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Drugs treatment including antibiotics or herbal medicines cannot cure osteomyelitis effectively accompanied by drug‐resistance bacteria and even amputation after long‐term debridement. Herein, a materioherbological strategy is utilized to construct a smart nanovector of cationic starch (CS) modified curcumin nanoparticles (CS@Cur NPs) for treating methicillin‐resistant Staphylococcus aureus (MRSA) induced osteomyelitis. On the one hand, CS modification can reduce the π–π accumulation of curcumin to endow the nanocomposite with excellent water solubility. On the other hand, the hydroxyl group in the curcumin is hydrogen‐bonded to the carbonyl group in the monomer (methyl methacrylate, MMA) of CS, resulting in a decrease in both the bandgap (between the highest and lowest occupied molecular orbitals, labeled as ΔE) and the S1–T1 energy gap (ΔES‐T) while the spin–orbital coupling (SOC) values increase, which benefits the formation of triplet‐state molecules under ultrasonic irradiation, significantly improving the yields of reactive oxygen species (ROS) capacity. The CS@Cur NPs nanocomposite constructed in this paper produced a large number of ROS synergic targeting effects under continuous 15 min ultrasonic irradiation, the clearance rate of MRSA infection induced osteomyelitis in rats can be as high as 99.93%. This study provides a new therapeutic strategy for the treatment of osteomyelitis induced by pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Cationic polymers have been identified as a promising type of antibacterial molecules, whose bioactivity can be tuned through structural modulation. Recent studies suggest that the placement of the cationic groups close to the core of the polymeric architecture rather than on appended side chains might improve both their bioactivity and selectivity for bacterial cells over mammalian cells. However, antibacterial main-chain cationic polymers are typically synthesized via polycondensations, which do not afford precise and uniform molecular design. Therefore, accessing main-chain cationic polymers with high degrees of molecular tunability hinges upon the development of controlled polymerizations tolerating cationic motifs (or cation progenitors) near the propagating species. Herein, we report the synthesis and ring-opening metathesis polymerization (ROMP) of N-methylpyridinium- fused norbornene monomers. The identification of reaction conditions leading to a well-controlled ROMP enabled structural diversification of the main-chain cationic polymers and a study of their bioactivity. This family of polyelectrolytes was found to be active against both Gram-negative (Escherichia coli) and Gram-positive (Methicillin-resistant Staphylococcus aureus) bacteria with minimal inhibitory concentrations as low as 25 μg/mL. Additionally, the molar mass of the polymers was found to impact their hemolytic activity with cationic polymers of smaller degrees of polymerization showing increased selectivity for bacteria over human red blood cells. [ABSTRACT FROM AUTHOR]

Using suitable chemically stabilized materials to solve the moisture-related damages on the road pavement is still essential. This study investigated the influence of cationic asphalt emulsion (CAE) on a hybrid alkali-activated binder (HAB) consisting of fly ash, hydrated lime, and solid sodium hydroxide for the chemically stabilized road base material. Adding CAE to HAB would introduce the water-repellent and elastic properties of HAB. Crushed rock (CR) treated with HAB binder prepared with two concentrations of CAE (HAB-CAEs) was characterized using a test series of compaction, unconfined compressive strength, resilient modulus, and water absorption. The compaction test results showed that CAE could decrease the optimum water content and air voids at the maximum dry density. Using CAE increased the strength of the HAB-CAE-treated CR, resulting in a sufficient compressive strength of the flexible pavement base. In addition, the HAB-CAE-treated CR had a proficient energy absorption under a static loading condition. The addition of CAE to the HAB-treated CR also provided resilient modulus and stiffness values higher than those of the conventional cement-treated base material with less water absorption. Therefore, HAB-CAE could be a viable option as a sustainable pavement base material. [ABSTRACT FROM AUTHOR]

Experimental and theoretical insights into polymerization of para-N,N-disubstituted aminostyrene monomers (St-4-NR2, R = Me, Et, Ph) using cationic α-diimine palladium complexes have been initially reported. The effects of the catalyst structure and monomer substituent were studied systematically. Polymerization turnover frequency (TOF) was shown to decrease in the order of monomer substituents Me > Et > Ph, whereas the molecular weight of the produced polymers showed an opposite trend (Me < Et < Ph). Methanol-mediated polymerization of para-N,N-dimethylaminostyrene (DMAS), along with polymer chain-end analysis, and palladium intermediate isolation proved that palladium-initiated DMAS polymerization obeyed a cationic mechanism. Comprehensive theoretical calculations further revealed that the carbocation was generated from the insertion of DMAS into the palladium center rather than the polarization of the methyl palladium intermediate with a coordinated DMAS. The produced amine-functionalized amorphous polystyrenes have low stereoregularity and exhibit good hydrophilic properties. The poly(para-N,N-disphenylaminostyrene) is a luminescent polymer and shows fluorescence properties, rendering this material a promising candidate for versatile potential applications. [ABSTRACT FROM AUTHOR]

Due to their excellent photoelectric conversion efficiency and low preparation cost, perovskite solar cells (PSCs) have attracted much attention from researchers and developed rapidly in the past decade. However, the stability and efficiency of perovskite photovoltaic devices still need to be improved for their practical applications. It is mainly because the perovskite thin films are inevitably defective to some extent (such as points defects and extrinsic defects), leading to the occurrence of non‐radiative recombination (NRR) inside the device and at the interface, which is closely related to the stability and efficiency of perovskite materials. Therefore, exploring reliable passivation strategies is essential to overcome the adverse effects of NRR losses of such point defects. Here, this article summarizes the perovskite solar cells, including the crystal structure and calculations of electronic properties of perovskites, composition, and principles of operation of perovskite solar cells, and more importantly, different passivation strategies, including Lewis acid‐base passivation, anionic and cationic passivation, polymer passivation, and alkyl halogen ammonium passivation for the defects involved in perovskite materials. The passivation effects of these strategies and their regulation mechanisms of point defects involving perovskite materials are also presented. We also discuss the intrinsic relationship between crystal defects and device stability and look forward to feasible defect passivation strategy options for future research. [ABSTRACT FROM AUTHOR]

Two new cyclometalated cationic iridium(III) complexes containing norbornene-substituted pyridylbenzimidazole ancillary ligands were synthesized. On the base of carbazole- and iridium-containing norbornene monomers electroluminescent copolymers were prepared by metathesis polymerization method. Photophysical properties of the synthesized compounds were investigated. Polymeric products revealed intense photoluminescence and electroluminescence of yellow color. [ABSTRACT FROM AUTHOR]

Disordered rock‐salt (DRS) type active materials are highly significant because of their large reversible capacities, which are due to their unique Li+ diffusion pathway and the redox capabilities of cationic transition metals (TMs) and anionic O ions. Loosely crystalline DRS materials have weak covalent bonds between TMs and O, increasing the O redox contribution and thereby enhancing their capacities. In this study, Mn‐based positive electrode materials with DRS structures are activated and stabilized by mechanochemical doping of nonmetallic elements P and B into interstitial sites. Synthesized Li0.90Mn0.84P0.04O2 (LMPO5) exhibits an initial discharge capacity of 346 mAh g−1 (1050 Wh kg−1) during charging/discharging. Li0.91Mn0.83B0.10O2 (LMBO5) has a moderately expanded lattice size, which facilitates high‐capacity retention during cycling (≈284 mAh g−1 at the 30th cycle). The structural properties of the synthesized active materials are extensively characterized. By introducing nonmetallic elements into the interstitial sites of Mn‐based materials, inexpensive, high‐capacity, and long‐cycling/calendar‐life Co/Ni‐free monometallic positive electrode materials may be further developed. [ABSTRACT FROM AUTHOR]

New hybrid metal organic framework based polymer nanocomposite (ZIF-8/NC-PU) and interpenetrating polymer gel nanocomposites (NC-PU) were prepared for the adsorption of cationic (Rh-B) and anionic (IC) dyes from aqueous solution. The characterisation of the ZIF-8 based composites and gel composites is carried out using FT-IR and SEM analysis to investigate the chemical composition and morphology of the sample. Moringa oleifera seed pod based nanocellulose (5 wt%) is used as the filler in NC-PU gel composites and ZIF-8/NC-PU MOF composites. The optimal level of the most significant identified variables affecting the adsorption process were determined by the response surface methodology (RSM) using Plackett–Burman and Box–Behnken design. Adsorption capacity increased with the increase in dosage of the adsorbent, pH and initial dye concentration. Plackett–Burman was performed for the experiments involving the dyes Rh-B and Indigo carmine dyes. It gave 12 experiments in each trials and resulted in 3 significant parameters. Box–Behnken was further used to determine the optimum parameters for the adsorption keeping PU weight percentage as 3. The percentage uptake predicted by the model is in good agreement with the experimental values. The findings assume that the adsorbents could be used effectively as highly efficient adsorbents for the removal of multiple dyes from wastewater. [ABSTRACT FROM AUTHOR]

Hierarchical Beta zeolites with interconnected intracrystalline mesopores and high structural stability are highly attractive for catalytic applications involving bulky reactants. Here, by introducing a suitable amount of polydiallyldimethylammonium chloride into the initial synthesis system, micron-sized Beta zeolite crystals with abundant hierarchical porosity (Beta-H) were hydrothermally synthesized. The sample named Beta-H_1 exhibited very high catalytic activity and durability for the Friedel–Crafts acylation of anisole with acetic anhydride. A 92% conversion rate of acetic anhydride could be achieved after 1 h of reaction in a fixed bed reactor, and 71% conversion still remained after 10 h, much better than the rate for conventional Beta zeolite (which decreased rapidly from 85% to 37% within 10 h). The enhanced catalytic performance of Beta-H zeolites could be mainly attributed to the relatively lower strong acid density and the faster transport rate of the hierarchical zeolites. In addition, Beta-H showed high structural stability and could be easily regenerated via high-temperature calcination without obvious loss in catalytic activity, demonstrating its great potential for catalytic applications in the industrially important Friedel–Crafts acylation process. [ABSTRACT FROM AUTHOR]

Bacterial infection and impaired angiogenesis make the treatment of diabetic foot ulcers (DFU) extremely challenging. Cationic polymers are expected to treat infected wounds due to their excellent antibacterial properties, but still, it is difficult to meet the therapeutic needs of pro‐angiogenesis and anti‐infections due to their simple construction units and outmoded synthesis methods. Herein, a cationic poly(pentahydropyrimidine) (PPHP) library with strong modifiability is synthesized to construct a hybrid hydrogel with synergistic therapeutic effects for the treatment of infected DFUs. It is found that the as‐synthesized hybrid hydrogel can up‐regulate angiogenesis‐related gene (HIF‐1, VEGF, and bFGFR/bFGF) expression and targeted disruption of bacterial cell membranes, which finally promotes the healing of infected DFU (wound healing rate: 92%) within 10 days. This hydrogel, thus, holds great promise in developing new strategies to significantly enhance the treatment of DFU and other bacterial‐infected pathological diagnoses. [ABSTRACT FROM AUTHOR]

The existence of fine oil droplets that are difficult to coalesce greatly reduces the oil–water separation efficiency of alkali‒surfactant‒polymer (ASP) flooding-produced water. In order to improve the oil–water separation efficiency and promote the reinjection of ASP-produced water, a novel cationic graft copolymer CDC was obtained by ultrasonically assisted copolymerization of chitosan and dimethyl diallyl ammonium chloride under the initiation of cerium ions. The copolymer CDC was characterized by FT-IR, XRD, TGA and SEM, and it was confirmed that the grafting reaction proceeded successfully. The flocculation effect of copolymer CDC on ASP-produced water (Nan 4–8, pH = 7.83; Sanyuan-6, pH = 9.95) was investigated. Copolymer CDC has better oil removal rate (90.5%) and light transmittance (95.25%) to Nan 4–8 produced water compared with Sanyuan-6-produced water. It has a better oil removal effect when the initial pH of produced water is 6–7 and the temperature is 30 °C. After the addition of CDC, the large-diameter oil droplets in produced water will coalesce and separate. It may be that under weak acid or neutral conditions, the electrostatic attraction of produced water is enhanced, compressing the double electron layer of oil droplets, and destroying the stability of oil droplets. In addition, the hydrophobic effect of –CH=CH2 in CDC molecules increases the hydrophobic association between molecules and increases the probability of oil droplet collision during the flocculation process. [ABSTRACT FROM AUTHOR]

Trioxane (TOX), which is usually produced from formaldehyde catalyzed by acid-catalysts, is an important polymerizing monomer to produce high-performance plastics polyoxymethylene polymers (POMs). In order to reduce the separation cost and increase the catalytic activity, hierarchical Beta zeolites with different pore size were synthesized by PDDA and used for TOX produce from formaldehyde in this work. Hierarchical Beta zeolites' average pore size increased with the increasing of PDDAs' molecular weight. Compare to conventional Beta zeolite, it exhibited a higher catalytic performance with 95.13% selectivity and 2118 g/kg/h space–time yield of TOX due to its excellent diffusion performance from extra mesopore. The HCHO conversion and space–time yield of TOX increase first and then decrease with the pore size increasing. Further research showed that the decrease of catalytic activity is mainly due to the increase of extra-framework Al percent. This work illustrates the influence of both pore size and extra-framework Al content in hierarchical Beta zeolites for TOX produce from formaldehyde reaction. [ABSTRACT FROM AUTHOR]

Since the skin limits the distribution of intradermal vaccines, a large number of dendritic cells in the skin cannot be fully utilized to elicit a more effective immune response. Here, we loaded the antigen to the surface of the flagellate bacteria that was modified by cationic polymer, thus creating antigen-loaded flagellate bacteria (denoted as 'FB-Ag') to overcome the skin barrier and perform the active delivery of antigen in the skin. The FB-Ag showed fast speed (∼0.2 μm s−1) and strong dendritic cell activation capabilities in the skin model in vitro. In vivo, the FB-Ag promoted the spread of antigen in the skin through active movement, increased the contact between Intradermal dendritic cells and antigen, and effectively activated the internal dendritic cells in the skin. In a mouse of pulmonary metastatic melanoma and in mice bearing subcutaneous melanoma tumor, the FB-Ag effectively increased antigen-specific therapeutic efficacy and produced long-lasting immune memory. More importantly, the FB-Ag also enhanced the level of COVID-19 specific antibodies in the serum and the number of memory B cells in the spleen of mice. The movement of antigen-loaded flagellate bacteria to overcome intradermal constraints may enhance the activation of intradermal dendritic cells, providing new ideas for developing intradermal vaccines. [Display omitted] [ABSTRACT FROM AUTHOR]

Poly(2-isopropenyl-2-oxazoline) (PiPOx) is a functional polymer showing great potential for the development of smart biomaterials. The straightforward synthesis and post-polymerization functionalization of PiPOx offers many opportunities for tailoring the properties of the polymer towards biomaterials. In this study we report for the first time PiPOx-based cationic charged polymethacrylamides with amino acid side chains that can complex siRNA and promote transfection in vitro. Therefore, PiPOx was fully modified via ring opening addition reactions with the carboxylic acid groups of a series of N -Boc- L -amino acids and their reaction kinetics were investigated. Based on the determined kinetic constants, another series of PiPOx-based copolymers with balanced hydrophilic/hydrophobic content of N -Boc- L -amino acids were obtained via one-pot modification reaction with two different N -Boc- L -amino acids. The N -Boc protected homopolymers and related copolymers were deprotected to obtain (co)polymers with the targeted side chain cationic charged units. The (co)polymers' structures were fully investigated via FT-IR and 1H NMR spectroscopy, size exclusion chromatography (SEC), and TGA–DSC–MS analysis. The polarimetry measurements revealed that the homopolymers retain their chiroptical properties after post-modification, and a sign inversion is noticed from (L) N -Boc-protected analogues to (D) for the TFA cationic charged homopolymers. Generally, cationically charged homopolymers with hydrophilic amino acids on the side chain showed efficient complexation of siRNA, but poor transfection while cationic copolymers having both tryptophan and valine or proline side chains revealed moderate siRNA binding, high transfection efficiency (> 90% of the cells) and potent gene silencing with IC 50 values down to 5.5 nM. Particularly, these cationic copolymers showed higher gene silencing potency as compared to the commercial JetPRIME® reference, without reducing cell viability in the concentration range used for transfection, making this a very interesting system for in vitro siRNA transfection. [Display omitted] [ABSTRACT FROM AUTHOR]

Supramolecular organic frameworks (SOFs) have emerged as a promising class of organic porous materials with vast potential as nanocarriers for combination therapy. Here, we successfully construct an anionic flexible supramolecular organic framework (TPP-SOF) by leveraging multiple host-guest interactions. TPP-SOF is fabricated by the hierarchical orthogonal assembly between anionic water-soluble dimacrocyclic host (P5CD), porphyrin photosensitizers (TPP), and ROS-sensitive thioketal linked adamantane dimer (Ada-S-Ada). TPP-SOF exhibits pH-dependent activation of 1O 2 production, which further facilitates the cleavage of Ada-S-Ada linker and promotes the disintegration of the framework. Moreover, leveraging electrostatic and hydrophobic interactions, the anionic TPP-SOF serves as an effective platform for loading cationic photosensitizer IR780 and chemotherapeutic prodrug PhenPt(IV), leading to the formation of supramolecular nanoparticles (IR780/Pt@TPP-SOF) for synergistic therapy. The obtained nanoparticles exhibit good stability, efficient generation of 1O 2 , and photothermal performance. In vitro and in vivo studies indicate that IR780/Pt@TPP-SOF exhibits remarkable synergistic chemo/PDT/PTT effects under 808 and 660 nm light irradiation. This study showcases a deep insight for the development of SOFs and a new approach for delivering cationic drugs and constructing synergistic combination therapy systems. In this work, a pH/ROS-responsive anionic flexible supramolecular organic framework, TPP-SOF , was innovatively designed by the hierarchical orthogonal assembly, to co-deliver cationic photosensitizer IR780 and prodrug PhenPt(IV) for synergistic cancer therapy. The drug-loaded TPP-SOF is termed IR780/Pt@TPP-SOF , in which the photoactivity of porphyrin within TPP-SOF could be activated under acidic conditions, the 1O 2 generated by the photosensitizers could break the thioketal bonds in Ada-S-Ada , leading to the disassembly of the framework and releasing the drugs. This supramolecular drug delivery system displays good biocompatibility and exhibits remarkable synergistic chemo/PDT/PTT effects. [Display omitted] [ABSTRACT FROM AUTHOR]

Environmental pollution by phosphate and nitrate ions has become a serious problem. The innovation of cacao husk as an adsorbent and sustainable material can be a solution for absorbing phosphate and nitrate ions. Cocoa husk (CH) derived from the matured cocoa fruit's remaining pod material that often discarded as waste. The aim of this research is to develop an environmentally friendly and economical cacao husk (CH) based material for the absorption of phosphate and nitrate ions from aqueous solutions. CH surface modification is made by reacting the cationic polymer 2-[(methacryloyloxy)ethyl]trimethylammonium (META), into CH treatment (CH-T). Successful surface modification of CH-T with cationic polymers was confirmed to improve the surface properties for the removal of phosphate and nitrate ions. The surface charge morphology, structure, pore distribution and stability of the modified CH-T were investigated by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Branueur-Emmet-Teller (BET) and elemental analysis. 0.3 grams of CH-T modified with 75% cationic polymer with stirring at 70 rpm for 180 minutes at 50°C was reported as the best modification condition. Removal efficiencies of phosphate and nitrate ions increased after adding quaternary ammonium to CH-T to 96% and 93.4%, respectively. These results indicate that CH modification has prospective as a low-cost catalyst for wastewater treatment. [ABSTRACT FROM AUTHOR]

As the development of tight gas fields enters the stable production stage, condensate oil forms a complex oil--water emulsifying system under the action of bubble drainage agent, corrosion inhibitor, hydrate inhibitor, and other additives to increase and stabilize production, as well as the formation of particulate matter. A new demulsification and flocculation agent suitable for condensate emulsifying system is developed to make the system unstable and the oil beads coalesce. In this paper, a polyether--quaternary ammonium salt reverse demulsifier (PPA) was synthesized by grafting a cationic group onto a five-membered block polyether X-75. A new type of demulsification--flocculation agent (CQ) was obtained through the complex modification of PPA and inorganic coagulant polyaluminum ferric chloride. Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and gel chromatograph were used to characterize the group and molecular structure. The reaction parameters were optimized by single-factor experiment and the response surface method, and the demulsification--flocculation mechanism was determined by zeta potential, interfacial tension, and fractal dimension. Results showed the PPA demulsifier has active groups (block polyether) and cationic groups (polyquaternary ammonium salt) at the oil--water interface at the same time and can play a synergistic role between them. Single-factor experiment and response surface optimization showed CQ concentration and temperature were key factors affecting the demulsification-- flocculation effect. When CQ concentration was 547 mg/L, settling temperature was 27.9°C and PPA accounted for 71%. After settling for 30 min, the oil content and the concentration of total suspended solids (TSS) in the water decreased to 21.26 and 7.0 mg/L, respectively, which met the water quality requirements of reinjection (oil content ≤ 30 mg/L, TSS concentration ≤ 15 mg/L). By neutralizing and displacing active substances at the oil--water interface and sweeping by net trapping, CQ can coagulate oil beads and suspended particles to form large flocs and realize the efficient separation of oil beads, suspended particles, and water. [ABSTRACT FROM AUTHOR]

Aluminium adjuvants are commonly used in vaccines to stimulate the immune system, but they have limited ability to promote cellular immunity which is necessary for clearing viral infections like hepatitis B. Current adjuvants that do promote cellular immunity often have undesired side effects due to the immunostimulants they contain. In this study, a hybrid polymer lipid nanoparticle (HPLNP) was developed as an efficient adjuvant for the hepatitis B surface antigen (HBsAg) virus-like particle (VLP) vaccine to potentiate both humoral and cellular immunity. The HPLNP is composed of FDA approved polyethylene glycol-b-poly (l-lactic acid) (PEG-PLLA) polymer and cationic lipid 1, 2-dioleoyl-3-trimethylammonium-propane (DOTAP), and can be easily prepared by a one-step method. The cationic optimised vaccine formulation HBsAg/HPLNP (w/w = 1/600) can maximise the cell uptake of the antigen due to the electrostatic adsorption between the vaccine nanoparticle and the cell membrane of antigen-presenting cells. The HPLNP prolonged the retention of the antigen at the injection site and enhanced the lymph node drainage of antigen, resulting in a higher concentration of serum anti-HBsAg IgG compared to the HBsAg group or the HBsAg/Al group after the boost immunisation in mice. The HPLNP also promoted a strong Th1-driven immune response, as demonstrated by the significantly improved IgG2a/IgG1 ratio, increased production of IFN-γ, and activation of CD4 + and CD8 + T cells in the spleen and lymph nodes. Importantly, the HPLNP demonstrated no systemic toxicity during immunisation. The advantages of the HPLNP, including good biocompatibility, easy preparation, low cost, and its ability to enhance both humoral and cellular immune responses, suggest its suitability as an efficient adjuvant for protein-based vaccines such as HBsAg-VLP. These findings highlight the promising potential of the HPLNP as an HBV vaccine adjuvant, offering an alternative to aluminium adjuvants currently used in vaccines. [ABSTRACT FROM AUTHOR]

The adsorption method for water pollutants has aroused significant attention owing to its convenience, simple operation, high efficiency, and cost-effectiveness. In this paper, a porous organic polymer (POP) namely POP-Por using porphyrin-based and resorcinarene-based molecules as the building block was successfully synthesized via Sonogashira coupling copolymerization, and was then sulfonated to prepare POP-SO3−. POP-Por showed excellent adsorption performance towards bisphenol A (BPA) owing to the high BET surface area and the formation of hydrogen bonding and π–π interactions. The pseudo-second-order rate constant (k2) of POP-Por towards BPA was 12.5 g mg−1 min−1 and the maximum adsorption capacity (Qm) of POP-Por towards BPA was 780 mg g−1. Meanwhile, POP-SO3− exhibited high adsorption affinity towards herbicides including paraquat and diquat due to the strong electrostatic interactions. k2 of POP-SO3− towards paraquat and diquat were 31.4 and 68.6 g mg−1 min−1 (the removal efficiency can reach >96% when the contact time was only 10 s), surpassing those of most of the reported adsorbents. Qm of POP-SO3− towards paraquat and diquat were 237 and 252 mg g−1, respectively, further indicating the excellent adsorption performance of these two POPs. This work provided a smart platform for the construction of POP-based adsorbents to meet the removal demand for pollutants with different charges. [ABSTRACT FROM AUTHOR]

Analysis of drugs clinically and their identification in biological samples are of utmost importance in the process of therapeutic drug monitoring, also in pharmacokinetic investigations and tracking of illicit medications. These investigations are carried out using a variety of analytical methods, including potentiometric electrodes. Potentiometric electrodes are a wonderful solution for researchers because they outperform other methods in terms of sustainability, greenness, and cost effectiveness. In the current study, ion-selective potentiometric sensors were assembled for the aim of quantification of the anticancer drug Letrozole (LTZ). The first step was fabrication of a conventional sensor based on the formation of stable host–guest inclusion complex between the cationic drug and 4-tert-butylcalix-8-arene (TBCAX-8). Two additional sensors were prepared through membrane modification with graphene nanocomposite (GNC) and polyaniline (PANI) nanoparticles. Linear responses of 1.00 × 10–5–1.00 × 10–2, 1.00 × 10–6–1.00 × 10–2 and 1.00 × 10–8–1.00 × 10–3 with sub-Nernstian slopes of 19.90, 20.10 and 20.30 mV/decade were obtained for TBCAX-8, GNC, and PANI sensors; respectively. The developed sensors were successful in determining the drug LTZ in bulk powder and dosage form. PANI modified sensor was used to determine LTZ in human plasma with recoveries ranging from 88.00 to 96.30%. IUPAC recommendations were followed during the evaluation of the electrical performance of the developed sensors. Experimental conditions as temperature and pH were studied and optimized. Analytical Eco-scale and Analytical GREEness metric were adopted as the method greenness assessment tools. [ABSTRACT FROM AUTHOR]

Cryptides are a subfamily of bioactive peptides that exist in all living organisms. They are latently encrypted in their parent sequences and exhibit a wide range of biological activities when decrypted via in vivo or in vitro proteases. Cationic cryptides tend to be drawn to the negatively charged membranes of microbial and cancer cells, causing cell death through various mechanisms. This makes them promising candidates for alternative antimicrobial and anti-cancer therapies, as their mechanism of action is independent of gene mutations. In the current study, we employed an in silico approach to identify novel cationic cryptides with potential antimicrobial and anti-cancer activities in atypical and systematic strategy by reanalysis of a publicly available RNA-seq dataset of Pacific white shrimp (Penaus vannamei) in response to bacterial infection. Out of 12 cryptides identified, five were selected based on their net charges and potential for cell penetration. Following chemical synthesis, the cryptides were assayed in vitro to test for their biological activities. All five cryptides demonstrated a wide range of selective activity against the tested microbial and cancer cells, their anti-biofilm activities against mature biofilms, and their ability to interact with Gram-positive and negative bacterial membranes. Our research provides a framework for a comprehensive analysis of transcriptomes in various organisms to uncover novel bioactive cationic cryptides. This represents a significant step forward in combating the crisis of multi-drug-resistant microbial and cancer cells, as these cryptides neither induce mutations nor are influenced by mutations in the cells they target. [ABSTRACT FROM AUTHOR]

Water filtration is an important application to ensure the accessibility of clean drinking water. As requirements and contaminants vary on a local level, adjustable filter devices and their evaluation with contaminants are required. Within this work, modular filter devices are designed featuring an adjustable surface functionalization. For this purpose, 3D‐printed structures are created consisting of bio‐based poly(lactic acid) (PLA) that are manufactured by extrusion printing. The surface of PLA is activated with amino groups that are used to install xanthates as chain transfer agents. Subsequently, photo‐iniferter (PI) polymerization is used to create cationic polymer brushes on the surface of PLA substrates. Multiple surface characterization techniques are employed to prove successful growth of polymer brushes on PLA. After initial optimization studies on flat surfaces, filter devices are printed, functionalized, and used to remove bacteria from contaminated water. Significant reduction of the number of microorganisms is detected after filtration (single filtration or cycling) and contaminating organism can also be removed from freshwater samples by simple incubation with a 3D‐printed filter. The herein developed setup for producing functional filter devices and probing their performance in affinity filtration is a useful platform technology, enabling the rapid testing of polymer brushes for such applications. [ABSTRACT FROM AUTHOR]

Presently, targeted gene mutagenesis attracts increasing attention both in plant research and crop improvement. In these approaches, successes are largely dependent on the efficiency of the delivery of gene editing components into plant cells. Here, we report the optimization of the cationic polymer poly(2-hydroxypropylene imine) (PHPI)-mediated delivery of plasmid DNAs, or single-stranded oligonucleotides labelled with Cyanine3 (Cy3) or 6-Carboxyfluorescein (6-FAM)-fluorescent dyes into maize protoplasts. Co-delivery of the GFP-expressing plasmid and the Cy3-conjugated oligonucleotides has resulted in the cytoplasmic and nuclear accumulation of the green fluorescent protein and a preferential nuclear localization of oligonucleotides. We show the application of nanoparticle complexes, i.e., "polyplexes" that comprise cationic polymers and nucleic acids, for CRISPR/Cas9 editing of maize cells. Knocking out the functional EGFP gene in transgenic maize protoplasts was achieved through the co-delivery of plasmids encoding components of the editing factors Cas9 (pFGC-pcoCas9) and gRNA (pZmU3-gRNA) after complexing with a cationic polymer (PHPI). Several edited microcalli were identified based on the lack of a GFP fluorescence signal. Multi-base and single-base deletions in the EGFP gene were confirmed using Sanger sequencing. The presented results support the use of the PHPI cationic polymer in plant protoplast-mediated genome editing approaches. [ABSTRACT FROM AUTHOR]

• SNSP113 significantly improved MCT in a Scnn1b-Tg mouse model of mucus stasis. • SNSP113 corrected MCT independent of airway hydration in Scnn1b-Tg mice. • SNSP113 reduced and epithelial hypertrophy in Scnn1b-Tg mice. • SNSP113 reduced incidence of eosinophilic crystalline pneumonia in Scnn1b-Tg mice. • SNSP113 and other agents may have beneficial effects in diseases mucus stasis associated with malformation of mucins. Mucus stasis, a hallmark of muco-obstructive disease, results from impaired mucociliary transport and leads to lung function decline and chronic infection. Although therapeutics that target mucus stasis in the airway, such as hypertonic saline or rhDNAse, show some therapeutic benefit, they do not address the underlying electrostatic defect apparent in mucins in CF and related conditions. We have previously shown poly (acetyl, arginyl) glucosamine (PAAG, developed as SNSP113), a soluble, cationic polymer, significantly improves mucociliary transport in a rat model of CF by normalizing the charge defects of CF mucin. Here, we report efficacy in the CFTR-sufficient, ENaC hyperactive, Scnn1b-Tg mouse model that develops airway muco-obstruction due to sodium hyperabsorption and airway dehydration. Scnn1b-Tg mice were treated with either 250 µg/mL SNSP113 or vehicle control (1.38% glycerol in PBS) via nebulization once daily for 7 days and then euthanized for analysis. Micro-Optical Coherence Tomography-based evaluation of excised mouse trachea was used to determine the effect on the functional microanatomy. Tissue analysis was performed by routine histopathology. Nebulized treatment of SNSP113 significantly improved mucociliary transport in the airways of Scnn1b-Tg mice, without altering the airway surface or periciliary liquid layer. In addition, SNSP113 significantly reversed epithelial hypertrophy and goblet cell metaplasia. Finally, SNSP113 significantly ameliorated eosinophilic crystalline pneumonia and lung consolidation in addition to inflammatory macrophage influx in this model. Overall, this study extends the efficacy of SNSP113 as a potential therapeutic to alleviate mucus stasis in muco-obstructive diseases in CF and potentially in related conditions. [ABSTRACT FROM AUTHOR]

A new method to fabricate carbon nanotube/epoxy composites, consisting of well dispersed and highly concentrated CNTs in an epoxy resin, has been developed. In this method, multiwalled carbon nanotubes (MWNTs) were dispersed into water with the assistance of cationic polymers to form a MWNT sheet by filtration. An epoxy resin was impregnated into the MWNT sheet by vacuum assisted impregnation using a filtration system, followed by autoclave cure, resulting in a MWNT/epoxy composite with a MWNT content of 33 wt%. It was revealed that the composite has a tensile modulus of 8.37 GPa and a tensile strength of 130 MPa. An application of a UV ozone (UV/O3) treatment to the MWNTs increased the XPS O/C ratio from 0.03 to 0.10, resulting in the improvement of the tensile strength to 171 MPa. These results indicate the effectiveness of the UV/O3 treated MWTNs for mechanical property enhancement. [ABSTRACT FROM AUTHOR]

In this study, PVA/p(HEMA-co-MAPTAC) hydrogels were synthesized by redox polymerization using polyvinyl alcohol (PVA), 2-hydroxyethyl methacrylate (HEMA) and [3-(Methacryloylamino)propyl]trimethylammonium chloride (MAPTAC). In order to increase the antimicrobial activities of synthesized PVA/p(HEMA-co-MAPTAC) hydrogels, they were modified with Au nanoparticles. The swelling behavior of the synthesized hydrogels was investigated. Hydrogels were characterized by various techniques. The drug release studies of PVA/p(HEMA-co-MAPTAC) and PVA/p(HEMA-co-MAPTAC)@Au hydrogels were performed in PBS medium using Ribonucleic acid (RNA) as genetic material and sodium diclofenac (NaDc) as drug. It was determined that PVA/p(HEMA-co-MAPTAC) hydrogel held 91.5 mg/g RNA and 97.48 mg/g NaDc and released 28.32 mg/g RNA and 71.12 mg/g NaDc in PBS medium. Subsequently, PVA/p(HEMA-co-MAPTAC)@Au hydrogel adsorbed 87.46 mg/g RNA and 119.44 mg/g NaDc and released 18.96 mg/g RNA, 104.99 mg/g NaDc drug in PBS medium. Using the data obtained at the end of the release studies, the drug release kinetics of the hydrogels were examined. According to the Korsmeyer Peppas model, RNA release from hydrogels showed Fickian diffusion, while NaDc release showed non-Fickian diffusion behavior. The antibacterial and antifungal activities of the hydrogels were tested using gram-negative bacteria E. coli, gram-positive bacteria B. subtilis and a fungus species C. albicans. [ABSTRACT FROM AUTHOR]

Mineral fillers can be added to thermoset polymers to improve thermal conductivity and deformation behavior, shrinkage, impact strength, dimensional stability and molding cycle time. This study aims to prepare various hybrid composites (MFHCs) using melamine formaldehyde foam (MF), a melamine formaldehyde organo-clay nanocomposite (MFNC) and also pumice as primary filler, and gypsum, kaolinite and a hollow glass sphere as secondary filler. It also focuses on the study of some mechanical properties and thermal conductivities, as well as their microscopic and spectroscopic characterization. For this, firstly, organo-clay was prepared with the solution intercalation method using montmorillonite, a cationic surfactant and long-chain hydrocarbon material, and then was produced using a melamine formaldehyde nanocomposite with in situ synthesis using a melamine formaldehyde pre-polymer and organo-clay. Finally, hybrid composites were prepared by blending various minerals and the produced nanocomposite. For morphological and textural characterization, both FTIR spectroscopy and XRD spectra, as well as SEM and HRTEM images of the raw montmorillonite (MMT), organo-montmorillonite (OMMT), pure polymer (MF) and prepared hybrid composites, were used. Spectroscopic and microscopic analyses have shown that materials with different textural arrangements and properties are obtained depending on effective adhesion interactions between polymer–clay nanocomposite particles and filler grains. Mechanical and thermal conductivity test results showed that melamine-formaldehyde-organo-clay nanocomposite foam (MFCNC) exhibited a very good thermal insulation performance despite its weak mechanical strength (λ: 0.0640 W/m K). On the other hand, among hybrid composites, it has been determined that the hybrid composite containing hollow glass beads (MFCPHHC) is a material with superior properties in terms of thermal insulation and mechanical strength (λ: 0.642 W/m K, bulk density: 0.36 g/cm3, bending strength: 228.41 Mpa, modulus of elasticity: 2.22 Mpa and screw holding resistance: 3.59 N/mm2). [ABSTRACT FROM AUTHOR]

Due to the presence of highly persistent and non-biodegradable dyes that are capable of causing harm to people, plants, animals, and the environment, the treatment of dye-contaminated water tends to be highly challenging. In the current work, polyacrylic acid and bio-polymer-based hydrogels of hydroxyl ethyl cellulose (HEC) were prepared through the free radical polymerization method and were used as adsorbents for the adsorption of methylene blue (MB). To estimate the nature and mechanism of adsorption, kinetics, and isotherm models were adopted. Pseudo-second-order kinetic model was followed by the sorption of MB. Results demonstrated that with an increase in concentration of dye dosage, adsorption increases linearly. Freundlich isotherm model was followed for the sorption of MB onto polyacrylic acid and bio-polymer-based hydrogels. Thermodynamic study of the adsorption process reveals that the adsorption process was spontaneous and endothermic as inferred from Gibbs free energy and enthalpy values of 33.08 kJ/mol and 3.83 kJ/mol at 303K, respectively. Recycling performance was tested and inferred that bio-polymer-based hydrogel having 0.6 gm. Hydroxyethyl cellulose decreases its adsorption efficiency equivalent to 5% after consecutive five cycles. The bio-polymer-based hydrogels will be used as an effective adsorbent for removing cationic dyes from wastewater on an industrial scale. [ABSTRACT FROM AUTHOR]

Non-viral chemical-based methods for in vitro cell transfection are commonly used to incorporate foreign gene of interest into mammalian cells due to numerous benefits - high efficiency, low cost and simple methodology. These powerful transfection methods generally do not possess safety risks as virus-based, and cell toxicity is significantly reduced. To obtain transfectants, host cells are usually treated with biocompatible DNA carriers such as calcium phosphate, cationic lipids, DEAE-dextran, polyethylenimine or dendrimers, classifying these methods based on chemical reagents used. All these different approaches are based on the similar principle, namely formation of encapsulated amphiphilic complexes between DNA and various particles, following cell uptake, most likely mediated by endocytosis. Depending on the aim and design of experiment, the choice of appropriate method is made. This review article outlines strategies of the most widely used chemical transfection techniques, pointing out advantages and limitations of different DNA carriers, also findings of researchers as how to optimize and enhance efficiency of gene delivery procedure. With methodology constantly being improved, transfection methods described here find their main, biomedical application in gene therapy, a promising way to introduce functional copy of exogenous gene to genetically defective target cells. [ABSTRACT FROM AUTHOR]

Water-soluble polymers (WSPs) are a class of high-molecular-weight compounds which are widely used in several applications, including water treatment, food processing, and pharmaceuticals. Therefore, they pose a potential threat for water resources and aquatic ecosystems. We assessed the ecotoxicity of four WSPs-non-ionic polyacrylamide (PAM) and polyethylene glycol (PEG-200), anionic homopolymer of acrylic acid (P-AA), and cationic polyquaternium-6 (PQ-6)-as single compounds and in mixture. For this purpose in vitro and in vivo assays were used to record baseline toxicity, mutagenic potential, endocrine effects, and growth inhibition in the freshwater alga Raphidocelis subcapitata. Furthermore, the mixture toxicity of the two polymers P-AA and PQ-6 which showed effects in the algae tests was evaluated with the concentration addition (CA), independent action (IA), and generalized concentration addition (GCA) model and compared with experimental data. No toxic effects were observed among the polymers and their mixtures in the in vitro assays. On the contrary, in the growth inhibition test with R. subcapitata the cationic PQ-6 caused high inhibition while the anionic P-AA and its mixture with the cationic polymer caused low inhibition. The non-ionic polymers PEG-200 and PAM showed no effect in R. subcapitata in the tested concentration range up to 100 mg/L. The IA model represented the mixture effect of the combination experiment better than the CA and GCA models. The results indicate (1) that the toxic effects of anionic and cationic polymers are most likely due to interactions of the polymers with the surfaces of organisms or with nutrients in the water and (2) that the polymers elicit their effects through different mechanisms of action that do not interact with each other. [ABSTRACT FROM AUTHOR]

A novel trimeric cationic surfactant (TEC) has been investigated to use as a hydraulic fracturing fluid thickener with thermal stability. TEC was synthesized with trimethylolpropane triglycidyl ether, erucamidopropyl dimethylamine and hydrochloric acid at 50.0 °C for 7.0 h. The product was compounded with potassium chloride (KCl) for an optimized formulation to form viscoelastic micelles with high-temperature resistance. The apparent viscosity of 5.0 wt%TEC/1.2 wt%KCl fluid remains 23.1 mPa·s after shearing for 90.0 min at 160.0 °C and 100.0 s−1. Three-dimensional (3 D) networks formed by entangled worm-like micelles (WLMs) were observed by an environmental scanning electron microscope. The TEC/KCl solution has a simple formulation and excellent rheological properties, which enriches the viscoelastic surfactant (VES) fracturing fluid class with high-temperature resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] Gene delivery for non-small-cell lung cancer treatment has been a challenge due to low nucleic acid binding ability, cell-wall barrier, and high cytotoxicity. Cationic polymers, such as the traditional "golden standard" polyethyleneimine (PEI) 25 kDa have emerged as a promising carrier for non-coding RNA delivery. However, the high cytotoxicity associated with its high molecular weight has limited its application in gene delivery. To address this limitation, herein, we designed a novel delivery system using fluorine-modified polyethyleneimine (PEI) 1.8 kDa for microRNA-942-5p-sponges non-coding RNA delivery. Compared to PEI 25 kDa, this novel gene delivery system demonstrated an approximately six-fold enhancement in endocytosis capability and maintain a higher cell viability. In vivo studies also showed good biosafety and anti-tumor effects, attribute to the positive charge of PEI and the hydrophobic and oleophobic properties of the fluorine-modified group. This study provides an effective gene delivery system for non-small-cell lung cancer treatment. [ABSTRACT FROM AUTHOR]

The temperature stability and temperature stability range of barium titanate-based pulse energy-storage ceramics were modified by Bi 2 O 3 tailoring in (Ba 0.98- x Li 0.02 Bi x) (Mg 0·04 Ti 0.96)O 3 (x = 0, 0.025, 0.05, 0.075, 0.1) and (Ba 1.03-1.5 x Li 0.02 Bi x) (Mg 0·04 Ti 0.96)O 3 (x = 0.125, 0.15, 0.2, 0.25) ceramics. Excellent pulse energy-storage performances of ceramic films are achieved via the new dual priority strategy of establishing cationic vacancies and forming a liquid phase. The dielectric constant plateau appears due to the cubic phase and space charges. Outstanding temperature stability, frequency stability and antifatigue performance are obtained in the ceramics, and their variations are all less than 15%. The comprehensive energy-storage properties with dual priority parameters of energy-storage density and efficiency of 3.13 J/cm3 and 91.71%, accompanied by an excellent pulse discharge energy density of 2.48 J/cm3, current density of 1313.23 A/cm2 and power density of 195.26 MW/cm3 are gained at x = 0.1. The perfect pulse energy-storage performances as well as ultrahigh stability are correlated with synergistic effects of multiphase coexistence, cubic phase, liquid-phase sintering, grain size, ceramic resistance, space charges and polar nanoregions. The comprehensive parameters indicate that the (Ba 0·88 Li 0·02 Bi 0.1) (Mg 0·04 Ti 0.96)O 3 ceramics have potential application in high precision fields. [ABSTRACT FROM AUTHOR]

Abnormally high level of cell-free DNA (cfDNA) is one of the important causes of autoimmune diseases, which aggravate the symptoms of rheumatoid arthritis (RA). Recently, the utilization of cationic polymeric nanoparticles for scavenging cfDNA has emerged as a promising therapeutic strategy for the treatment of RA. However, the intravenous introduction of cationic polymeric nanoparticles into the circulation carries a risk of dissociation, causing toxicity. To realize the potential clinical translation, we employed a series of silica particles grafted with poly(2-(dimethylamino) ethyl methacrylate) (PDMA) (SiNP@PDMA) brush, which possess adjustable PDMA content (100, 200, and 300 degree of polymerization (DP)) and particle size (50, 100, and 200 nm diameter), to selectively scavenge cfDNA in inflamed joint cavity. We demonstrate that the binding affinity for cfDNA, cytotoxicity, circulation time in vivo and retention in the inflamed joint cavity are influenced by the core-shell structure of SiNP@PDMA, ultimately impacting therapeutic efficacy. Among them, SiNP@PDMA with 100 nm size and 200 DP of PDMA exhibit enhanced accumulation and prolonged retention time in inflammatory joint cavity, resulting in superior therapeutic effect. Therefore, in this study, applying the precisely tuning size and cation content of SiNP@PDMA, we demonstrated the factors to matter the therapeutic effect of cationic nanoparticles, which deepened the understanding of the anti-inflammatory therapies based on cfDNA scavenger for RA. Inspired by the discovery that cfDNA would induce inappropriate immune responses to exacerbate the progress of RA, we innovatively employed SiNP@PDMA as a cfDNA scavenger to inhibit cfDNA-induced inflammation in RA. Increase in the cation content efficiently strengthened the binding between SiNP@PDMA and cfDNA, leading to an improvement in inhibitory effect of inflammation. In addition, we compared the behaviors of 50, 100 and 200 nm SiNP@PDMA in RA symptom suppression, local cfDNA scavenging and inflammation inhibition. The results demonstrated that SiNP 100 -PDMA 200 outperformed other analogues, corresponding to their more favorable distribution in inflammatory articular cavity. Together, this study revealed the structure-property relationship of cfDNA scavengers for further development of safe and effective cfDNA scavenging system. [Display omitted] [ABSTRACT FROM AUTHOR]

Gemini surfactants, composed of two surfactant monomers, are likely to self-assemble into viscoelastic fluids in water at low concentrations. Here, the aggregation behaviors of quaternary ammonium gemini surfactant with a hydroxyl group on the spacer (16-3OH-16) have been studied in the dilute aqueous system by rheological techniques, small angle X-ray scattering (SAXS), scanning electron microscopy (SEM) and other characterizations. At room temperature, the samples behave as elastic gels. The structure and morphology of gels were confirmed by SAXS and SEM characterizations. Due to the hydroxyl group on the spacer of 16-3OH-16, the gels are more stable than those formed by 16-3-16. At high temperature, the gels transform into wormlike micelles and behave as viscoelastic fluids. The obtained results would help to construct complexed fluids with structure tailorable gemini surfactants. The elastic Lβ gel showing good thixotropic behavior was constructed by the cationic gemini surfactant 16-3OH-16 with a hydroxyl group on the spacer. The alkyl chains of 16-3OH-16 would cross to form the hydrophobic domains while water could be confined in the solvent layer. [ABSTRACT FROM AUTHOR]

Applications of haloalkane dehalogenase DhaA in biocatalysis are limited by its unfavorable performance in organic solvents. Our previous work proved that mutations of surface positive-charged residues enhanced the organic solvent resistance of DhaA, which inspired us to explore the effect of cationic polymers on DhaA in organic solvents. Remarkably boosted performance was achieved in different organic solvent solutions by introducing cationic polymers, for example, there was a 6.1-fold activity increase with poly(allylamine hydrochloride) and a 5.5-fold activity increase with poly(ethylene imine) in 40 vol.% dimethylsulfoxide. The presence of cationic polymers protected DhaA from damage by organic solvents and increased the substrate concentration around the enzyme-polymer complex. Fluorescence spectroscopy and molecular dynamics simulations revealed that the binding of cationic polymers onto DhaA weakened the interactions between organic solvents and DhaA, decreased the organic solvent solvation level around DhaA, and enhanced the structural stability of DhaA in organic solvents. This comprehensive understanding of the effect of cationic polymers on DhaA can help to broaden the applications of DhaA in organic solvent-involved biocatalysis. [ABSTRACT FROM AUTHOR]

Biocidal coatings have been used in biomedicine, cosmetology and the food industry. In this article, the coatings are described as being composed of non-stoichiometric polycomplexes, products of electrostatic coupling of two commercial biodegradable ionic polymers, anionic sodium alginate and cationic quaternized hydroxyethyl cellulose ethoxylate. Non-stoichiometric polycomplexes with a 5-fold excess of the cationic polymer were used for immobilizing hydrophobic biocidal 4-hexylresorcinol (HR). Being dispersed in water, the polycomplex particles were capable of absorbing a tenfold excess of HR in relation to the polycation. After deposition onto the plastic surface and drying, the aqueous polycomplex–HR composite formulation forms a transparent homogeneous coating, which swells slightly in water. The interpolyelectrolyte complex (IPEC) is substantially non-toxic. The incorporation of HR in the IPEC imparts antimicrobial activity to the resulting composite, in both aqueous solutions and coatings, against Gram-negative and Gram-positive bacteria and yeast. The polysaccharide-based polycomplexes with embedded HR are promising for the fabrication of biocidal films and coatings. [ABSTRACT FROM AUTHOR]

MXene has become one of the most sought-after 2D materials with incredible potential in various fields. This work reports the use of a cationic polymer polyethyleneimine (PEI) to generate a positive charge on the MXene surface. PEI is a positively charged polymer containing repeating amine groups. PEI functionalized MXene nanoflakes (PEI_Ti3C2) were produced by etching Ti3AlC2, followed by ultrasonication along with PEI, and then hydrothermally treated at 200 °C for 24 h. The as-obtained nanosheets were characterized through XRD, AFM, TEM, UV–Vis spectroscopy, PL, and FTIR. The thickness of PEI_Ti3C2 was found to be 2.6 ± 0.8 nm compared to control (h-Ti3C2) which exhibited 6.8 ± 1.6 nm height, proving utilization of PEI both as a surfactant as well as a functionalizing agent. The surface charge of PEI_Ti3C2 sheets was observed to be 15.57 ± 2.76 mV due to the presence of imine groups. Colloidal solution of PEI_Ti3C2 displayed high absorption in both the UV (315–600 nm) and NIR ranges (880–996 nm) as well as exhibits blue fluorescence. The use of the PEI polymer also assists in MXene forming a stable aqueous dispersion. PEI_Ti3C2 showed high biocompatibility in mouse fibroblast and red blood cells. On the other hand, the nanosheets demonstrated concentration-dependent cellular toxicity on cancer cells when irradiated with 808 nm laser irradiation for 10 min. The small-sized PEI_Ti3C2 are highly scalable, reproducible, biocompatible, possess intrinsic NIR activity, fluorescence, and cationic character. The NIR activity and photoluminescence of the 2D nanosheets make them multifaceted to be utilized as cell labeling probes, sensors, and photothermal therapy. [ABSTRACT FROM AUTHOR]

Polyethlyenimine (PEI) was introduced 1995 as a cationic polymer for nucleic acid delivery. PEI and its derivatives are extensively used in basic research and as reference formulations in the field of polymer-based gene delivery. Despite its widespread use, the number of clinical applications to date is limited. Thus, this review aims to consolidate the past applications of PEI in DNA delivery, elucidate the obstacles that hinder its transition to clinical use, and highlight potential prospects for novel iterations of PEI derivatives. The present review article is divided into three sections. The first section examines the mechanism of action employed by PEI, examining fundamental aspects of cellular delivery including uptake mechanisms, release from endosomes, and transport into the cell nucleus, along with potential strategies for enhancing these delivery phases. Moreover, an in-depth analysis is conducted concerning the mechanism underlying cellular toxicity, accompanied with approaches to overcome this major challenge. The second part is devoted to the in vivo performance of PEI and its application in various therapeutic indications. While systemic administration has proven to be challenging, alternative localized delivery routes hold promise, such as treatment of solid tumors, application as a vaccine, or serving as a therapeutic agent for pulmonary delivery. In the last section, the outcome of completed and ongoing clinical trials is summarized. Finally, an expert opinion is provided on the potential of PEI and its future applications. PEI-based formulations for nucleic acid delivery have a promising potential, it will be an important task for the years to come to introduce innovations that address PEI-associated shortcomings by introducing well-designed PEI formulations in combination with an appropriate route of administration. [Display omitted] • PEI was introduced 1985 as a cationic polymer for nucleic delivery. • PEI-based research has provided a wealth of pre-clinical data. • Challenges associated with the use of PEI are analyzed. • A comprehensive analysis of clinical trials is provided. • New generations of PEI-derivatives offer interesting options. [ABSTRACT FROM AUTHOR]

[Display omitted] The conventional deposition/drying procedure results in the formation of cationic polymer coatings on glass slides that are capable of binding bacterial and yeast cells. A three-minute water treatment removes up to 80% of cells from the surface, and both the removed and remaining cells are dead. The results obtained clarify the mechanism of the biocidal action of adsorbed layers of poly(diallyldimethylammonium chloride) and the protocol for quantifying their biocidal activity. [ABSTRACT FROM AUTHOR]

[Display omitted] Negatively charged polycomplexes have been prepared by electrostatic complexation of synthetic cationic poly(diallyldimethylammonium chloride) with excess anionic sodium alginate. These polycomplexes exhibit pronounced antimicrobial activity due to the biodegradation of the alginate matrix and the release of the biocidal polycation. The results obtained are promising for the development of simultaneously attractive and toxic polymer constructs capable of destroying microorganisms. [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.

The development of antibacterial coatings is a promising approach to preventing biofilm formation and reducing the overuse of systemic antibiotics. However, widespread antibiotic use has resulted in antibiotic‐resistant bacteria, limiting the efficacy of antibiotic‐based coatings. Herein, an antibacterial coating is developed by layer‐by‐layer (LbL) assembly of two polymers namely PDLG (poly (D,L‐lactide‐co‐glycolide)) and gelatin methacryloyl (GelMA) while chicken cathelicidin‐2 (CATH‐2), a cationic and amphipathic peptide, is loaded between these polymer layers. The electrospray method is used to apply the coatings to achieve efficient peptide loading and durability. The CATH‐2 bactericidal concentration ranges are first identified, followed by a study of their cytotoxicity to human mesenchymal stem cells (hMSCs) and macrophage cell lines. Later, different LbL electrospray coating assemblies loaded with the optimal peptide concentration are sought. Various coating strategies are investigated to identify an LbL coating that exhibits prolonged and biocompatible CATH‐2 release. The resulting CATH‐2‐coated titanium surfaces exhibit strong antibacterial activity against both Staphylococcus aureus and Escherichia coli bacteria for 4 days and are biocompatible with hMSCs and macrophage cells. This coating can be considered as a versatile delivery system platform for the delivery of CATH‐2 peptides while avoiding cytotoxicity, particularly for the prevention of infections associated with implants. [ABSTRACT FROM AUTHOR]

Despite the enormous interest in high-areal-capacity Li battery electrodes, their structural instability and nonuniform charge transfer have plagued practical application. Herein, we present a cationic semi-interpenetrating polymer network (c-IPN) binder strategy, with a focus on the regulation of electrostatic phenomena in electrodes. Compared to conventional neutral linear binders, the c-IPN suppresses solvent-drying-induced crack evolution of electrodes and improves the dispersion state of electrode components owing to its surface charge-driven electrostatic repulsion and mechanical toughness. The c-IPN immobilizes anions of liquid electrolytes inside the electrodes via electrostatic attraction, thereby facilitating Li+ conduction and forming stable cathode–electrolyte interphases. Consequently, the c-IPN enables high-areal-capacity (up to 20 mAh cm–2) cathodes with decent cyclability (capacity retention after 100 cycles = 82%) using commercial slurry-cast electrode fabrication, while fully utilizing the theoretical specific capacity of LiNi0.8Co0.1Mn0.1O2. Further, coupling of the c-IPN cathodes with Li-metal anodes yields double-stacked pouch-type cells with high energy content at 25 °C (376 Wh kgcell−1/1043 Wh Lcell–1, estimated including packaging substances), demonstrating practical viability of the c-IPN binder for scalable high-areal-capacity electrodes. Binders employed in battery electrodes are conventionally neutral linear polymers. Here, authors present a cationic semi-interpenetrating polymer network binder to regulate electrostatic phenomena, improving the properties and performance of high-capacity positive electrodes for Li metal batteries. [ABSTRACT FROM AUTHOR]

Due to the low energy density of commercial printable dielectrics, printed capacitors occupy a significant printing area and weight in printed electronics. It has long remained challenging to develop novel dielectric materials with printability and high‐energy storage density. Herein, a novel strategy for inkjet printing of all aqueous colloidal inks to dielectric capacitors composed of carbon nanotube electrodes and polyvinylidene fluoride (PVDF)‐based dielectrics is presented. The formulated dielectric ink is composed of negatively charged PVDF latex nanoparticles complexed with cationic chitosan molecules. Beyond the isoelectric point, the PVDF@Chitosan particles demonstrate excellent printability and film‐forming properties. Chitosan serves as a strong binder to improve the printed film quality yet it introduces charged species. To mitigate the transport of mobile charges, the printed PVDF@Chitosan film is interlayered with a layer of boron nitride nanosheets. This layer is perpendicular to the electric field and serves as an efficient barrier to block the transport and the avalanche of charges, eventually leading to a recoverable energy density of 15 J cm−3 at 610 MV m−1. This energy density represents the highest value among the waterborne dielectrics. It is also superior to most of the state‐of‐the‐art dielectric materials printed from solvent‐based formulations. [ABSTRACT FROM AUTHOR]

Dendrite growth on electrode‐electrolyte interphase has severely limited applications of lithium metal batteries (LMBs). Here, we developed an ionic alternating polymer with fluorocarbons and phosphonium cations in repeating units to regulate Li deposition for the first time. The combined functionalities in the F/P hybrid polymer exhibit remarkable characteristics as a protective layer on top of Li anode, demonstrating outstanding electrochemical stability, ion flux redistributing capability and adaptive chain mobility. Based on characterizations and simulations, this cationic interlayer could effectively furnish long‐standing electrostatic shielding for anodes, allowing restrained coating decomposition and homogenized electric field distribution to induce dendrite‐free Li deposition, and enabling full cells with enhanced rate and long‐term cycling performance. Given the importance of LMBs, this work will promote polymer design to stabilize anodes with superior electrochemical behavior. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrogen reduction reaction offers a sustainable alternative to the conventional Haber‐Bosch process. However, it is currently restricted by low effective overpotential due to the concentration polarization, which arises from accumulated products, ammonium, at the reaction interface. Here, a novel covalent organic polymer with ordered periodic cationic sites is proposed to tackle this challenge. The whole network exhibits strong positive charge and effectively repels the positively charged ammonium, enabling an ultra‐low interfacial product concentration, and successfully driving the reaction equilibrium to the forward direction. With the given potential unchanged, the suppressed overpotential can be much liberated, ultimately leading to a continuous high‐level reaction rate. As expected, when this tailored microenvironment is coupled with a transition metal‐based catalyst, a 24‐fold improvement is generated in the Faradaic efficiency (73.74 %) as compared with the bare one. The proposed strategy underscores the importance of optimizing dynamic processes as a means of improving overall performance in electrochemical syntheses. [ABSTRACT FROM AUTHOR]

The protein Beclin1 (BECN1, a mammalian homologue of ATG6 in yeast) plays an important role in the initiation and the normal process of autophagy in cells. Moreover, we and others have shown that Beclin1 plays an important role in viral replication and the innate immune signaling pathways. We previously used the cationic polymer polyethyleneimine (PEI) conjugated to mannose (Man) as a non-viral tool for the delivery of a small interfering (si) Beclin1-PEI-Man nanoplex, which specifically targets mannose receptor-expressing glia (microglia and astrocytes) in the brain when administered intranasally to conventional mice. To expand our previous reports, first we used C57BL/6J mice infected with EcoHIV and exposed them to combined antiretroviral therapy (cART). We show that EcoHIV enters the mouse brain, while intranasal delivery of the nanocomplex significantly reduces the secretion of HIV-induced inflammatory molecules and downregulates the expression of the transcription factor nuclear factor (NF)-kB. Since a spectrum of neurocognitive and motor problems can develop in people living with HIV (PLWH) despite suppressive antiretroviral therapy, we subsequently measured the role of Beclin1 in locomotor activities using EcoHIV-infected BECN1 knockout mice exposed to cART. Viral replication and cytokine secretion were reduced in the postmortem brains recovered from EcoHIV-infected Becn1+/− mice when compared to EcoHIV-infected Becn1+/+ mice, although the impairment in locomotor activities based on muscle strength were comparable. This further highlights the importance of Beclin1 in the regulation of HIV replication and in viral-induced cytokine secretion but not in HIV-induced locomotor impairments. Moreover, the cause of HIV-induced locomotor impairments remains speculative, as we show that this may not be entirely due to viral load and/or HIV-induced inflammatory cytokines. [ABSTRACT FROM AUTHOR]