot). Next, the current challenges facing hydrogels are summarized. Finally, an imaginative but reasonable outlook is given, which aims to drive further development in the future. [ABSTRACT FROM AUTHOR]

Medical research reveals that keeping the skin surface dry can effectively prevent a variety of fungal skin diseases. Therefore, it is of great practical significance to develop a light, thin, comfortable and breathable functional garment fabric with efficient one-way water transmission for people's requirements. Here, we successfully prepared a three-layer stacking sandwich coating to construct a Janus nonwoven material with efficient unidirectional water transport function, viz. PDMS-ormosil-PDMS@nonwoven fabric (PDMS-ormosil-PDMS@NF). Theoretical analysis showed that the loading of ormosil particles could enhance the surface roughness, while PDMS could strengthen the hydrophobic properties and bondability between the ormosil particles and fabric, thus acting as an environmentally friendly fluorine-free treating agent. The results revealed that the hydrophilic–hydrophobic PDMS-ormosil-PDMS@nonwoven fabric maintained excellent hydrophobic stability and good air permeability even after abrasion, which solved the existing problems of aerogel poor deposition and PDMS poor permeability, benefiting the application of textiles with unidirectional water transport performance. [ABSTRACT FROM AUTHOR]

Position- and orientation-controllable micropatterned ZnO/TiO2nanostructures with different morphologies have been fabricated using a novel and versatile superhydrophilic/superhydrophobic template. Scanning electron microscopy, optical microscopy, electron probe microanalysis and X-ray diffraction were systematically used to confirm the successful fabrication of the patterns and to characterize the structure and morphology. The selective growth of ordered ZnO nanostructured patterns on the TiO2nanotube surface employs a simple photocatalytic lithography technique with mild reaction conditions and in the absence of seeds and noble metal catalysts. The photoelectrical properties of the micropatterned ZnO/TiO2nanocomposites with unique heterojunction structure and different density and orientation of the ZnO crystals were also investigated. It is expected that this novel micropatterned technique based on the superhydrophilic/superhydrophobic template will become a powerful tool for fabricating various types of micropatterned nanomaterials and devices. [ABSTRACT FROM AUTHOR]

Condensation of an (S)- or (R)-BINOL-derived dialdehyde and tris(2-aminoethyl)amine produced chiral [2+3] imine cages, which were further reduced to furnish more stable chiral amine cages and applied in the enantioselective recognition of (1R,2R)- and (1S,2S)-1,2-diaminocyclohexane. [ABSTRACT FROM AUTHOR]

We report a new and efficient protocol for rapid electrodeposition of a gold–Prussian blue ((Au–PB)REd) nanocomposite with ultrahigh electroactivity on an Au electrode by cyclic voltammetry in 0.1 M aqueous K2SO4 containing 1 mM K3Fe(CN)6, 1 mM HAuCl4, and 0.1 mM Fe2(SO4)3, and an electrochemical quartz crystal microbalance and scanning electron microscopy were utilized to investigate the electrodeposition. The (Au–PB)REd/Au electrode was then cast-coated with a urate oxidase (UOx)–poly(anilineboronic acid) (PABA)–Pt nanoparticle (PtNP) bionanocomposite and chitosan (CS) for high-performance amperometric biosensing of uric acid (UA) in the dual-potential mode. The UOx–PABA–PtNP bionanocomposite was prepared through chemical oxidation of anilineboronic acid (ABA) by sodium chloroplatinate in the presence of UOx. The thus-fabricated CS/UOx–PABA–PtNP/(Au–PB)REd/Au enzyme electrode worked well under optimized conditions through both oxidation and reduction determination of enzyme-generated H2O2, which responded linearly to UA concentrations from 0.3 μM to 0.65 mM with a sensitivity of 223 μA mM−1 cm−2 and a limit of detection (LOD) of 0.2 μM (0.7 V vs. SCE), and from 0.2 μM to 0.25 mM with a sensitivity of 247 μA mM−1 cm−2 and a LOD of 0.1 μM (−0.05 V vs. SCE), being superior to most analogues hitherto reported for biosensing of UA. [ABSTRACT FROM AUTHOR]