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Composite electrolytes have been accepted as the most promising species for solid-state batteries, exhibiting the synergistic advantages of solid polymer electrolytes (SPEs) and solid ceramic electrolytes (SCEs). Unfortunately, the interrupted Li+ conduction across the SPE and SCE interface hinders the ionic conductivity improvement of composite electrolytes. In our study on a ceramic-rich composite electrolyte (CRCE) membrane composed of borate polyanion-based lithiated poly(vinyl formal) (LiPVFM) and Li1.3Al0.3Ti1.7(PO4)3 (LATP) particles, it is found that the strong interaction between the polyanions in LiPVFM and LATP particles results in a uniform distribution of ceramic particles at a high proportion of 50 wt % and good robustness of the electrolyte membrane with a Young's modulus of 9.20 GPa. More importantly, ab initio molecular dynamics simulation and experimental results demonstrate that Li+ conduction across the SPE and SCE interface is induced by the polyanion-based polymer due to its high lithium-ion transference number and similar Li+ diffusion coefficient with the SCE. Therefore, the unblocked Li+ conduction among ceramic particles dominates in the CRCE membrane with a high ionic conductivity of 6.60 × 10-4 S cm-1 at 25 °C, a lithium-ion transference number of 0.84, and a wide electrochemical stable window of 5.0 V (vs Li/Li+). Consequently, the high nickel ternary cathode LiNi0.8Mn0.1Co0.1O2-based batteries with CRCE deliver a high-rate capability of 135.08 mAh g-1 at 1.0 C and a prolonged cycle life of 100 cycles at 0.2 C between 3.0 and 4.3 V. The polyanion-induced Li+ conduction across the interface sheds new light on solving composite electrolyte problems for solid-state batteries.

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Li-rich antiperovskite (LiRAP) hydroxyhalides are emerging as attractive solid electrolyte (SEs) for all-solid-state Li metal batteries (ASSLMBs) due to their low melting point, low cost, and ease of scaling-up. The incorporation of rotational polyanions can reduce the activation energy and thus improve the Li ion conductivity of SEs. Herein, we propose a ternary rotational polyanion coupling strategy to fasten the Li ion conduction in tetrafluoroborate (BF4 -) ion doped LiRAP Li2OHCl. Assisted by first-principles calculation, powder X-ray diffraction, solid-state magnetic resonance and electrochemical impedance spectra, it is confirmed that Li ion transport in BF4 - ion doped Li2OHCl is strongly associated with the rotational coupling among OH-, BF4 - and Li2-O-H octahedrons, which enhances the Li ion conductivity for more than 1.8 times with the activation energy lowering 0.03 eV. This work provides a new perspective to design high-performance superionic conductors with multi-polyanions.

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All-solid-state sodium batteries are attracting intensive attention, and chloride-based solid electrolytes are promising candidates for use in such batteries because of their high chemical stability and low Young's modulus. Here, we report new superionic conductors based on polyanion-added chloride-based materials. Na0.67 Zr(SO4 )0.33 Cl4 showed a high ionic conductivity of 1.6 mS cm-1 at room temperature. X-ray diffraction analysis indicated that the highly conducting materials are mainly a mixture of an amorphous phase and Na2 ZrCl6 . The conductivity might be dominated by the electronegativity of the central atom of the polyanion. Electrochemical measurements reveal that Na0.67 Zr(SO4 )0.33 Cl4 is a sodium ionic conductor and is suitable for use as a solid electrolyte in all-solid-state sodium batteries.

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Hierarchical nucleation pathways are ubiquitous in the synthesis of minerals and materials. In the case of zeolites and metal-organic frameworks, pre-organized multi-ion "secondary building units" (SBUs) have been proposed as fundamental building blocks. However, detailing the progress of multi-step reaction mechanisms from monomeric species to stable crystals and defining the structures of the SBUs remains an unmet challenge. Combining in situ nuclear magnetic resonance, small-angle X-ray scattering, and atomic force microscopy, we show that crystallization of the framework silicate, cyclosilicate hydrate, occurs through an assembly of cubic octameric Q3 8 polyanions formed through cross-linking and polymerization of smaller silicate monomers and other oligomers. These Q3 8 are stabilized by hydrogen bonds with surrounding H2 O and tetramethylammonium ions (TMA+ ). When Q3 8 levels reach a threshold of ≈32 % of the total silicate species, nucleation occurs. Further growth proceeds through the incorporation of [(TMA)x (Q3 8 )⋅n H2 O](x-8) clathrate complexes into step edges on the crystals.

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In this review, we considered aspects related to the application of polyelectrolytes, primarily synthetic polyanions and polycations, to immobilize enzymes and regulate their properties. We mainly focused on the description of works in which polyelectrolytes were used to create complex and unusual systems (self-regulated enzyme-polyelectrolyte complexes, artificial chaperones, polyelectrolyte brushes, layer-by-layer immobilization and others). These works represent the field of "smart polymers", whilst the trivial use of charged polymers as carriers for adsorption or covalent immobilization of proteins is beyond the scope of this short review. In addition, we have included a section on the molecular modeling of interactions between proteins and polyelectrolytes, as modeling the binding of proteins with a strictly defined, and already known, spatial structure, to disordered polymeric molecules has its own unique characteristics.

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The development of large-scale energy storage systems (EESs) is pivotal for applying intermittent renewable energy sources such as solar energy and wind energy. Lithium-ion batteries with LiFePO4 cathode have been explored in the integrated wind and solar power EESs, due to their long cycle life, safety, and low cost of Fe. Considering the penurious reserve and regional distribution of lithium resources, the Fe-based sodium-ion battery cathodes with earth-abundant elements, environmental friendliness, and safety appear to be the better substitutes in impending grid-scale energy storage. Compared to the transition metal oxide and Prussian blue analogs, the Fe-based polyanionic oxide cathodes possess high thermal stability, ultra-long cycle life, and adjustable voltage, which is more commercially viable in the future. This review summarizes the research progress of single Fe-based polyanionic and mixed polyanionic oxide cathodes for the potential sodium-ion batteries EESs candidates. In detail, the synthesized method, crystal structure, electrochemical properties, bottlenecks, and optimization method of Fe-based polyanionic oxide cathodes are discussed systematically. The insights presented in this review may serve as a guideline for designing and optimizing Fe-based polyanionic oxide cathodes for coming commercial sodium-ion batteries EESs.

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The development of Mg-ion batteries is hindered by the lack of cathode materials that allow facile and reversible Mg2+ intercalation at high potential. Herein, the authors present a polyanion cathode material of K2 (VO)2 (HPO4 )2 (C2 O4 )⋅4.5H2 O (KVPCH) for Mg-ion batteries. The inductive effect of polyanions ensures the high redox potential of the vanadium centers. In addition, the material contains structural water located between the layers. It helps with Mg2+ desolvation at the electrode-electrolyte interface and facilitates its diffusion in the structure, as confirmed by experimental analysis and theoretical calculations. Thanks to those factors, the KVPCH electrode presents excellent Mg storage capability at room temperature. It delivers 121 mAh g-1 capacity at 1C with a high average discharge potential of 0.16 V versus Ag/Ag+ (3.2 V vs Mg/Mg2+ ). A capacity retention of 87% is realized after 1500 cycles at 5C. A rocking-chair Mg-ion full cell is also demonstrated with the KVPCH cathode and a MoOx anode, which achieves 46 mAh g-1 capacity (based on the total active material mass of two electrodes). This work would bring effective paths for the design of cathode materials for Mg-ion batteries.

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Sulfated polysaccharides and other polyanions have been promising candidates in antiviral research for decades. These substances gained attention as antivirals when they demonstrated a high inhibitory effect in vitro against human immunodeficiency virus (HIV) and other enveloped viruses. However, that initial interest was followed by wide skepticism when in vivo assays refuted the initial results. In this paper we review the use of sulfated polysaccharides, and other polyanions, in antiviral therapy, focusing on extracellular polymeric substances (EPSs). We maintain that, in spite of those early difficulties, the use of polyanions and, specifically, the use of EPSs, in antiviral therapy should be reconsidered. We base our claim in several points. First, early studies showed that the main disadvantage of sulfated polysaccharides and polyanions is their low bioavailability, but this difficulty can be overcome by the use of adequate administration strategies, such as nebulization of aerosols to gain access to respiratory airways. Second, several sulfated polysaccharides and EPSs have demonstrated to be non-toxic in animals. Finally, these macromolecules are non-specific and therefore they might be used against different variants or even different viruses.

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Inhibitors of viral cell entry based on poly(styrene sulfonate) and its core-shell nanoformulations based on gold nanoparticles are investigated against a panel of viruses, including clinical isolates of SARS-CoV-2. Macromolecular inhibitors are shown to exhibit the highly sought-after broad-spectrum antiviral activity, which covers most analyzed enveloped viruses and all of the variants of concern for SARS-CoV-2 tested. The inhibitory activity is quantified in vitro in appropriate cell culture models and for respiratory viral pathogens (respiratory syncytial virus and SARS-CoV-2) in mice. Results of this study comprise a significant step along the translational path of macromolecular inhibitors of virus cell entry, specifically against enveloped respiratory viruses.

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The multiple issues of unstable electrode/electrolyte interphases, sluggish reaction kinetics, and transition-metal (TM) dissolution have long greatly affected the rate and cycling performance of cathode materials for Na-ion batteries. Herein, a multifunctional protein-based binder, sericin protein/poly(acrylic acid) (SP/PAA), is developed, which shows intriguing physiochemical properties to address these issues. The highly hydrophilic nature and strong H-bond interaction between crosslinking SP and PAA leads to a uniform coating of the binder layer, which serves as an artificial interphase on the high-voltage Na4 Mn2 Fe(PO4 )2 P2 O7 cathode material (NMFPP). Through systematic experiments and theoretical calculations, it is shown that the SP/PAA binder is electrochemically stable at high voltages and possesses increased ionic conductivity due to the interaction between sericin and electrolyte anion ClO4 - , which can provide additional sodium-migration paths with greatly reduced energy barriers. Besides, the strong interaction force between the binder and the NMFPP can effectively protect the cathode from electrolyte corrosion, suppress Mn-dissolution, stabilize crystal structure, and ensure electrode integrity during cycling. Benefiting from these merits, the SP/PAA-based NMFPP electrode displays enhanced rate and cycling performance. Of note, the universality of the SP/PAA binder is further confirmed on Na3 V2 (PO4 )2 F3 . It is believed that the versatile protein-based binder is enlightening for the development of high-performance batteries.

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Alzheimer's disease (AD) is a multifactorial neurodegenerative disease characterized by progressive cognitive impairment, apathy, and neuropsychiatric disorders. Two main pathological hallmarks have been described: neurofibrillary tangles, consisting of tau oligomers (hyperphosphorylated tau) and Aß plaques. The influence of protein kinases and phosphatases on the hyperphosphorylation of tau is already known. Hyperphosphorylated tau undergoes conformational changes that promote its self-assembly. However, the process involving these mechanisms is yet to be elucidated. In vitro recombinant tau can be aggregated by the action of polyanions, such as heparin, arachidonic acid, and more recently, the action of polyphosphates. However, how that process occurs in vivo is yet to be understood. In this review, searching the most accurate and updated literature on the matter, we focus on the precise molecular events linking tau modifications, its misfolding and the initiation of its pathological self-assembly. Among these, we can identify challenges regarding tau phosphorylation, the link between tau heteroarylations and the onset of its self-assembly, as well as the possible metabolic pathways involving natural polyphosphates, that may play a role in tau self-assembly.

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This clinical review presents what is known about the antiviral features of humic substances (HS) to the benefit of the clinical healthcare provider using available data in humeomics, the study of the soil humeome. It provides the reader with a working framework of historical studies and includes clinically relevant data with the goal of providing a broad appreciation of the antiviral potential of humic substances while also preparing for a translational leap into the clinical application of humic acid.

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The production of stable and homogeneous batches during nanoparticle fabrication is challenging. Surface charging, as a stability determinant, was estimated for 3-aminopropyltriethoxysilane (APTES) coated pre-formed magnetite nanoparticles (MNPs). An important consideration for preparing stable and homogenous MNPs colloidal systems is the dispersion stage of pre-formed samples, which makes it feasible to increase the MNP reactive binding sites, to enhance functionality. The results gave evidence that the samples that had undergone stirring had a higher loading capacity towards polyanions, in terms of filler content, compared to the sonicated ones. These later results were likely due to the harsh effects of sonication (extremely high temperature and pressure in the cavities formed at the interfaces), which induced the destruction of the MNPs.

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Recent advances in high-resolution structural studies of protein amyloids have revealed parallel in-register cross-ß-sheets with periodic arrays of closely spaced identical residues. What do these structures tell us about the mechanisms of action of common amyloid-promoting factors, such as heparan sulfate (HS), nucleic acids, polyphosphates, anionic phospholipids, and acidic pH?

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While the ongoing COVID-19 pandemic affirms an urgent global need for effective vaccines as second and third infection waves are spreading worldwide and generating new mutant virus strains, it has also revealed the importance of mitigating the transmission of SARS-CoV-2 through the introduction of restrictive social practices. Here, it is demonstrated that an architecturally- and chemically-diverse family of nanostructured anionic polymers yield a rapid and continuous disinfecting alternative to inactivate coronaviruses and prevent their transmission from contact with contaminated surfaces. Operating on a dramatic pH-drop mechanism along the polymer/pathogen interface, polymers of this archetype inactivate the SARS-CoV-2 virus, as well as a human coronavirus surrogate (HCoV-229E), to the minimum detection limit within minutes. Application of these anionic polymers to frequently touched surfaces in medical, educational, and public-transportation facilities, or personal protection equipment, can provide rapid and repetitive protection without detrimental health or environmental complications.

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MIV molecular oxo-clusters (M=Zr, Hf, Ce, Th, U, Np, Pu) are prolific in bottoms-up material design, catalysis, and elucidating reaction pathways in nature and in synthesis. Here we introduce Ce70 , a wheel-shaped oxo-cluster, [CeIV 70 (OH)36 (O)64 (SO4 )60 (H2 O)10 ]4- . Ce70 crystallizes into intricate high pore volume frameworks with divalent transition metals and Ce-monomer linkers. Eight crystal-structures feature four framework types in which the Ce70 -rings are linked as propellers, in offset-stacks, in a tartan pattern, and as isolated rings. Small-angle X-ray scattering of Ce70 dissolved in butylamine, with and without added cations (CeIV , alkaline earths, MnII ), shows the metals' differentiating roles in ring linking, leading to supramolecular assemblies. The large acidic pores and abundant terminal sulfates provide ion-exchange behavior, demonstrated with UIV and NdIII . Frameworks featuring CeIII/IV -monomer linkers demonstrate both oxidation and reduction. This study opens the door to mixed-metal, highly porous framework catalysts, and new clusters for metal-organic framework design.

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We hypothesize that polycations, such as nuclear histones, released by neutrophils COVID-19 aggravate COVID-19 by multiple mechanisms: (A) Neutralization of the electrostatic repulsion between the virus particles and the cell membrane, thereby enhancing receptor-mediated entry. (B) Binding to the virus particles, thereby inducing opsonin-mediated endocytosis. (C) Adding to the cytotoxicity, in conjunction with oxidants, cytokines and other pro-inflammatory substances secreted by cells of the innate immunity system. These effects may be alleviated by the administration of negatively charged polyanions such as heparins and heparinoids.

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In order to prolong the release and reduce the toxicity of anticancer drug - doxorubicin (DOX), delivery systems (DS) using different polyanions have been developed. Structural (size, morphological stability) and functional (encapsulation efficiency, DOX release) characteristics of three types of DS are compared: CaCO3 porous vaterites doped with polyanions by co-precipitation and coating techniques, and DOX-polyanion conjugates. Using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), it was shown that the doping enhances the morphological stability of CaCO3-based DS during the DOC loading. Doping of CaCO3 cores by co-precipitation reduces its sizes (up to 1 µm) and DOX encapsulation efficiency. Polyanion-coated CaCO3 cores and polyanion drug conjugates show about 98 w/w% DOX encapsulation. For the first time, it was shown that the release of DOX from developed DS into human blood plasma is more intense (from 1.3 to 3.0 times for different DS) than into model tumour environment.

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The idea that amyloid fibrils and other types of protein aggregates are toxic for cells has been challenged by the discovery of a variety of functional aggregates. However, an identification of crucial differences between pathological and functional aggregation remains to be explored. Functional protein aggregation is often reversible by nature in order to respond properly to changing physiological conditions of the cell. In addition, increasing evidence indicates that fast fibril growth is a feature of functional amyloids, providing protection against the long-term existence of potentially toxic oligomeric intermediates. It is becoming clear that functional protein aggregation is a complexly organized process that can be mediated by a multitude of biomolecular factors. In this overview, we discuss the roles of diverse biomolecules, such as lipids/membranes, glycosaminoglycans, nucleic acids and metal ions, in regulating functional protein aggregation. Our studies on the protein GAPR-1 revealed that several of these factors influence the amyloidogenic properties of this protein. These observations suggest that GAPR-1, as well as the cysteine-rich secretory proteins, antigen 5 and pathogenesis-related proteins group 1 (CAP) superfamily of proteins that it belongs to, require the assembly into an amyloid state to exert several of their functions. A better understanding of functional aggregate formation may also help in the prevention and treatment of amyloid-related diseases.

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