Bifunctional K3PW12O40/Graphene Oxide-Modified Separator for Inhibiting Polysulfide Diffusion and Stabilizing Lithium Anode.

Lithium-sulfur (Li-S) batteries are considered as promising candidates for next-generation batteries due to their high theoretical energy density. However, the practical application of Li-S batteries is still hindered by several challenges, such as the polysulfide shuttle and the growth of lithium dendrites. Herein, we introduce a bifunctional K3PW12O40/graphene oxide-modified polypropylene separator (KPW/GO/PP) as a highly effective solution for mitigating polysulfide diffusion and protecting the lithium anode in Li-S batteries. By incorporating KPW into a densely stacked nanostructured graphene oxide (GO) barrier membrane, we synergistically capture and rapidly convert lithium polysulfides (LiPSs) electrochemically, thus effectively suppressing the shuttling effect. Moreover, the KPW/GO/PP separator can stabilize the lithium metal anode during cycling, suppress dendrite formation, and ensure a smooth and dense lithium metal surface, owing to regulated Li+ flux and uniform Li nucleation. Consequently, the constructed KPW/GO/PP separator delivered a favorable initial specific capacity (1006 mAh g-1) and remarkable cycling performance at 1.0 C (626 mAh g-1 for up to 500 cycles with a decay rate of 0.075% per cycle).

Keggin-type polyoxometalate-based crown ether complex for lithium-sulfur batteries.

A novel supramolecular complex Li3Cl[(HPW12O40)(H24C12O6)3(CH3CN)2] {CR-PW12} was confirmed first to apply as a sulfur host in lithium-sulfur batteries. The {CR-PW12}@S cathode exhibits a reversible capacity of 1120 mA h g-1 at 1.0 C and excellent cycle stability.

Three-dimensional nano assembly of nickel cobalt sulphide/polyaniline@polyoxometalate/reduced graphene oxide hybrid with superior lithium storage and electrocatalytic properties for hydrogen evolution reaction.

Engineering hierarchical nanostructures with enhanced charge storage capacity and electrochemical activity are vital for the advancement of energy devices. Herein, a highly ordered mesoporous three-dimensional (3D) nano-assembly of Nickel Cobalt Sulphide/Polyaniline @Polyoxometalate/Reduced Graphene Oxide (NiCo2S4/PANI@POM/rGO) is prepared first time via a simple route of oxidative polymerization followed by a hydrothermal method. Morphological analysis of the resulting hybrid reveals the sheet-like structures containing a homogeneous assembly of PANI@POM and NiCo2S4 on the graphene exterior maintaining huge structural integrity, large surface area and electrochemically active centres. The electrochemical analysis of the nanohybrid as the anode of the lithium-ion battery (LIB) has delivered ultra-huge reversible capacity of 735.5 mA h g-1 (0.1 A g-1 after 200 cycles), superb capacity retention (0.161% decay/per cycle at 0.5 A g-1 for 1000 cycles), and significant rate capability (355.6 mA h g-1 at 2 A g-1). The hydrogen evolution reaction (HER) measurement also proves remarkable activity, extremely low overpotential and high durability. The extraordinary performance of the nanohybrid is due to the presence of abundant electroactive centres, high surface area and a large number of ion exchange channels. These outstanding results prove the advantages of a combination of NiCo2S4, graphene sheets, and PANI@POM in energy devices.

Electrochemistry/Photoelectrochemistry-Based Immunosensing and Aptasensing of Carcinoembryonic Antigen.

Recently, electrochemistry- and photoelectrochemistry-based biosensors have been regarded as powerful tools for trace monitoring of carcinoembryonic antigen (CEA) due to the fact of their intrinsic advantages (e.g., high sensitivity, excellent selectivity, small background, and low cost), which play an important role in early cancer screening and diagnosis and benefit people's increasing demands for medical and health services. Thus, this mini-review will introduce the current trends in electrochemical and photoelectrochemical biosensors for CEA assay and classify them into two main categories according to the interactions between target and biorecognition elements: immunosensors and aptasensors. Some recent illustrative examples are summarized for interested readers, accompanied by simple descriptions of the related signaling strategies, advanced materials, and detection modes. Finally, the development prospects and challenges of future electrochemical and photoelectrochemical biosensors are considered.

A supramolecular complex of hydrazide-pillar[5]arene and bisdemethoxycurcumin with potential anti-cancer activity.

Pillar[5]arene complexes of the naturally occurring compound bisdemethoxycurcumin (BDMC) were acquired for improving the water solubility and stability of BDMC. As a family member of curcuminoid compounds, BDMC has many interesting therapeutic properties. However, its low aqueous solubility and stability resulted in poor availability and restricted the clinical efficacy. Pillar[5]arenes with hydrophilic ends and a hydrophobic cavity could include with BDMC based on size matching. The synthesized hydrazide-pillar[5]arene (HP5A) and BDMC had a strong host-guest interaction with a 1:1 binding stoichiometry. Furthermore, the HP5A âŠƒ BDMC complex could self-assemble into well-defined fibers in water/ethanol solution. This supramolecular complex worked well in vitro for inhibiting the proliferation of hepatoma carcinoma cells HepG2. Remarkably, this method of complexation with pillar[5]arenes visibly reduced the undesirable side effects on normal cells without weakening the anti-cancer activity of the drugs. We expected that the obtained host-guest complex and fibrous assembly would provide a promising platform for delivering drugs with low water solubility.

Exploring Anticancer Activities and Structure-Activity Relationships of Binuclear Oxidovanadium(IV) Complexes.

Dimeric mixed-ligand oxidovanadium complexes [V2O2(1,3-pdta)(bpy)2]·9H2O (1) and [V2O2(1,3-pdta)(phen)2]·6H2O (2) feature a symmetric binuclear structure bridged by 1,3-pdta, which is different from our previous reported asymmetric binuclear complex [V2O2(edta)(phen)2]·11H2O (3).In this study, a wide range of analytical techniques were carried out to fully characterize the complexes 1 and 2 and further investigate their structural stabilities. Density functional theory calculations of 1 and 2 also suggest that they might have good reactivity with biomolecules as anticancer agents. To assess and screen the antitumor activities of compounds 1-3 together with their four corresponding monomeric complexes [VO(ida)(phen)], [VO(ida)(bpy)], [VO(OH)(phen)2]Cl, and [VO(Hedta)]-, we have performed in vitro experiments with hepatocellular carcinoma HepG2 and SMMC-7721 cell lines by MTT analyses. Complex 2 was found to have the highest inhibitory potency against the growth of HepG2 and SMMC-7721 cells (IC50 = 2.07 ± 0.72 µM for HepG2; 13.00 ± 3.06 µM for SMMC-7721) compared to other compounds. The structure-activity relationship studies showed that the antitumor effect of compound 2 is higher than that of other compounds. After studying the monomeric compounds of 1-3, their effects were also ranked. Moreover, complex 2 displayed stronger binding affinity toward calf thymus DNA (Kb = 5.71 × 104 M-1) and cleavage activities than the other complexes (Kb = 1.34 × 104 M-1 for 1 and 5.22 × 104 M-1 for 3, respectively). We further extended the cellular mechanisms of drug action and found that 2 could block DNA synthesis and cell division of HepG2 and 7721 cells and further induce apoptosis by flow cytometry assays. In short, these results indicate that binuclear oxidovanadium compounds could have potential as simple, effective, and safe antitumor agents.

Correction: Transition metal substituted sandwich-type polyoxometalates with a strong metal-C (imidazole) bond as anticancer agents.

Correction for 'Transition metal substituted sandwich-type polyoxometalates with a strong metal-C (imidazole) bond as anticancer agents' by Hongxia Zhao et al., Chem. Commun., 2019, 55, 1096-1099.

Transition metal substituted sandwich-type polyoxometalates with a strong metal-C (imidazole) bond as anticancer agents.

Two novel sandwich-type polyoxometalates {Na0.7M5.3(H2O)2(imi)2(Himi)(SbW9O33)2}6- (M = NiII (1), CoII (2), imi = imidazole) containing a strong M-Cimi bond were synthesized by a tetragonal cluster [Na2Sb8W36O132(H2O)4]22- {Sb8W36} precursor. Compound 1 was highly cytotoxic against gastric cancer cells by arresting the cell cycle in the S-phase and inducing cell apoptosis.

Synthesis, in vitro cytotoxicity, and structure-activity relationships (SAR) of multidentate oxidovanadium(iv) complexes as anticancer agents.

Multidentate oxidovanadium(iv) complexes with different geometric configurations [VO(ox)(bpy)(H2O)] 1, [VO(ox)(phen)(H2O)] 2, [VO(ida)(bpy)]·2H2O 3, (phen)[VO(ida)(phen)]·4H2O 4, and (Hphen)[VO(H2O)(nta)]·2H2O 5 [ox = oxalic acid, bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline, ida = iminodiacetic acid, nta = nitrilotriacetic acid] have been obtained from the reactions of oxidovanadium sulfate or vanadium pentoxide with oxalates, amino-polycarboxylates and N-heterocyclic ligands in neutral solution by the hydrothermal method, and have been fully characterized by elemental, thermogravimetric analyses and single crystal X-ray diffraction, as well as a wide range of spectroscopic techniques such as FT-IR, UV/Vis, NMR, ESI-MS. The anti-tumor properties of oxidovanadium compounds 1-5 were further evaluated in human HepG2 and SMMC-7721 hepatocellular carcinoma cell lines in vitro. The profiles of cytotoxicity, cell cycle distribution, as well as cell apoptosis upon test compound exposure, were determined by MTT and flow cytometry assays. Compound 2 exhibited a much higher anti-tumor activity than others. The IC50 values of 2 were 5.34 ± 0.034 µM and 29.07 ± 0.017 µM in SMMC-7721 and HepG2 cells after 48 h treatment, respectively. Furthermore, compound 2 could significantly arrest the cell cycle in the S and G2/M phases and further induce cell apoptosis in a dose-dependent manner. The structure-activity relationship (SAR) studies revealed that structural elements, for example, metal components, variations of coordination mode, labile water molecules, chelated ligands etc., probably exert an essential cooperative effect on the antitumor activity. In short, these findings not only provide an accessible model system to exploit V-based complexes as potential simple, safe and effective multifunctional antitumor agents, but also open up a rational approach to shed new light on the selection and optimization of ideal drug candidates.

3D ordered silver nanoshells silica photonic crystal beads for multiplex encoded SERS bioassay.

3D ordered silver nanoshells silica photonic crystal beads as a novel encoded surface enhanced Raman scattering substrate are proposed for the development of highly efficient multiplex bioassays.

Quantum-dot-tagged photonic crystal beads for multiplex detection of tumor markers.

Novel quantum-dot-tagged photonic crystal beads were fabricated for multiplex detection of tumor markers via self-assembly of quantum dot-embedded polystyrene nanospheres into photonic crystal beads through a microfluidic device.

Synthesis of the first amphiphilic pillar[6]arene and its enzyme-responsive self-assembly in water.

The first amphiphilic pillar[6]arene was successfully synthesized. It can complex with adenosine triphosphate to form vesicles in water. Moreover, these vesicles are efficiently responsive to phosphatase.

Water-soluble inclusion complex of fullerene with γ-cyclodextrin polymer for photodynamic therapy.

A stable aqueous inclusion complex of fullerene (C60) with macromolecules (C60 concentration as high as 3 × 10-4 mol L-1) was achieved by a one-step strategy using γ-cyclodextrin polymer (γ-CDP). The inclusion complex of C60 with γ-CDP (C60-γ-CDP) was characterized by ultraviolet-visible, Raman and 1H-NMR spectroscopies, powder X-ray diffraction analysis, and thermogravimetric analysis. The supramolecular interactions and the equilibrium constant for a 1 : 2 (C60 : CD unit in γ-CDP) complex of C60 with γ-CDP were studied. Under ultraviolet A (UVA) irradiation C60-γ-CDP in water could generate singlet oxygen, which was detected by electron paramagnetic resonance spectroscopy. We also evaluated the cytotoxicities of C60-γ-CDP, and investigated the phototoxicity of C60-γ-CDP and pristine C60 toward B16-F10 melanoma cells. The cell viability test showed that C60-γ-CDP had a significantly higher photodynamic ability than that of the pristine C60 under UVA irradiation. This work demonstrated both a CDP-functionalized strategy for enhancing the water-solubility and phototoxicity of fullerenes for applications in cancer photodynamic therapy, as well as remediating the negative biological effects of pristine fullerenes.

Electrogenerated trisbipyridyl Ru(II)-/nitrilotriacetic-polypyrene copolymer for the easy fabrication of label-free photoelectrochemical immunosensor and aptasensor: application to the determination of thrombin and anti-cholera toxin antibody.

A bifunctional copolymer was electrogenerated, which allows efficient bioreceptor immobilization and transduction of the biorecognition event. This copolymer was formed using pyrenebutyric acid Nα',Nα-bis(carboxymethyl)-L-lysine amide (NTA-pyrene) and [tris-(2,2'-bipyridine) (4,4'-bis(4-pyrenyl-1-ylbutyloxy)-2,2'-bipyridine] ruthenium(II) hexafluorophosphate (Ru(II)-pyrene) complex. The pyrene groups, present in both compounds, undergo oxidative electropolymerization on platinum electrodes. The resulting copolymer contains NTA moieties, which were used as a versatile immobilization system for biotin- and histidine-tagged biomolecules, while Ru(II)-pyrene was employed as a photoelectrochemical transducing molecule. The efficiency of this copolymer for biomolecule anchoring was investigated with biotin- and histidine- tagged glucose oxidases, biotin-tagged cholera toxin and a histidine-tagged thrombin aptamer. The constructed enzyme electrodes exhibited an amperometric response toward glucose at 0.6 V vs SCE, demonstrating the anchoring of this enzyme via two coordination systems. An immunosensor configuration based on the immobilization of biotin-tagged cholera toxin was applied to the detection of anti-cholera antibody while the aptasensor based on the immobilization of histidine-tagged thrombin aptamer was tested for thrombin determination. The biorecognition events were monitored via the evolution of the photocurrent intensity generated by the polymerized Ru(II)-pyrene in the presence of visible light and a sacrificial donor (ascorbate). The binding of the targets hinders the diffusion of the sacrificial donor, inducing thus a photocurrent decrease. The constructed immunosensor presents a specific label-free photoelectrochemical response to anti-cholera antibody without labeling step, the detection limit being 0.2 µg mL⁻¹. The label-free photoelectrochemical response of the aptasensor varies linearly with thrombin concentrations up to 10 pmol L⁻¹, the detection limit being 1×10⁻¹³ mol L⁻¹.

Tetra-kis(1H-imidazole-κN)(2-phenyl-propanedioato-κO,O)nickel(II).

In the title complex, [Ni(C(9)H(6)O(4))(C(3)H(4)N(2))(4)], the Ni(II) ion is O,O'-chelated by the phenyl-malonato ligand and coordinated by four imidazole ligands in a slightly distorted octa-hedral geometry. In the crystal structure, symmetry-related mol-ecules are linked by N-H⋯O hydrogen bonds, generating a three-dimensional network.

4-(4-Pyrid-yl)pyridinium 3-amino-5-carb-oxy-2,4,6-triiodo-benzoate-5-amino-2,4,6-triiodo-isophthalic acid (1/1).

In the title ammonium carboxyl-ate-carb-oxy-lic acid co-cystal, C(10)H(9)N(2) (+)·C(8)H(3)I(3)NO(4) (-.)C(8)H(4)I(3)NO(4), the carboxyl-ate anion and carb-oxy-lic acid mol-ecule are linked by O-H⋯O and N-H⋯O hydrogen bonds to form a chain running along the c axis of the monoclinic unit cell. The chains are linked by pyridinum and pyridine N-H⋯O hydrogen bonds, generating a layer motif. O-H⋯N and O-H⋯O hydrogen bonds are also observed.