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Catalytic conversion of NO has long been a focus of atmospheric pollution control and diesel vehicle exhaust treatment. Rhodium is one of the most effective metals for catalyzing NO reduction, and understanding the nature of the active sites and underlying mechanisms can help improve the design of Rh-based catalysts towards NO reduction. In this work, we investigated the detailed catalytic mechanisms for the direct reduction of NO to N 2 by fullerene-supported rhodium clusters, C 60 Rh 4 + , with density functional theory calculations. We found that the presence of C 60 facilitates the smooth reduction of NO into N 2 and O 2 , as well as their subsequent desorption, recovering the catalyst C 60 Rh 4 + . Such a process fails to be completed by free Rh 4 + , emphasizing the critical importance of C 60 support. We attribute the novel performance of C 60 Rh 4 + to the electron sponge effect of C 60 , providing useful guidance for designing efficient catalysts for the direct reduction of NO.

Objective : The optimal probiotic supplementation in pregnant women has not been thoroughly evaluated. By employing a network meta-analysis (NMA) approach, we compared the effectiveness of different probiotic supplementation strategies for pregnant women. Methods : A comprehensive search across multiple databases was performed to identify studies comparing the efficacy of probiotic supplements with each other or the control (placebo) among pregnant women. Results : This NMA, including 32 studies, systematically evaluated 6 probiotic supplement strategies: Lactobacillus , Lacticaseibacillus rhamnosus and Bifidobacterium (LRB), Lactobacillus acidophilus and Bifidobacterium (LABB), Lactobacillus acidophilus , Lacticaseibacillus casei , and Bifidobacterium bifidum (LLB), multi-combination of four probiotics (MP1), and multi-combination of six or more probiotics (MP2). Among these strategies, LLB, MP1, and MP2 all contain LABB. The NMA findings showed that MP1 was the most effective in reducing fasting blood sugar (FBS) (surface under the cumulative ranking curve [SUCRA]: 80.5%). In addition, MP2 was the most efficacious in lowering the homeostasis model assessment of insulin resistance (HOMA-IR) (SUCRA: 89.1%). LABB was ranked as the most effective in decreasing low-density lipoprotein cholesterol (LDLC) (SUCRA: 95.5%), total cholesterol (TC) (SUCRA: 95.5%), and high-sensitivity C-reactive protein (hs-CRP) (SUCRA: 94.8%). Moreover, LLB was ranked as the most effective in raising total antioxidant capacity (TAC) (SUCRA: 98.5%). Conclusion : Multi-combination of probiotic strains, especially those strategies containing LABB, may be more effective than a single probiotic strain in glycolipid metabolism, inflammation, and oxidative stress of pregnant women.

The self-trapping nano-loop structures of [1]rotaxanes exhibited multiple Förster resonance energy transfer (FRET) patterns via dual and sequential locking/unlocking of pH-gated and UV exposure processes. As a tightened and constrained nano-loop in the acidic condition, dithienylethene (DTE) unit was locked in the highly bending open form to forbid ring closure upon UV irradiation.

Chiral organic-inorganic hybrid perovskites have gained extensive research interest due to their combination of chirality and the excellent optical, electrical and spin properties of perovskite materials, especially in two-dimensional hybrid perovskites. Herein, we report two-dimensional organic-inorganic perovskite enantiomeric ferroelectric [( R )-β-MPA] 2 CdCl 4 (1) and [( S )-β-MPA] 2 CdCl 4 (2) (MPA + =methylphenethylammonium). Their mirror relationships are verified by both circular dichroism (CD) and crystal structures. At the same time, the two exhibit very similar ferroelectricity and related properties, including high Curie temperature (343 K), large spontaneous polarization (4.65 μC cm -2 ), and low coercive force field (13 kV cm -1 ). Unusually, at room temperature the crystal phase is monoclinic with the space group C 2 and above the phase transition temperature it is triclinic with the space group P 1, which means that the symmetry decreases with the increase of temperature. In addition, it exhibits a flexible switchable SHG response, while [( R )-β-MPA] 2 CdCl 4 and [( S )-β-MPA] 2 CdCl 4 have wide band gaps of 4.21 and 4.26 eV, respectively, mainly contributed by inorganic CdCl 6 octahedra. This discovery opens a new way for the construction of two-dimensional enantiomeric molecular ferroelectrics.

Solid-state electrolyte (SSE) is crucial for a high-performance all-solid-state battery. Here, a new solid sodium electrolyte based on the ionic liquid EIMS-NaTFSI and one metal-organic framework (MOF) UiO-67-MIMS functionalized with zwitterion groups MIMS was obtained (UiO-67 and was assembled with 4,4'-biphenyldicarboxylate linker and cluster Zr 6 O 4 (OH) 4 ) (EIMS = 1-(1-ethyl-3-imidazolio)propane-3-sulfonate, NaTFSI = sodium bis(trifluoromethanesulfonyl)imide, MIMS = 1-(1-mthyl-3-imidazolio)propane-3-sulfonate). By contacting and pairing EIMS-NaTFSI (abbreviated as EN-1) to the MIMS group on the framework, EN-1 was directed and arranged along the channels within UiO-67-MIMS, forming a solid composite EN-1@UiO-67-MIMS with Bragg scatter, i.e. , a crystalline ionic liquid containing Na + salts (NaTFSI). Such an ionic liquid EN-1@UiO-67-MIMS bearing crystalline MOF matrix showed and preserved fast ion conduction (1.02 × 10 -2 S cm -1 ) at 150 °C even after 30 days, and exhibited 1-2 orders of magnitude higher conductivities than the bulk ionic liquid EN-1 within a wide temperature range, although the ion content in the latter was higher. The infinite pathway paved by the EN-1 arranged and contacted the MIMS along the channels within MOF well accounts for the fast ion transmission and the stability of the solid-state electrolyte. Such MOF-based crystalline ionic liquid provides a new strategy for developing high-performance solid-state electrolytes for ions.

A novel chromium(VI)-based compound, [(CH 3 CH 2 ) 3 N(CH 2 Cl)][CrO 3 Cl] (1), undergoes a high-temperature phase transition at around 340.9 K, accompanied by an ultra-large entropy change of 63.49 J mol -1 K -1 . Compound 1 exhibits a moderate ferroelectric polarization of 0.48 μC cm -2 and a remarkable CD signal. Strikingly, 1 occupies a narrow band gap of 2.22 eV, which is chiefly attributed to the inorganic [CrO 3 Cl] - tetrahedron. It is believed that these findings will contribute to an alternative pathway for the design of multifunctional ferroelectric materials, whose potential applications will be in semiconductors, energy storage, etc.

Low-dimensional chiral organic-inorganic hybrid metal halides have attracted a lot of attention in recent years due to their unique intrinsic properties, including having potential applications in optoelectronic and spintronic devices. However, low-dimensional chiral molecular ferroelectrics are very rare. In this paper, we report a novel zero-dimensional molecular ferroelectric (C 9 H 14 N) 2 CdBr 4 (C 9 H 14 N + = protonated 3-phenylpropylamine), which has obvious dielectric and thermal anomalies and shows a high Curie temperature at 395 K. It crystallizes in the P 2 1 space group at room temperature, showing a strong CD signal, large spontaneous polarization ( P s = 13.5 μC cm -2 ), and a clear ferroelectric domain. In addition, it also exhibits a flexible SHG response. The photoluminescence spectrum shows that 1 has broadband luminescence. At the same time, compound 1 has a wide band gap, which is mainly contributed to by the inorganic CdBr 4 tetrahedron. The high tunability of low-dimensional chiral molecular ferroelectrics also opens up a way to explore multifunctional chiral materials., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Enzyme-linked immunosorbent assays (ELISAs) are tests that uses antibody recognition and enzyme catalytic activity to identify a substance, and they have been widely used as a diagnostic tool in the clinic. However, performing an ELISA requires various liquid handling steps and long binding times. To solve this problem, we developed a magnetic microfluidic ELISA system (MMF-ELISA). Integration with nickel magnetic nanoparticles can streamline the ELISA process in a fully automated manner for Streptococcus pneumoniae detection. First, we synthesized paramagnetic surface-oxidized nickel nanoparticles (Ni/NiO NPs) to carry protein G. Then, we assembled a SUM290 (UlaG)-specific antibody on protein G. Finally, we integrated the NPs on a microfluidics chip for S. pneumoniae detection. The chip contains three different layers to trap the solutions; the bottom layer SiO 2 is patterned on hydrophobic polymers and integrated with the middle layer PDMS and the top layer PMMA. With Arduino and motor IC, we developed an automated platform for S. pneumoniae detection. Microfluidic ELISAs can reduce the manual handling and operation time. Furthermore, the developed system can be extended to multiple areas for ELISA-related assays. This economical, rapid and portable system may become a promising platform for sensing S. pneumoniae in clinical applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Metal-organic frameworks functionalized with Cd(ii) binding phages were for the first time fabricated for the isolation and preconcentration of ultra-trace cadmium. Highly specific Cd(ii) binding phages were screened through biological panning from a phage display peptide library. Thereafter, chloroauric acid (HAuCl 4 ) was reduced by the phages to provide phage-stabilized gold nanoparticles (AuNPs). The phage-AuNP networks were then assembled onto the metal-organic framework UiO66-NH 2 to serve as an affinity probe for the selective recognition and isolation of ultra-trace cadmium. 2.0 μg L -1 Cd 2+ was selectively captured by the derived UiO66-NH 2 @phage composite with an adsorption efficiency of 100%. UiO66-NH 2 @phage exhibits favorable anti-interference capability against the coexisting species. It ensures highly selective and sensitive quantification of ultra-trace cadmium with detection by graphite furnace atomic absorption spectrometry (GFAAS). An enrichment factor of 17.4 was obtained along with a limit of detection (LOD) of 3.9 ng L -1 within a linear range of 0.01-0.35 μg L -1 . The procedure was further validated by analyzing cadmium content in a certified reference material (CRM, simulated water, GBW08608) and a series of environmental water samples. In general, the present study provides a new protocol for the development of novel adsorbents toward the target by biopanning to regulate the selectivity.

Hyaluronic acid (HA) is a ubiquitous glycosaminoglycan in the extracellular matrix and a ligand of CD44, a transmembrane glycoprotein that is important in cell migration. Crystal and NMR studies found a hexasaccharide of the pattern (GlcA-GlcNAc)3 as the shortest HA that could bind to CD44, but molecular dynamics simulations indicated that a tetrasaccharide of the pattern (GlcNAc-GlcA)2 is the key structure interacting with CD44. Access to oligomers with such a repeat pattern is crucial in binding studies with CD44. Here we developed a synthetic procedure to afford the HA oligosaccharides with the GlcNAc-GlcA repeating unit and measured the binding interaction between these sugars and human CD44 by isothermal titration calorimetry (ITC). During the chemical synthesis, we successfully generated the β-glycosidic bond in the absence of neighbouring group participation and overcome the issues in the oxidation step. In addition, ammonia-free dissolving metal reduction for debenzylation and azido reduction has been applied in carbohydrate synthesis for the first time. ITC analysis revealed that the HA tetrasaccharide (GlcNAc-GlcA)2 could indeed interact and bind to the human CD44.

A [3 + 2] annulation protocol for the construction of N-substituted indazolo[3,2-a]isoquinolines starting from benzynes and C,N-cyclic azomethine imines was developed. A diverse range of highly functionalized products indazolo[3,2-a]isoquinolines featuring an indazole scaffold can be easily accessed via a one-step reaction under mild conditions, and they show good anti-proliferative activity on cancer cells.

Magnesium (Mg) is frequently used as a biocompatible implantable material in the human body, but real-time detection of its corrosion state is not well understood. Fortunately, previous studies of triboelectric nanogenerators (TENG) as self-driven sensors in many fields have proposed solutions for this problem. In this work, Mg-based TENG was prepared as a self-driven sensor to detect the corresponding corrosion state of Mg treated by micro-arc oxidation (MAO-Mg). Mg-based sheets and polydimethylsiloxane (PDMS) film were used as triboelectric materials. The output of TENG was optimal under 350 V-800 Hz micro-arc oxidation (MAO) treatment of Mg, and the V oc , I sc and Q sc were 48.5 V, 35.3 μA and 44.2 nC, which were respectively 2.42, 3.42 and 3.27 times that of the untreated devices. Moreover, a linear relationship was found in simulated body fluid (SBF) immersion tests, showing that the rates of decrease in I sc and V oc were respectively 3.48 and 2.74 times the weight reduction rates of MAO-Mg sheets, indicating that our sensors successfully detected the corrosion of MAO-Mg. This work will lay a preliminary foundation for real-time detection of Mg as an implant in the human body (as do other implantable materials), and demonstrates a potential new application for TENG in the biomedical field., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

For many decades, astronomers have searched for biological molecules, including amino acids, in the interstellar medium; this endeavor is important for investigating the hypothesis of the origin of life from space. The space environment is complex and atomic species, such as nitrogen and oxygen atoms, are widely distributed. In this work, the reactions of eight typical deprotonated amino acids (glycine, alanine, cysteine, proline, aspartic acid, histidine, tyrosine, and tryptophan) with ground state nitrogen and oxygen atoms are studied by experiment and theory. These amino acid anions do not react with nitrogen atoms. However, the reactions of these ions with oxygen atoms show an intriguing variety of ionic products and the reaction rate constants are of the order of 10 -10 cm 3 s -1 . Density functional calculations provide detailed mechanisms of the reactions, and demonstrate that spin conversion is essential for some processes. Our study provides important data and insights for understanding the kinetic and dynamic behavior of amino acids in space environments.

We report a novel 'fluorescent dopamine' that possesses essential features of natural dopamine. Our method is simple and is readily extended to monoamine neurotransmitters such as L-norepinephrine, serotonin and GABA, providing a more practical approach. Because of its compatibility with sensitive fluorescent measurements, we envisage that our approach will have a broad range of applications in neural research.

A new approach to immobilize zwitterionic molecules rapidly and highly efficiently on a gold surface applies aniline-based electrodeposition. The zwitterion-functionalized antifouling surface enables a decrease of the adsorption of non-specific proteins by 95% from fetal bovine serum (FBS, 10%).

This study shows the modification of the surface of polymer-layered glass substrates to form biofunctional micropatterns through femtosecond laser ablation in an aqueous solution. Domains of micrometer size on a substrate can be selectively converted from proteinphobic (resistant to protein adsorption) to proteinphilic, allowing patterning of protein features under physiological aqueous conditions. When femtosecond laser pulses (800 nm, 1 kHz, 200-500 nJ per pulse) were focused on and scanned on the substrate, which was glass covered with the proteinphobic polymer 2-methacryloyloxyethylphosphorylcholine (MPC), the surface became proteinphilic. Surface analysis by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) reveals that the laser ablates the MPC polymer. Extracellular matrix (ECM) proteins were bound to the laser-ablated surface by physisorption. Since femtosecond laser ablation is induced under physiological aqueous conditions, this approach can form micropatterns of functional ECM proteins with minimal damage. This method was applied to pattern collagen, laminin, and gelatin on the substrate. Removal of an ECM protein from the substrate followed by replacement with another ECM protein was achieved on demand at a specific location and time by the same laser ablation method. Living cells adhered to the fabricated domains where ECM proteins were arranged. The modification of patterning during cell culture was used to control cell migration and form arrays of different cells.

According to our recent studies on the nonequilibrium solvation, the solvent reorganization energy is found to be the cost of maintaining the residual polarization P', which equilibrates with the extra electric field E(ex). On the basis of this solvent reorganization energy and the well-established equilibrium solvation energy, a novel and reasonable expression for the spectral shift of the electronic absorption spectra is proposed in this work. Furthermore, the two lowest transitions of uracil in aqueous solution are investigated as test cases with the TDDFT/6-311++G** method. The obtained spectral shift is 0.48 eV for n → π* transition and -0.14 eV for π → π* transition, agreeing well with available experimental results. The contributions to the shift are discussed and the electrostatic plus polarization components are found to be crucial for the electronic absorption spectra of uracil in aqueous solution.