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We present a simple approximation to estimate the largest charge that a given molecule can hold until fragmentation into smaller charged species becomes more energetically favorable. This approximation solely relies on the ionization potentials, electron affinities of the parent and fragment species, and also on the neutral parent's dissociation energy. By parameterizing these quantities, it is possible to obtain analytical phase diagrams of polycationic stability. We demonstrate the applicability of this approach by discussing the maximal charge dependence on the size of the molecular system. A numerical demonstration for linear polyenes, monocyclic annulenes, and helium clusters is provided. [ABSTRACT FROM AUTHOR]

This work focuses on the first use of ultrasonic phenol-ene coupling as a polymer analogous transformation. The ultrasonic reaction was introduced into chitin chemistry, resulting in the fast and convenient preparation of new water-soluble cationic chitin derivatives. Since water-soluble derivatives of fully deacetylated chitin are poorly described in the literature, the synthesis of each new type of these derivatives is a significant event in polysaccharide chemistry. Polycations, or cationic polymers, are of particular interest as antibacterial agents. Consequently, the resulting polymers were tested for their antibacterial activity and toxicity. We found that the highly substituted polymer of medium molecular weight exhibited the most pronounced in vitro antibacterial effect. We prepared nanoparticles using the ionic gelation technique. The most effective in vitro antibacterial chitin-based systems were tested in vivo in rats. These tests demonstrated outstanding antibacterial effects combined with an absence of toxicity. Additionally, we found that the resulting polymers, unlike their nanoparticle counterparts, also exhibited strong antioxidant effects. In summary, we demonstrated the effectiveness of ultrasound in polymer chemistry and highlighted the importance of the sonochemical approach in the chemical modification of polysaccharides. This approach enables the synthesis of derivatives with improved physicochemical and biological properties. [ABSTRACT FROM AUTHOR]

ESKAPE pathogens are a panel of most recalcitrant bacteria that could "escape" the treatment of antibiotics and exhibit high incidence of drug resistance. The emergence of multidrug-resistant (MDR) ESKAPE pathogens (particularly Gram-negative bacteria) accounts for high risk of mortality and increased resource utilization in health care. Worse still, there has been no new class of antibiotics approved for exterminating the Gram-negative bacteria for more than 50 years. Therefore, it is urgent to develop novel antibacterial agents with low resistance and potent killing efficacy against Gram-negative ESKAPE pathogens. Herein, we present a class of fluoropolymers by mimicking the amphiphilicity of cationic antimicrobial peptides. Our optimal fluoroamphiphilic polymer (PD45HF5) displayed selective antimicrobial ability for all MDR Gram-negative ESAKPE pathogens, low resistance, high in vitro cell selectivity, and in vivo curative efficacy. These findings implied great potential of fluoroamphiphilic cationic polymers as promising antibacterial agents against MDR Gram-negative ESKAPE bacteria and alleviating antibiotic resistance. [ABSTRACT FROM AUTHOR]

Hypervascularized glioblastoma is naturally sensitive to anti‐angiogenesis but suffers from low efficacy of transient vasculature normalization. In this study, a lipid‐polymer nanoparticle is synthesized to execute compartmentalized Cas9 and sgRNA delivery for a permanent vasculature editing strategy by knocking out the signal transducer and activator of transcription 3 (STAT3). The phenylboronic acid branched cationic polymer is designed to condense sgRNA electrostatically (inner compartment) and patch Cas9 coordinatively (outer compartment), followed by liposomal hybridization with angiopep‐2 decoration for blood–brain barrier (BBB) penetration. The lipid‐polymer nanoparticles can reach glioblastoma within 2 h post intravenous administration, and hypoxia in tumor cells triggers charge‐elimination and degradation of the cationic polymer for burst release of Cas9 and sgRNA, accompanied by instant Cas9 RNP assembly, yielding ≈50% STAT3 knockout. The downregulation of downstream vascular endothelial growth factor (VEGF) reprograms vasculature normalization to improve immune infiltration, collaborating with interleukin‐6 (IL‐6) and interleukin‐10 (IL‐10) reduction to develop anti‐glioblastoma responses. Collectively, the combinational assembly for compartmentalized Cas9/sgRNA delivery provides a potential solution in glioblastoma therapy. [ABSTRACT FROM AUTHOR]

The water extractability and acute aquatic toxicity of seven aliphatic diisocyanate-based prepolymer substances were investigated to determine if lesser reactivity of the aliphatic isocyanate groups, as well as increased ionization potential of the expected (aliphatic amine-terminated) polymeric hydrolysis products, would in- fluence their aquatic behavior compared to that of previously investigated aromatic diisocyanate-based prepolymers. At loading rates of 100 and 1,000 mg/L, only the substances having log Kow ≤9 exhibited more than 1% extractability in water, and a maximum of 66% water extractability was determined for a prepolymer having log Kow = 2.2. For the more hydrophobic prepolymer substances (log Kow values from 18-37), water extractability was negligible. High-resolution mass spectrometric analyses were performed on the water-accommodated fractions (WAF) of the prepolymers, which indicated the occurrence of primary aliphatic amine-terminated polymer species having backbones and functional group equivalent weights aligned to those of the parent prepolymers. Measurements of reduced surface tension and presence of suspended micelles in the WAFs further supported the occurrence of these surface-active cationic polymer species as hydrolysis products of the prepolymers. Despite these characteristics, the water-extractable hydrolysis products were practically nontoxic to Daphnia magna. All of the substances tested exhibited 48-h EL50 values of >1,000 mg/L, with one exception of EL50 = 157 mg/L. The results from this investigation support a grouping of the aliphatic diisocyanatebased prepolymers as a class of water-reactive polymer substances having predictable aquatic exposure and a uniformly low hazard potential, consistent with that previously demonstrated for the aromatic diisocyanatebased prepolymers. [ABSTRACT FROM AUTHOR]

The physical interactions between anionic and cationic monomers and the layered silicate clay mineral Laponite (XLG) have received great attention because of their potential for a variety of applications such as strain sensitive sensors, wearable electronics, drug delivery systems, and tissue engineering applications. A detailed investigation of the interaction between XLG and charged monomers is presented in this article. The study includes the observation of the changes in the viscosity of the solutions and the mechanical performance of the gels at various concentrations by adding XLG to the ionic monomer solution. The ionic interactions between XLG and the charged monomers, driven by electrostatic forces, play a crucial role in gelation and formation of a three-dimensional network, giving the structure strain rate sensitivity. In this way, the addition of XLG nanoparticles not only improves the mechanical properties of the gels, but also gives us information about the microstructure of the mechanical properties that change depending on the strain rate. [ABSTRACT FROM AUTHOR]

The thermosensitive ceramics of negative temperature coefficient (NTC), SrCo 1- x Ru x O 3 (0 ≤ x ≤ 0.8), were synthesized using the solid-phase method. The research systematically explored the phase structure, microstructure, elemental chemical states, electrical properties, and aging performance. X-ray diffraction (XRD) data indicates that with the increase of Ru content, the lattice parameter increases. Scanning electron microscopy (SEM) images reveal a dense and uniform microstructure. X-ray photoelectron spectroscopy (XPS) data indicates the presence of Co2+/Co3+ and Ru4+/Ru5+ ion pairs. Resistive temperature data indicates its potential use as a low-temperature thermosensitive resistance material in the range of 2–300 K. Fitting the resistance-temperature curve using the thermally activated band conduction model and Mott's 3D variable range hopping model. Proposed the Ru–O2--Co hopping model, elucidating the hole hopping transport mechanism in NTC ceramics. Impedance spectroscopy analysis indicates that grain boundary resistance dominates the overall resistance of the sample. After aging at 77 K for 864 h, the maximum aging drift rate of the ceramic material is 1.55 %. Proposed a novel cationic vacancy diffusion model to explain aging phenomena, offering a new perspective for designing high-stability low-temperature NTC thermistors. [ABSTRACT FROM AUTHOR]

Cationic polymers have great potential for cancer therapy due to their unique interactions with cancer cells. However, their clinical application remains limited by their high toxicity. Here we show a cell membrane-targeting cationic polymer with antineoplastic activity (Pmt) and a second near-infrared (NIR-II) fluorescent biodegradable polymer with photosensitizer Bodipy units and reactive oxygen species (ROS) responsive thioketal bonds (PBodipy). Subsequently, these two polymers can self-assemble into antineoplastic nanoparticles (denoted mt-NPBodipy) which could further accumulate at the tumor and destroy cell membranes through electrostatic interactions, resulting in cell membrane destabilization. Meanwhile, the photosensitizer Bodipy produces ROS to induce damage to cell membranes, proteins, and DNAs to kill cancer cells concertedly, finally resulting in cell membrane lysis and cancer cell death. This work highlights the use of near-infrared light to spatially and temporarily control cationic polymers for photodynamic therapy, photo-immunotherapy, and NIR-II fluorescence for bio-imaging. The application of synthetic polymeric nanoparticles for cancer therapy is limited by its biosafety and targeting ability. Here the authors report cationic nanoparticles that anchor and destabilize cancer cell membranes upon NIR-II irradiation for photo-immunotherapy and imaging. [ABSTRACT FROM AUTHOR]

Metabolic acidosis‐induced kidney injury (MAKI) is asymptomatic and lack of clinical biomarkers in early stage, but rapidly progresses to severe renal fibrosis and ultimately results in end‐stage kidney failure. Therefore, developing rapid and noninvasive strategies direct responsive to renal tubular acidic microenvironment rather than delayed biomarkers are essential for timely renoprotective interventions. Herein, we develop pH‐responsive luminescent gold nanoparticles (p‐AuNPs) in the second near‐infrared emission co‐coated with 2,3‐dimethylaleic anhydride conjugated β‐mercaptoethylamine and cationic 2‐diethylaminoethanethiol hydrochloride, which showed sensitive pH‐induced charge reversal and intrarenal self‐assembly for highly sensitive and long‐time (~24 h) imaging of different stages of MAKI. By integrating advantages of pH‐induced intrarenal self‐assembly and enhanced interactions between pH‐triggered positively charged p‐AuNPs and renal tubular cells, the early‐ and late‐stage MAKI could be differentiated rapidly within 10 min post‐injection (p.i.) with contrast index (CI) of 3.5 and 4.3, respectively. The corresponding maximum CI could reach 5.1 and 9.2 at 12 h p.i. respectively. Furthermore, p‐AuNPs were demonstrated to effectively real‐time monitor progressive recovery of kidney injury in MAKI mice after therapy, and also exhibit outstanding capabilities for drug screening. This pH‐responsive strategy showed great promise for feedback on kidney dysfunction progression, opening new possibilities for early‐stage diagnosis of pH‐related diseases. [ABSTRACT FROM AUTHOR]

This document is a compilation of research articles on the progress and development of polyurethane materials and composites. The articles cover a wide range of topics, including the synthesis and modification of polyurethane materials, the use of lignin as a raw material for polyurethane adhesives, the preparation of waterborne polyurethane coatings using castor oil, and the enhancement of fiber-matrix interface in polymer composites using graphene nanosheets. The research presented in this document provides valuable insights and references for researchers working with polyurethane materials. [Extracted from the article]

The rewritable wearables based on photochromism have emerged as attractive candidates in inkless printing applications. Among various photochromic materials, polyoxometalates have great potential for rewritable wearables, with major advantages in fast response upon UV irradiation, long‐term photochemical stability, and excellent fatigue resistance. However, the development of rewritable wearables based on polyoxometalates is limited by low combining fastness, weak stability, and poor scalability. Here, a scalable strategy is reported to fabricate an ideal rewritable wearable based on fundamental charge balance mechanism. The pristine cotton substrate is grafted by cationic polymer brushes to incorporate photochromic phosphomolybdic acid (PMoA) anions through electrostatic attraction, and then the cationic surfactants with alkyl chains are introduced to encapsulate the PMoA anions to achieve charge balance subsequently. The resultant rewritable wearables display the long‐awaited properties, such as high color contrast, favorable reversibility (>10 cycles), long color retention (>15 days) and high stability against detergent and sweat (pH 6.5–8.0) during repeated washing (50 cycles) and wearing. As a demonstration, a rewritable T‐shirt is scalably fabricated, and excellent antibacterial activity and biocompatibility are demonstrated as well, which is expected to be a sustainable solution for regular fabric printing in household products and public display. [ABSTRACT FROM AUTHOR]

A self‐assembled “caging” strategy is presented for the safe delivery of potent cationic antimicrobials that suffer from non‐specific toxicity for the effective treatment of in vivo systemic bacterial infection. The key development here is a new block copolymer consisting of a poly(ethylene glycol) (PEG) stealth block and an anionic and lipase‐degradable block of poly(ɛ‐caprolactone) (PCL) and phosphonic acid‐bearing methacrylate copolymer, synthesized by hybrid copolymerization of methacrylate and cyclic esters. The anionic blocks electrostatically interact with cationic antimicrobials to form neutrally charged polyion complexes with the PEG blocks on the surface. The PCL component imparts the nanocomplex with biodegradability by bacterial secretory lipase. In the proof‐of‐concept study, cationic polyimidazolium that shows excellent antibacterial activity but severe toxicity is packaged by the block copolymer into nanocomplexes, which are stable in complex environments of high salt and protein concentrations and released the antimicrobials upon degradation of the copolymer by bacteria‐secreted lipase. The “caging” formulation of polyimidazolium eliminated its toxicity and led to highly effective bactericidal performance comparable to free polyimidazolium. This caging strategy does not require sophisticated chemical modification of cationic antimicrobials, offering a broadly applicable formulation strategy to overcome their common toxicity issue that has become a primary translational barrier. [ABSTRACT FROM AUTHOR]

Anti-angiogenesis has emerged a promising strategy against colorectal cancer (CRC). However, the efficacy of anti-angiogenic therapy is greatly compromised by the up-regulated autophagy levels resulting from the evolutionary resistance mechanism and the presence of Fusobacterium nucleatum (F. nucleatum) in CRC. Herein, we report a cationic polymer capable of blocking autophagic flux to deliver plasmid DNA (pDNA) encoding soluble FMS-like tyrosine kinase-1 (sFlt-1) for enhanced anti-angiogenic therapy against F. nucleatum -associated CRC. The autophagy-inhibiting cationic polymer, referred to as PNHCQ, is synthesized by conjugating hydroxychloroquine (HCQ) into 3,3′-diaminodipropylamine-pendant poly(β-benzyl-L-aspartate) (PAsp(Nors)), which can be assembled and electrostatically interacted with sFlt-1 plasmid to form PNHCQ/sFlt-1 polyplexes. Hydrophobic HCQ modification not only boosts transfection efficiency but confers autophagy inhibition activity to the polymer. Hyaluronic acid (HA) coating is further introduced to afford PNHCQ/sFlt-1@HA for improved tumor targeting without compromising on transfection. Consequently, PNHCQ/sFlt-1@HA demonstrates significant anti-tumor efficacy in F. nucleatum -colocalized HT29 mouse xenograft model by simultaneously exerting anti-angiogenic effects through sFlt-1 expression and down-regulating autophagy levels exacerbated by F. nucleatum challenge. The combination of anti-angiogenic gene delivery and overall autophagy blockade effectively sensitizes CRC tumors to anti-angiogenesis, providing an innovative approach for enhanced anti-angiogenic therapy against F. nucleatum -resident CRC. Up-regulated autophagy level within tumors is considered responsible for the impaired efficacy of clinic antiangiogenic therapy against CRC colonized with pathogenic F. nucleatum. To tackle this problem, an autophagy-inhibiting cationic polymer is developed to enable efficient intracellular delivery of plasmid DNA encoding soluble FMS-like tyrosine kinase-1 (sFlt-1) and enhance anti-angiogenic therapy against F. nucleatum -associated CRC. HA coating that can be degraded by tumor-enriching hyaluronidase is further introduced for improved tumor targeting without compromising transfection efficiency. The well-orchestrated polyplexes achieve considerable tumor accumulation, efficient in vivo transfection, and effectively reinforce the sensitivity of CRC to the sFlt-1-derived anti-angiogenic effects by significantly blocking overall autophagy flux exacerbated by F. nucleatum challenge, thus harvesting robust antitumor outcomes against F. nucleatum -resident CRC. [Display omitted] [ABSTRACT FROM AUTHOR]

Many chemicals such as sodium chloride, sodium carbonate, synthetic dyes, oxidants, mordanting and softening agents used in clothing manufacture play a significant role in the pollution of global water resources. In view of cleaner technology, this article reviewed the effect of plasma pre-treatment on the dyeability of cotton fabric using a cleaner salt-free process. Greige cotton fabric was treated with diffuse coplanar surface barrier discharge (DCSBD) in air or nitrogen prior to the dyeing process. Three textile dyes are used in this work, reactive orange 16, direct red 81 and natural dye Acacia catechu (L.f.) Willd. Chitosan (CS) and quaternized poly[bis(2-chloroethyl) ether-alt-1,3-bis[3-(dimethylamino)propyl]urea (PQ-2) were used as cationic polymers to substitute the salt. The effect of the different treatments on the properties of the textile samples and the dyeing process was evaluated using scanning electon microscopy (SEM), ATR-FTIR, tearing strength and colorimetric measurements. The levelness and fastness properties of the obtained cotton samples were also assessed. The treated samples showed interesting colorimetric values proving the enhancement of the dye uptake without the involvement of salt or harmful additives and exhibited significant antibacterial activity. [ABSTRACT FROM AUTHOR]

The drug fenoprofen (FN) is available in two forms, R‐ and S‐enantiomers, which need to be separated for optimal therapeutic use. A novel poly(acrylonitrile‐co‐divinylbenzene) (PNB)‐based polymer sorbent designed specifically for S‐fenoprofen (S‐FN) enantioseparation was synthesized. This process began with creating low cross‐linked PNB microparticles through suspension polymerization. Next, hydrazine was introduced to react with the prevalent nitrile groups. The produced cationic hydrazidine‐functionalized polymer particles (HYD‐P) were then combined with anionic S‐FN. The imprinting of S‐FN was achieved by further cross‐linking with glutaraldehyde, which interacted with the NH2 groups. Subsequent acidic elution released the S‐FN enantiomers, leaving behind their specific receptor‐like cavities in the imprinted polymer particles (S‐FN‐P). The properties of the resulting polymers were analyzed using Fourier‐transform infrared (FTIR), 13C NMR, and x‐ray diffraction. Scanning electron microscopy was used to examine the surface structures of the sorbents. Under optimal conditions at pH 7, the sorbent showed an adsorption capacity of 240 mg/g for S‐FN. The chiral separation of the FN racemate achieved high enantiomeric excess (ee) levels, with 96% for R‐FN during loading and 94% for S‐FN during recovery. [ABSTRACT FROM AUTHOR]

Herein, conductive and stable partially fluorinated multi-cationic alkaline membrane (AM) has been reported by macromolecular modification of poly (vinylidene fluoride) (PVDF) and chemical grafting of vinyl benzyl chloride (VBC). Quaternization was achieved using different amines, to control the concentration of quaternary ammonium (QA) groups. Different multi-cationic AMs were analysed by their structural (1H NMR and FT-IR) and morphological properties, ion-exchange capacity (IEC), water uptake (WU), alkaline conductivity (κ m ), and stabilities (mechanical, chemical, and thermal). Due to presence of multi cationic groups and thus steric hindrance, reported membranes were robust in alkaline medium. Single-cell anion exchange membrane fuel cell (AMFC) assembled with Tri-amino-VBC-g-PVDF membrane, exhibited relatively high performance (open circuit voltage (OCV): 1.03 V, peak power density: 244.0 mW cm−2 at 400.0 mA cm−2), in compare with other AMs reported in the literature. It was observed that AMFC performance was strongly depends on cationic group density, and present study explored the utilization possibility of partially fluorinated polymer matrix with multi-cationic groups for long lifetime during AMFC application. [Display omitted] • High performance partially fluorinated multi-cationic alkaline membrane. • Alkaline membrane robust for Hofmann β -elimination and SN 2 reactions. • 96.34% remained conductivity after alkali treatment at 80 °C for 768 h. • 244.0 mW cm−2 maximum power density at 400.0 mA cm−2. [ABSTRACT FROM AUTHOR]

As a critical radioactive anionic contaminant, traditional adsorbents primarily remove iodate (IO3−) through ion exchange or hard acid‐hard base interactions, but suffer from limited affinity and capacity. Herein, employing the synergistic effect of ion exchange and redox, we successfully synthesized a redox‐active cationic polymer network (SCU‐CPN‐6, [C9H10O2N5 ⋅ Cl]n) by merging guanidino groups with ion‐exchange capability and phenolic groups with redox ability via a Schiff base reaction. SCU‐CPN‐6 exhibits a groundbreaking adsorption capacity of 896 mg/g for IO3−. The inferior adsorption capacities of polymeric networks containing only redox (~0 mg/g) or ion exchange (232 mg/g) fragments underscore the synergistic "1+1>2" effect of the two mechanisms. Besides, SCU‐CPN‐6 shows excellent uptake selectivity for IO3− in the presence of high concentrations of SO42−, Cl−, and NO3−. Meanwhile, a high distribution coefficient indicates its exemplary deep‐removal performance for low IO3− concentration. The synergic strategy not only presents a breakthrough solution for the efficient removal of IO3− but also establishes a promising avenue for the design of advanced adsorbents for diverse applications. [ABSTRACT FROM AUTHOR]

The development of cationic polymers as alternative materials to antibiotics necessitates addressing the challenge of balancing their antimicrobial activity and toxicity. Here we propose a precise switching strategy inspired by biomimetic voltage-gated ion channels, enabling controlled activation and inhibition of cationic antimicrobial functions through protein conformational transitions in diverse physiological environments. Following thermodynamic studies on the specific recognition between mannose end groups on polycations and concanavalin A (ConA), we synthesized a type of ConA-polycation nanoparticle. The nanoparticle was inhibited under neutral conditions, with cationic moieties shielded by ConA's β -sheet. This shielding suppresses their antimicrobial activity, thereby ensuring satisfactory biocompatibility. In mildly acidic environments, however, the transition of a portion of ConA to an α -helix conformation exposed cations at the particle periphery, activating antibacterial functionality. Compared to inhibited nanoparticles, those in the activated state exhibited a 32–256 times reduction in the minimum bactericidal concentration against bacteria and fungi (2–16 µg/mL). In a murine acute pulmonary infection model, intravenous administration of inhibited nanoparticles effectively reduced bacterial counts by 4-log within 12 h. The biomimetic design, regulating cationic antimicrobial functionality through the alteration in protein secondary structure, significantly retards bacterial resistance development, holding great promise for intelligent antimicrobial materials. Cationic antimicrobial polymers exhibit advantages distinct from antibiotics due to their lower propensity for resistance development. However, the presence of cationic moieties also poses a threat to healthy cells and tissues, significantly constraining their potential for clinical applications. To address this challenge, we propose a biomimetic strategy that mimics voltage-gated ion channels to activate the antimicrobial functionality of cations selectively in bacterial environments through the conformational transitions of proteins between β –sheets and α –helices. In healthy tissues, the antimicrobial functionality is inhibited, ensuring satisfactory biocompatibility. Antimicrobial cationic materials capable of intelligent switching between an activated state and an inhibited state in response to environmental changes offer an effective strategy to prevent the development of resistance and mitigate potential side effects. [Display omitted] [ABSTRACT FROM AUTHOR]

As a good alternative to natural fibers and petroleum-derived fibers, Lyocell fibers draw increasing interests owing to its advantages of sustainable forest source, low carbon emission, high strength and comfort. However, Lyocell exhibits significant fibrillation behavior under friction, which seriously reduce product quality and limit its further development. Herein, dual crosslinking networks were innovatively constructed in Lyocell cellulose structure to enhance the interaction of cellulose macromolecular chains. Bifunctional reactive dyes were loaded in the inner part of Lyocell fiber to form a primary crosslinking network. Then, the cellulose interaction in Lyocell skin layer was further enhanced after the coating by cationic waterborne polyurethane. The mechanism was determined and results showed that durable dual crosslinking networks were formed in Lyocell cellulose structure. From scanning electron microscope (SEM) observation, fibrillation behavior of Lyocell fibers was effectively prevented by dual crosslinking networks. Meanwhile, the durability was evaluated, showing that the treated fabric maintained good anti-fibrillation performance after washing for 50 times. Furthermore, the interaction of dyes and fibers was also enhanced by the cationic polymer via electrostatic attraction force, realizing high dye utilization efficiency. Therefore, the method exhibits great potential in promoting the application of Lyocell fibers in greener textile. [ABSTRACT FROM AUTHOR]

High dielectric biobased composites of TEMPO-oxidized cellulose nanofibers (TOCNFs) reinforced with cationic modified barium titanate (BTO) nanoparticles were fabricated in this work. In order to greatly eliminate the agglomeration of the nanofiller and improve the dielectric properties of the resulting film, the modification of BTO was achieved via the cationization with an etherifying agent on the basis of cladding polydopamine around BTO. The results showed that the modified BTO nanofiller had a good interfacial compatibility and dispersion in the TOCNF matrix due to the ionic and hydrogen bonds formed between the cationic modified BTO and anionic TOCNFs. Meanwhile, the modified BTO reinforced composites exhibited better dielectric properties. Especially, the composite film with 40 wt% modified BTO exhibited an ultrahigh dielectric constant of 116.2 (at 1 kHz) and a breakdown strength of 57.7 kV/mm, which was 696% and 51.4% respectively higher than that of pure TOCNF film. It was noticed that the hydrophobicity of the composite films was also slightly improved without sacrificing its mechanical strength. [ABSTRACT FROM AUTHOR]

Handwashing represents an important personal hygiene measure for preventing infection. Herein, we report the persistence of antibacterial and antiviral effects after handwashing with fatty acid salt-based hand soap. To this end, we developed a new in vitro test method to measure persistence, utilizing coacervation formed by anionic surfactants and cationic polymers to retain highly effective soap components against each bacterium and virus on the skin. Coacervation with fatty acid salts and poly diallyldimethylammonium chloride (PDADMAC) as a cationic polymer allowed the persistence of antibacterial and antiviral effects against E. coli, S. aureus, and influenza virus even 4 h after handwashing. Furthermore, we confirmed an increase in the number of residual components effective against each bacterium and virus on the skin. In summary, the current findings describe an effective approach for enhancing the protective effects of handwashing. [ABSTRACT FROM AUTHOR]

The widespread of drug‐resistant genes has greatly exacerbated the difficulty for the effectively tre atment of diseases associated with bacterial infections. The ineffectiveness of antibiotics poses great challenges to the development of new antimicrobial agents, especially those does not cause bacterial resistance. Herein, a cation porous organic polymer (CPOP) denoted as BDPP, was facilely prepared via the Alder‐Longo method skipping the tedious porphyrin‐bearing monomer synthesis procedure. The repeated porphyrin units endowed excellent photoactivity with the porous skeletons, and the inherent cations significantly improved the binding ability of BDPP with the bacterial cell membrane. As a result, the as‐synthesized POPs could be used as a physical broad spectrum sterilization agent, amalgamating the cation and photothermal therapy to exert synergistic amplified antibacterial effects. In vivo assay demonstrated BDPP with good biocompatibility, could also significantly promote the healing of wounds with bacteria‐infection. This work paves a facile way for the rational construction of material‐based antibacterial agent for the bacteria inactivation. [ABSTRACT FROM AUTHOR]

Copper‐free synthesis of cationic glycidyl triazolyl polymers (GTPs) is achieved through a thermal azide‐alkyne cycloaddition reaction between glycidyl azide polymer and propiolic acid, followed by decarboxylation and quaternization of the triazole unit. For synthesizing nonfunctionalized GTP (GTP‐H), a microwave‐assisted method enhances the decarboxylation reaction of carboxy‐functionalized GTP (GTP‐COOH). Three variants of cationic GTPs with different N‐substituents [N‐ethyl, N‐butyl, and N‐tri(ethylene glycol) monomethyl ether (EG3)] are synthesized. The molecular weight of GTP‐H is determined via size exclusion chromatography. Thermal properties of all GTPs are characterized using differential scanning calorimetry and thermogravimetric analysis. The ionic conductivities of these cationic GTPs are assessed by impedance measurements. The conducting ion concentration and mobility are calculated based on the electrode polarization model. Among three cationic GTPs, the GTP with the N‐EG3 substituent exhibits the highest ionic conductivity, reaching 6.8 × 10−6 S cm−1 at 25 °C under dry conditions. When compared to previously reported reference polymers, the reduction of steric crowding around the triazolium unit is considered to be a key factor in enhancing ionic conductivity. [ABSTRACT FROM AUTHOR]

The escalating spread of drug‐resistant bacteria and viruses is a grave concern for global health. Nucleic acids dominate the drug‐resistance and transmission of pathogenic microbes. Here, imidazolium‐type poly(ionic liquid)/porphyrin (PIL‐P) based electrospun nanofibrous membrane and its cerium (IV) ion complex (PIL‐P‐Ce) are developed. The obtained PIL‐P‐Ce membrane exhibits high and stable efficiency in eradicating various microorganisms (bacteria, fungi, and viruses) and decomposing microbial antibiotic resistance genes and viral nucleic acids under light. The nuclease‐mimetic and photocatalytic mechanisms of the PIL‐P‐Ce are elucidated. Co‐infection wound models in mice with methicillin‐resistant S. aureus and hepatitis B virus demonstrate that PIL‐P‐Ce integrate the triple effects of cationic polymer, photocatalysis, and nuclease‐mimetic activities. As revealed by proteomic analysis, PIL‐P‐Ce shows minimal phototoxicity to normal tissues. Hence, PIL‐P‐Ce has potential as a "green" wound dressing to curb the spread of drug‐resistant bacteria and viruses in clinical settings. [ABSTRACT FROM AUTHOR]

We formed core–shell‐like polyelectrolyte complexes (PECs) from an anionic bottlebrush polymer with poly (acrylic acid) side chains with a cationic linear poly (allylamine hydrochloride). By varying the pH, the number of side chains of the polyanionic BB polymers (Nbb), the charge density of the polyelectrolytes, and the salt concentration, the phase separation behavior and salt resistance of the complexes could be tuned by the conformation of the BBs. By combining the linear/bottlebrush polyelectrolyte complexation with all‐liquid 3D printing, flow‐through tubular constructs were produced that showed selective transport across the PEC membrane comprising the walls of the tubules. These tubular constructs afford a new platform for flow‐through delivery systems. [ABSTRACT FROM AUTHOR]

Perfluorosulfonated anionic ionomers are known for their robust ion conductivity and chemical and mechanical stability. However, the structure and transport property degradation of perfluorinated cationic polymers (PfCPs) are not well understood. Herein, we propose an ion-exchange strategy to identify the structural degradation, ion transport mechanisms, and architectural reformation of PfCPs. Particularly, we demonstrate that the utility of a –SO2–N+ strategy employing the Menshutkin reaction cannot yield reliable PfCPs and anion-exchange membranes, but can yield an unreliable zwitterionic intermediate (cations–anions molar ratio is approximately 7.6%). Moreover, the degradation products were efficiently reformed as proton exchange membranes (PEMs), and the as-reformed PEMs achieved an ion-exchange capacity (IEC) value (0.89 mmol g−1), meanwhile retaining more than 94.7% of their initial capacity. Furthermore, the fuel cell assembled with reformed PEMs displayed a power density of 0.91 Wcm−2 at 2.32 A cm−2, which was 90.1% of that of the robust perfluorosulfonic acid PEMs. Our combined findings shed some fresh light on the state of understanding of the structure–property relationship in PfCPs. [ABSTRACT FROM AUTHOR]

Functional polymers play an important role in various biomedical applications. From many choices, poly(2-isopropenyl-2-oxazoline) (PIPOx) represents a promising reactive polymer with great potential in various biomedical applications. PIPOx, with pendant reactive 2-oxazoline groups, can be readily prepared in a controllable manner via several controlled/living polymerization methods, such as living anionic polymerization, atom transfer radical polymerization (ATRP), reversible addition–fragmentation transfer (RAFT) or rare earth metal-mediated group transfer polymerization. The reactivity of pendant 2-oxazoline allows selective reactions with thiol and carboxylic group-containing compounds without the presence of any catalyst. Moreover, PIPOx has been demonstrated to be a non-cytotoxic polymer with immunomodulative properties. Post-polymerization functionalization of PIPOx has been used for the preparation of thermosensitive or cationic polymers, drug conjugates, hydrogels, brush-like materials, and polymer coatings available for drug and gene delivery, tissue engineering, blood-like materials, antimicrobial materials, and many others. This mini-review covers new achievements in PIPOx synthesis, reactivity, and use in biomedical applications. [ABSTRACT FROM AUTHOR]

As increasing fiber hydrophobicity can significantly improve the paper dewatering process, we found that replacing SBKP and HBKP with 0.5% superhydrophobic CPGMA can significantly improve the dewatering of paper sheets. Therefore, it can be concluded that if CPGMA has little effect on paper properties, it will have potential industrial value in the papermaking industry. Consequently, it is necessary to further study the effect of the CPGMAs@CPAM/SiO2/APAM system on paper properties. To evaluate the application potential of the system in the papermaking industry, we investigated the effects of CPGMAs, which replaced the fibers in the stocks, on the paper properties in the CPAM/SiO2/APAM system. The findings demonstrate that as the CPGMA replacement increased, the paper's tensile strength, bursting strength, tear resistance, and folding endurance all declined. The trend can be segmented into two phases: a rapid decrease for substitution amounts below 0.5% and a gradual decline for substitution amounts exceeding 0.5%. When replaced with a small amount of CPGMAs, there was a negligible effect on these properties. Second, the paper air permeability increased with the CPGMA substitution amount in the stock. Furthermore, the trend of paper air permeability can be divided into two stages—a rapid stage with a substitution amount of <0.5% and a slow stage with a substitution amount of >0.5%. A small amount of CPGMAs could distinctly improve the paper's air permeability. Third, CPGMAs, which replaced fibers in the stock, minutely affected the paper formation. A small amount of CPGMAs substantially boosted the efficacy of the process of paper manufacture and certain characteristics of the paper, and it had a negligible impact on the strength of paper. The CPGMAs@CPAM/SiO2/APAM technology has the potential to improve the retention and filtration performance of CPAM/SiO2/APAM. [ABSTRACT FROM AUTHOR]

Background: The therapeutic resistance to ionizing radiation (IR) and angiogenesis inhibitors is a great challenge for clinicians in the treatment of glioblastoma, which is associated with Hepatocyte growth factor (HGF)/MET, VEGF/VEGFR signaling pathway, and the crosstalk between them. In this study, we developed a novel recombinant fusion protein, rE27HGFK1, via HGFK1 tandem with 27 N-terminal residues of Endostatin (E27) and produced a polymeric nanoparticle formed by the co-polymer of PEGylated H1 cationic polymer (PH1) with a plasmid encoding the secreted rE27HGFK1 protein (PH1/pE27HGFK1). We further investigated the anti-tumor effects of rE27HGFK1 and PH1/pE27HGFK1 nanoparticles both in vivo and in vitro. Methods: We expressed and purified the rE27HGFK1 protein via E. coli. Then, we performed cellular experiments to determine the antitumoral effects and IR radio-sensitivities of the rE27HGFK1 protein in vitro. Finally, we performed animal studies to determine the tumor-targeted abilities and antitumoral activities of the polymeric nanoparticles, PH1/pE27HGFK1, in an orthotopic U118-Luc-bearing xenografted mouse model. Results: We showed that rE27HGFK1 inhibited the proliferation and the angiogenesis and enhanced the senescence and radiosensitivity of GBM via both MET and VEFGR2 signaling mediated-p16 over-expression and the down-regulation of cyclin D1-CDK4-Rb axis activities in vitro. Next, we displayed that systemic administration of the PEGylated H1 cationic polymer (PH1) effectively delivered the reporter genes to the brain tumor of an orthotopic U118-bearing xenografted mouse model. Finally, we showed that PH1/pE27HGFK1 significantly produced antitumor effects with radiosensitivity in the orthotopic U118-Luc-bearing xenografted Blab/c mouse model through inhibiting angiogenesis and tumor cell proliferation, as well as inducing the necrosis of tumor cells in vivo. Conclusions: The PH1/pE27HGFK1 nano-drug combined with radiotherapy can be used as a potentially effective therapeutic strategy for Glioblastoma multiforme. [ABSTRACT FROM AUTHOR]

Vinylene‐linked two‐dimensional polymers (V‐2DPs) and their layer‐stacked covalent organic frameworks (V‐2D COFs) featuring high in‐plane π‐conjugation and robust frameworks have emerged as promising candidates for energy‐related applications. However, current synthetic approaches are restricted to producing V‐2D COF powders that lack processability, impeding their integration into devices, particularly within membrane technologies reliant upon thin films. Herein, we report the novel on‐water surface synthesis of vinylene‐linked cationic 2DPs films (V‐C2DP‐1 and V‐C2DP‐2) via Knoevenagel polycondensation, which serve as the anion‐selective electrode coating for highly‐reversible and durable zinc‐based dual‐ion batteries (ZDIBs). Model reactions and theoretical modeling revealed the enhanced reactivity and reversibility of the Knoevenagel reaction on the water surface. On this basis, we demonstrated the on‐water surface 2D polycondensation towards V‐C2DPs films that show large lateral size, tunable thickness, and high chemical stability. Representatively, V‐C2DP‐1 presents as a fully crystalline and face‐on oriented film with in‐plane lattice parameters of a=b≈43.3 Å. Profiting from its well‐defined cationic sites, oriented 1D channels, and stable frameworks, V‐C2DP‐1 film possesses superior bis(trifluoromethanesulfonyl)imide anion (TFSI−)‐transport selectivity (transference, t_=0.85) for graphite cathode in high‐voltage ZDIBs, thus triggering additional TFSI−‐intercalation stage and promoting its specific capacity (from ~83 to 124 mAh g−1) and cycling life (>1000 cycles, 95 % capacity retention). [ABSTRACT FROM AUTHOR]

Owing to the variation of the characteristics due to the cationic substitution of diverse elements at both A and B sites, the new polycrystalline double perovskite BaBiFeMnO 6 , synthesized via a cost-efficient solid-state reaction route. Initial structural refinement by Rietveld analysis reveals material crystallised in dual phases i.e. monoclinic and orthorhombic. The respective cell parameters for monoclinic as well as orthorhombic phases are a = 5.5881 Å, b = 5.6541 Å, c = 7.9186 Å with cell angles α = γ = 900 and β = 89.90810 and a = 5.4807Å, b = 5.3583Å, c = 7.4045Å and refined angles are α = β = γ = 900 respectively. The microstructural interpretation of the present sample reflects a non-uniform distribution of the grains with an average grain size of 2.97 μm with a mean crystalline size of 342.65 nm. The Fourier-Transform Infrared Spectroscopy (FTIR) graph indicated that the sample belongs to the perovskite family. The impedance measurement was carried out in a selected frequency and an assigned temperature range to investigate the electrical features of the material which suggested the non-Debye type relaxation and negative temperature coefficient of resistance (NTCR). Furthermore, the thermistor constant (β) and temperature coefficient of resistance (TCR) contributed to investigating the NTCR characteristic of the sample under NTC-type thermistor applications. The room temperature dielectric constant is 1707.67 with a minimal tangent loss of 0.7069 at 100Hz frequency has been estimated by fitting the dielectric data by utilizing the Havrilliak-Negami function. The polarization (P) induced due to the maximum applied electric field of 1.287 kV is studied from the hysteresis loop plotted between them. The hysteresis loop indicates the ferroelectric property of the material with a lossy nature. The room temperature remnant magnetization (2M r) of 0.4424 emu/g and coercivity (2H c) of 6.2 kOe have been estimated from the M ∼ H loop. The potentiality of the material to be used as a viable candidate in various energy storage devices and supercapacitors is suggested by all of the characterisations in conjunction with the high value of ε r i.e. ∼80000 at 300 °C for the lower frequency. [ABSTRACT FROM AUTHOR]

PEGylation is a commonly used approach to prolong the blood circulation time of cationic liposomes. However, PEGylation is associated with the "PEG dilemma", which hinders binding and uptake into tumor cells. The cleavable PEG products are a possible solution to this problem. In the current research, doxorubicin-loaded cationic liposomes (Dox-CLs) surface-conjugated with a matrix metalloproteinase-2 (MMP-2)-sensitive octapeptide linker-PEG derivative were prepared and compared to non-PEGylated and PEGylated CLs in terms of size, surface charge, drug encapsulation and release, uptake, in vivo pharmacokinetics, and anticancer efficacy. It was postulated that PEG deshielding in response to the overexpressed MMP-2 in the tumor microenvironment increases the interaction of protected CLs with cellular membranes and improves their uptake by tumor cells/vasculature. MMP2-responsive Dox-CLs had particle sizes of ∼115-140 nm, surface charges of ∼+25 mV, and encapsulation efficiencies of ∼85-95%. In vitro cytotoxicity assessments showed significantly enhanced uptake and cytotoxicity of PEG-cleavable CLs compared to their non-cleavable PEG-coated counterparts or Caelyx®. Also, the chick chorioallantoic membrane assay showed great antiangiogenesis ability of Dox-CLs leading to target and prevent tumor neovascularization. Besides, in vivo studies showed an effective therapeutic efficacy of PEG-cleavable Dox-CLs in murine colorectal cancer with negligible hematological and histopathological toxicity. Altogether, our results showed that MMP2-responsive Dox-CLs could be served as a promising approach to improve tumor drug delivery and uptake. [ABSTRACT FROM AUTHOR]

Accurate control of core–shell lipopolyplex nanoparticles (LPP NPs) size is crucial for finely adjusting their biomedical performance. However, the synthesis of LPP NPs encounters challenges as two mixing-sensitive processes are involved in the synthesis, rendering precise control over particle size difficult using conventional batch methods. In this study, the formation of the nucleic acid/cationic polymer cores through electrostatic complexation and the subsequent encapsulation by lipid shells via self-assembly were conducted in microreactors, with polyadenylic acid (poly A) and branched polyethylenimine (bPEI) employed as the model system. By assessing the micromixing performance of the microreactors using the Villermaux-Dushman method, the characteristic time scale for electrostatic complexation between poly A and bPEI, as well as the self-assembly of lipids, was determined to be below 1 ms. The Reynolds number, governing micromixing performance, emerged as a crucial factor influencing the sizes of poly A/bPEI cores and LPP NPs. In the kinetic control region, characterized by rapid mixing, the size of poly A/bPEI remained slightly influenced by the N/P molar ratio and volumetric flow rate ratio, irrespective of concentration. The zeta potential, however, was primarily affected by the N/P molar ratio. In the case of LPP NPs, under optimized conditions of anionic lipid molar ratio, the size of LPP NPs was significantly influenced by the composition of lipid shells. This study establishes the foundation for elucidating the structure–activity relationship of LPP NPs. [ABSTRACT FROM AUTHOR]

The development of antimicrobial drugs with novel structures and clear mechanisms of action that are active against drug-resistant bacteria has become an urgent need of safeguarding human health due to the rise of bacterial drug resistance. The discovery of AMPs and the development of amphipathic peptidomimetics have lay the foundation for novel antimicrobial agents to combat drug resistance due to their overall strong antimicrobial activities and unique membrane-active mechanisms. To break the limitation of AMPs, researchers have invested in great endeavors through various approaches in the past years. This review summarized the recent advances including the development of antibacterial small molecule peptidomimetics and peptide-mimic cationic oligomers/polymers, as well as mechanism-of-action studies. As this exciting interdisciplinary field is continuously expanding and growing, we hope this review will benefit researchers in the rational design of novel antimicrobial peptidomimetics in the future. [ABSTRACT FROM AUTHOR]

Titanium silicon molecular zeolite (TS-1) plays an important role in catalytic reactions due to its unique nanostructure. The straight channel on TS-1 was parallel to the orientation of the short b-axis and directly exposed to the aperture of the 10-member ring with a diameter of 0.54 nm × 0.56 nm. This structure could effectively reduce the diffuse restriction of bulk organic compounds during the oxidative desulfurization process. As a kind of cationic polymer electrolyte, polydimethyldiallyl ammonium chloride (PDDA) contains continuous [C8H16N+Cl−] chain segments, in which the Cl− could function as an effective structure-directing agent in the synthesis of nanomaterials. The chain of PDDA could adequately interact with the [0 1 0] plane in the preparation process of zeolite, and then the TS-1 nanosheet with short b-axis thickness (6 nm) could be obtained. The pore structure of the TS-1 nanosheet is controlled by regulating the content of PDDA. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), N2 physical adsorption analysis, infrared absorption spectrum and ultraviolet–visible spectrum were used to determine the TS-1. The thinner nanosheets exhibit excellent catalytic performance in oxidative desulfurization of dibenzothiophene (DBT), in which the removal rate could remain at 100% after three recycles. Here, the TS-1 nanosheet with short b-axis thickness has a promising future in catalytic reactions. [ABSTRACT FROM AUTHOR]

The tailoring of the surface properties of cellulose nanocrystals (CNCs) to meet various requirements in environmental, food, and material areas has always been of great interest. In this study, the surface chemistry of CNCs was noncovalently modified by cetyltrimethylammonium bromide (CTAB), followed by characterizations and an investigation into its application as a coating material for interfacial interaction over various substrates. Due to the CTAB modification, the surface charge of the CNCs was neutralized, resulting in an increased size of each nanocrystal at the aqueous status and the aggregated microfibers when dried up. The CTAB modification not only decreased the crystallinity of the samples from 48.57% to 9.12%, but also reasonably hydrophobized the CNCs and decreased their total surface energy. Finally, the adsorption behavior of the CNCs and CTAB-CNCs over nonionic, anionic, and cationic polymers was investigated by ellipsometry. Based on the thickness of the CNC and CTAB-CNC layers over 2-Hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), and polyethyleneimine (PEI), we proposed that the adsorption behavior was overall influenced by electrostatic interaction, hydrogen bonding, and van der Waals forces, and the thickness of the adsorbed layers could be impacted by both the surface charge and the size of the crystals. [ABSTRACT FROM AUTHOR]

The interaction of cetyltrimethylammonium bromide (CTAB) with orange II has been studied spectrophotometrically. CTA‐Orange II complex was isolated from an aqueous solution with chloroform. The results indicate that the CTAB interacts in 1:1 stoichiometry with orange II. CTAB capped FeNPs were used as an adsorbent to the removal of CTA‐Orange II complex. Energy dispersive x‐ray spectroscope (EDX), Fourier transform infrared spectroscope (FTIR), surface scanning microscope (SEM), and transmission electron microscope (TEM) were used to determine the morphology of FeNPs. The effect of contact time, pH, and concentration of orange II were examined on the removal of dye and surfactant. The removal of orange II followed pseudo‐second‐order kinetic and Langmuir isotherm model. The maximum adsorption capacity (Qmax) of CTAB‐FeNPs for orange II was 1288.9 mg/g at 30°C. CTA‐Orange II complex was adsorbed onto the adsorbent through several types of interaction (e.g., electrostatic attractions, van der Waals interactions, hydrogen bonding and n‐π stacking interactions). The sorption of orange G was also studied at different CTAB concentrations. The results implied that the maximum sorption amount was almost half of the orange II adsorption. The findings reveal the feasibility of CTAB capped FeNPs to be used as an excellent and low‐cost adsorbent for the removal of various water pollutants, more specifically anionic dyes. [ABSTRACT FROM AUTHOR]

Host defense peptide-mimicking cationic oncolytic polymers have attracted increasing attention for cancer treatment in recent years. However, polymers with large amounts of positive charge may cause rapid clearance and severe off-target toxicity. To facilitate in vivo application, an alkaline phosphatase (ALP)-responsive oncolytic polypeptide precursor (C 12 -PLL/PA) has been reported in this work. C 12 -PLL/PA could be hydrolyzed into the active form of the oncolytic polypeptide (C 12 -PLL) by the extracellular alkaline phosphatase within solid tumors, thereby resulting in the conversion of the negative charge to positive charge and restoring its membrane-lytic activity. Detailed mechanistic studies showed that C 12 -PLL/PA could effectively destroy cancer cell membranes and subsequently result in rapid necrosis of cancer cells. More importantly, C 12 -PLL/PA significantly inhibited the tumor growth in the 4T1 orthotopic breast tumor model with negligible side effects. In summary, these findings demonstrated that the shielding of the amino groups with phosphate groups represents a secure and effective strategy to develop cationic oncolytic polypeptide, which represents a valuable reference for the design of enzyme-activated oncolytic polymers. Recently, there has been a growing interest in fabricating host defense peptide-mimicking cationic oncolytic polymers for cancer therapy. However, there remain concerns about the tumor selectivity and off-target toxicity of these cationic polymers. In this study, an alkaline phosphatase-responsive oncolytic polypeptide precursor (C 12 -PLL/PA) has been developed to selectively target cancer cells while sparing normal cells. Mechanistic investigations demonstrated that C 12 -PLL/PA effectively disrupted cancer cell membranes, leading to rapid necrosis. Both in vitro and in vivo experiments showed promising anticancer activity and reliable safety of C 12 -PLL/PA. The findings suggest that this synthetic enzyme-responsive polypeptide holds potential as a tumor-specific oncolytic polymer, paving the way for future applications in cancer therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Designing materials capable of disinfecting water without releasing harmful by-products is an ongoing challenge. Here, we report a novel polycationic sponge material synthesized from chitosan derivatives and cellulose fibers, exhibiting antibacterial properties. The design of such material is based on three key principles. First, the formation of a highly porous structure through cryogelation for an extensive surface area. Second, the incorporation of cationic quaternary ammonium moieties onto chitosan to enhance bacterial adsorption and antibacterial activity. Lastly, the reinforcement of mechanical properties through integration of cellulose fibers. The presented sponge materials exhibit up to a 4-log (99.99%) reduction within 6 h against both gram-positive B. subtilis and gram-negative E. coli. Notably, QCHI90/Cell, with the highest surface charge, exhibits a 2–4.5 log reduction within 1 h of incubation time. The eco-friendly synthesis from water and readily available biomaterials, along with cost-effectiveness and simplicity, underscores its versatility and feasibility of upscaling. Together with its outstanding antibacterial activity, this macroporous biomaterial emerges as a promising candidate for water disinfection applications. [ABSTRACT FROM AUTHOR]

Background: Chronic rhinosinusitis (CRS) is an inflammatory disease affecting the sinuses or nose. Persistent inflammatory responses can lead to tissue remodeling, which is a pathological characteristics of CRS. Activation of fibroblasts in the nasal mucosal stroma, differentiation and collagen deposition, and subepithelial fibrosis have been associated with CRS. Objectives: We aimed to assess the inhibitory effects of doxycycline and deoxycholic acid-polyethyleneimine conjugate (DA3-Doxy) on myofibroblast differentiation and extracellular matrix (ECM) production in nasal fibroblasts stimulated with TGF-β1. Methods: To enhance efficacy, we prepared DA3-Doxy using a conjugate of low-molecular-weight polyethyleneimine (PEI) (MW 1800) and deoxycholic acid (DA) and Doxy. The synthesis of the DA3-Doxy polymer was confirmed using nuclear magnetic resonance, and the critical micelle concentration required for cationic micelle formation through self-assembly was determined. Subsequently, the Doxy loading efficiency of DA3 was assessed. The cytotoxicity of Doxy, DA3, PEI, and DA-Doxy in nasal fibroblasts was evaluated using the WST-1 assay. The anti-tissue remodeling and anti-inflammatory effects of DA3-Doxy and DA3 were examined using real-time polymerase chain reaction (Real-time PCR), immunocytochemistry, western blot, and Sircol assay. Results: Both DA3 and DA3-Doxy exhibited cytotoxicity at 10 μg/ml in nasal fibroblasts. Doxy partially inhibited α-smooth muscle actin, collagen types I and III, and fibronectin. However, DA3-Doxy significantly inhibited α-SMA, collagen types I and III, and fibronectin at 5 μg/ml. DA3-Doxy also modulated TGF-β1-induced changes in the expression of MMP 1, 2, and 9. Nonetheless, TGF-β1-induced expression of MMP3 was further increased by DA3-Doxy. The expression of TIMP 1 and 2 was partially reduced with 5 μg/ml DA3-Doxy. Conclusions: Although initially developed for the delivery of genetic materials or drugs, DA3 exhibits inhibitory effects on myofibroblast differentiation and ECM production. Therefore, it holds therapeutic potential for CRS, and a synergistic effect can be expected when loaded with CRS treatment drugs. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal CrystEngComm. It highlights various papers and communications published in the journal, including topics such as hydrogen storage, coordination polymers, luminescent sensors, and chemical solution deposition. The cover image features the Tembleque Aqueduct World Heritage Site in Mexico. The journal is published by the Royal Society of Chemistry, a leading chemistry community that connects the world with the chemical sciences. [Extracted from the article]

This research paper focuses on the removal of the nonsteroidal anti-inflammatory drug, ibuprofen, from an aqueous solution using a dissolved air flotation process. The comparison of different types of cationic surface-active agents such as cetyltrimethyl ammonium bromide (CTAB), tetrabutyl ammonium bromide (TBAB), and octyltrimethyl ammonium bromide (OTAB) have been employed to scrutinize the effective removal of the ecotoxic pharmaceutically active compound. The work included the influencing parameters such as pressure, contact time, surfactant dosage, pH, flow rate, and initial concentration owing to the best-optimized conditions. The maximum removal rate of 96.09% was achieved at 15 min for CTAB, TBAB had 62.36% at 45 min, and 89.6% was obtained for OTAB at 30 min, with 50 mg L−1 as the initial concentration and pH = 4. The removal rate was better with the optimized dosage of CTAB at 0.6 g, TBAB at 1.2 g, and OTAB at 1.0 g. It was observed that the geometric shape of the surface-active agents had greater impacts on the contaminants' efficiency. CTAB and OTAB were combined to find out the best possible removal rate of contaminants. The synergistic effect augments surfactant-based occurrence to be better in forming a good foaming effect and tends to have a lower critical micelle concentration (CMC). From the evaluation of kinetic models, pseudo-second-order flotation kinetics fitted the experimental data best. Furthermore, the formed metabolites that had been identified using gas chromatography-mass spectrometry were found to be less toxic than the parenting compounds. [ABSTRACT FROM AUTHOR]

Amphiphilic cationic polymers mimicking the membrane‐disrupting mechanism of natural antimicrobial peptides displays high‐efficacy bactericidal activity and meanwhile good biocompatibility, while electrostatic adsorption enables bacteria to adhere to substrate surfaces, effectively lowering the antimicrobial effect, so it is worthwhile to tackle the problem of bacterial adhesion to prolong its antibacterial activity. Herein, a kind of polyquaternium latex (PQL) was synthesized to coat polypropylene nonwoven fabrics (PPNFs) with bacterial repellency and rapid biocidal activity toward both Staphylococcus aureus and Escherichia coli. Compared with polyquaternium solution coatings, latex coatings provided PPNFs with unique microscopic morphology and surface chemistry rich in polyoxyethylene moieties, achieving better resistance to bacterial adhesion, and meanwhile PQL coated PPNFs also delivered 99% killing rates against both bacteria within 2 min. After exposure to ultrasonic cleaning for 4 h, PQL modified PPNFs still demonstrated good bactericidal activity. Moreover, they also displayed low cytotoxicity. This work provides guidance for the design of antibacterial and antiadhesion coatings to combat bacterial infection. [ABSTRACT FROM AUTHOR]

Background: Transfection is an important analytical method for studying gene expression in the cellular environment. There are some barriers to efficient DNA transfection in host cells, including circumventing the plasma membrane, escaping endosomal compartmentalization, autophagy, immune sensing pathways, and translocating the nuclear envelope. Therefore, it would be very useful to introduce an optimum transfection approach to achieve a high transfection efficiency in the Vero cell line. The aim of this study was to compare various transfection techniques and introduce a highly efficient method for gene delivery in Vero cells. Methods: In the current study, three transfection methods were used, including chemical transfection, electroporation, and lentiviral vector transduction, to obtain the optimum transfection conditions in the Vero cell line. Vero cells were cultured and transfected with chemical transfection reagents, electroporation, or HIV-1-based lentivectors under different experimental conditions. Transfection efficiency was assessed using flow cytometry and fluorescence microscopy to detect GFP-positive cells. Results: Among the tested methods, TurboFect™ chemical transfection exhibited the highest efficiency. Optimal transfection conditions were achieved using 1 µg DNA and 4 µL TurboFect™ in 6 × 104 Vero cells. Conclusion: TurboFect™, a cationic polymer transfection reagent, demonstrated superior transfection efficiency in Vero cells compared with electroporation and lentivirus particles, and is the optimal choice for chemical transfection in the Vero cell line. [ABSTRACT FROM AUTHOR]

The emerging wearable skin-like electronics require the ultra-flexible organic transistor to operate at low voltage for electrical safety and energy efficiency and simultaneously enable high field-effect mobility to ensure the carrier migration ability and the switching speed of circuits. However, the currently reported low-voltage organic transistors generally present low mobility, originating from the trade-off between molecular polarity and surface polarity of the dielectrics. In this work, the orientation polarization of the dielectric is enhanced by introducing a flexible quaternary ammonium side chain, and the surface polarity is weakened by the shielding effect of the nonpolar methyl groups on the polar nitrogen atom. The resulting antisolvent QPSU dielectric enables the high-dielectric constant up to 18.8 and the low surface polarity with the polar component of surface energy only at 2.09 mJ/m2. Such a synergistic polarization engineering between orientation polarization and surface polarity makes the solution-processed ultraflexible transistors present the ultralow operational voltage down to −3 V, the ultrahigh charge-carrier mobility up to 8.28 cm2 V−1 s−1 at 1 Hz, excellent cyclic operational stability and long-term air stability. These results combined with the ultrathin thickness of transistor as low as 135 nm, the ultralight mass of 0.5 g/m2, the conformal adherence capability on human skin and 1-μm blade edge, and the strong mechanical robustness with stable electrical properties for 30,000 bending cycles, open up an available strategy to successfully realize low-voltage high-mobility solution-processed organic transistor, and presents the potential application of QPSU dielectric for the next-generation wearable imperceptible skin-like electronics. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is one of the most refractory organisms to antibiotic treatment and appears to be one of the least susceptible to photodynamic treatment. TMPyP is effective in the photoinactivation of P. aeruginosa, and the co‐administration with the cationic polymer Eudragit®‐E100 (Eu) potentiates this effect against isolates both sensitive and resistant to antibiotics. The fluorescent population (>98%) observed by flow cytometry after exposure to Eu + TMPyP remained unchanged after successive washings, indicating a stronger interaction/internalization of TMPyP in the bacteria, which could be attributed to the rapid neutralization of surface charges. TMPyP and Eu produced depolarization of the cytoplasmic membrane, which increased when both cationic compounds were combined. Using confocal laser scanning microscopy, heterogeneously distributed fluorescent areas were observed after TMPyP exposure, while homogeneous fluorescence and enhanced intensity were observed with Eu + TMPyP. The polymer caused alterations in the bacterial envelopes that contributed to a deeper and more homogeneous interaction/internalization of TMPyP, leading to a higher probability of damage by cytotoxic ROS and explaining the enhanced result of photodynamic inactivation. Therefore, Eu acts as an adjuvant without being by itself capable of eradicating this pathogen. Moreover, compared with other therapies, this combinatorial strategy with a polymer approved for pharmaceutical applications presents advantages in terms of toxicity risks. [ABSTRACT FROM AUTHOR]

The non-toxic amphiphilic bottlebrush polymers capable of self-organization on various interfaces and including cerium ions in structural assemblies without changing their biological properties have great importance for medicine and pharmacy. In the work, we studied the self-assembly in mixed monolayers of two copolymers – methoxy[oligo(propylene glycol)] methacrylate and methoxy[oligo(ethylene glycol)] methacrylate (PK) and its analogue with N-[3-(dimethylamino)propyl]methacrylamide) units quaternized with methyl iodide (PKq), and cholesterol on the aqueous subphase-air interface in the present of cerium compounds. The effect of the polymer-cerium composition on the oxidoruductase activity was investigated as well. The cationic polymer PKq was shown to exhibit higher specific activity of antioxidant enzymes than the non-ionic PK copolymer, increasing the activity of SOD by 20%, catalase – by 15%, GR – by 24%, G6PD – by 88%, and AlDH – by 10%. In the presence of cerium compounds (Ce(NO3)3, NH4[Ce(NO3)3], CeO2 nanoparticles) these effects increased significantly. Cholesterol in a monolayer of polymers contributed to an increase of compressibility modulus Cs−1 under the influence of cerium ions in mixed monolayers by approximately two times compared to mixed Chol+polymers monolayers on water, and Cs−1 became 640 mN/m for Chol+PK monolayers and 700 mN/m for Chol+PKq monolayers. AFM and wettability study suggest elastic structure of transferred mixed monolayers that is suitable for designing a drug delivery system. [ABSTRACT FROM AUTHOR]

Oropharyngeal candidiasis, an opportunistic fungal infection, is caused by Candida albicans. Conventional formulations of antifungal drug, miconazole nitrate (MN), have limited retention on the infected oral mucosa, leading to its rapid clearance from the affected site. Aim of present study was to design and optimize MN buccal mucoadhesive wafer formulation for enhanced retention time as well as controlled drug release. Varying ratios of anionic, cationic and nonionic polymers were used to prepare wafers by freeze-drying method. Drug excipient interaction studies were performed by fourier transform infrared (FT-IR) and differential scanning calorimetry (DSC) analysis. Formulations were further evaluated by various wafer quality assessment parameters. Scanning electron microscopy (SEM) analysis and X-ray diffraction (XRD) studies were performed for surface analysis and solid state characterization, respectively, of prepared formulations. In vitro drug release studies of optimized formulations were performed and release kinetics was evaluated. Wafer formulations with anionic polymers exhibited acceptable results of swelling, adhesiveness and folding endurance analysis. Optimized formulations showed controlled release of MN by non-Fickian diffusion. Results suggest that buccoadhesive wafer formulated by anionic polymers may be utilized to achieve desired therapeutic effects of MN. [ABSTRACT FROM AUTHOR]