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The low penetration of antibacterial materials within biofilms results in a 1000‐fold decrease in bactericidal efficiency, complicating the complete removal of biofilms and potentially leading to persistent and recurrent bacterial infections that significantly impact human health. In this study, we present a multifunctional pH‐responsive antibacterial material based on random copolymers poly(dimethylaminoethyl methacrylate decyl ammonium bromide‐co‐polyethylene glycol methacrylate) copolymer (PQACs10‐co‐PEGMA10). The PQACs10‐co‐PEGMA10 copolymers could self‐assemble into micelles in selective solvent water. With the stealth function of polyethylene glycol (PEG), the PQACs10‐co‐PEGMA10 micelles can rapidly penetrate biofilms in a physiological environment and exhibit excellent antibacterial activity by exposing the quaternary ammonium salt (QACs) in an acidic microenvironment to eliminate biofilm. Furthermore, PQACs10‐co‐PEGMA10 micelles were applied as coatings using a dropwise method. The PEG chain formed hydration layer and the QACs chain for sterilization can hinders bacterial adhesion and proliferation, thereby preventing biofilm formation. The results show that the minimal inhibit concentration values and minimum biofilm eradication concentrations of the PQACs10‐co‐PEGMA10 micelles against Gram‐positive Staphylococcus aureus were 64 and 128 μg/mL, respectively. The antifouling and antibacterial rates of micelle coating against S. aureus were more than 99.99%. Taken together, the pH‐responsive PQACs10‐co‐PEGMA10 micelles demonstrate a good ability to clear and prevent biofilms, holding promise for complete biofilm removal and a reduction in biofilm‐related infections. [ABSTRACT FROM AUTHOR]

AbstractResearch focus has turned to sustainable and ecologically friendly energy sources due to the growing dependence on nonrenewable fuels. The lignocellulosic biomass’s (LCB) intrinsic recalcitrance makes the bioprocess’s downstream processing difficult. Over the past 20 years, pretreatment procedures have drawn a lot of attention since they are acknowledged as essential operations for effective biomass refining. In order to achieve more sustainable practices, deep eutectic solvents (DESs) are proven to be useful for LCB valorization. DESs are thermochemically stable, recyclable, non-flammable, and contain very little vapor pressure. In the present article, an extensive summarization of the types, characteristics, and functions of DESs in the efficient conversion of sugarcane bagasse is reviewed. In addition to outlining the principles of DES composition, an overview is provided on the factors influencing the ChCl-DES-assisted extraction of the compositional components from sugarcane bagasse. Furthermore, an in-depth insight into the mechanism behind the ChCl-based-DES reactions on sugarcane bagasse will provide useful highlights for future studies. The most recent advancements for the years 2018–2023 on the DES-based valorization of sugarcane bagasse into various products are then thoroughly covered. Finally, the paper is concluded with a discussion of the technical issues and potential directions for the future research works. [ABSTRACT FROM AUTHOR]

Safety issues of lithium metal batteries caused by leakageable, inflammable, and unstable electrolytes and lithium dendrites are a major concern worldwide. Herein, an ultra‐concentrated electrolyte composed of 85.3 wt.% of a novel phosphate quaternary ammonium lithium salt (PQ‐3Li) in fluoroethylene carbonate is prepared, labeled as CPQE. CPQE reveals an exceptional ionic conductivity (0.32 × 10−3 S cm−1), a high lithium transference number (0.66), an electrochemical stability window above 6 V, and a superb fire resistance. Li|CPQE|Li cells show stable cycling performance without lithium dendrites for 1000 h, and a solid‐electrolyte‐interface layer with an inorganics‐rich inner layer and an organics‐rich outer layer is confirmed using computation simulation, electron probe microanalysis, and X‐ray photoelectron spectroscopy. Li|CPQE|NCM cells present a discharge capacity of 162 mAh g−1 at 0.1 C, and a Coulombic efficiency of up to 99%. A commercial LED bulb can be lighted up by the Li|CPQE|NCM cell for at least 1 h without performance deterioration while prolonging the cycling time. The fabricated CPQE‐based pouch cells own terrific safety and power supply capacity. No leakage, thermal runaway, combustion, or explosion behavior is detected during the nailing penetration test, implying large potential applications for developing the next generation of high‐safety lithium batteries. [ABSTRACT FROM AUTHOR]

The cathode interface material is pivotal for achieving excellent photovoltaic performance and device stability in organic solar cells (OSCs). However, currently, few interface materials can simultaneously satisfy multiple criteria such as low cost, high efficiency, insensitivity to film thickness, and good stability. To address this challenge, a novel perylene diimide (PDI) derivative, P‐C3T is designed and synthesized, by incorporating stable free radical unit TEMPO and polar quaternary ammonium salt as side chains. P‐C3T is facile to synthesize and cost‐effective, while also exhibiting good conductivity and excellent ohmic contact characteristics in OSCs. When utilized as the cathode interface material, the device based on D18:L8‐BO achieves a remarkable power conversion efficiency (PCE) of 19.52%, which is one of the highest levels reported for binary single‐junction OSCs. Notably, devices based on P‐C3T exhibit remarkable insensitivity to film thickness, with the PCE remaining at 95% of the initial efficiency even at a thickness of 40 nm. Furthermore, P‐C3T‐based OSCs demonstrate exceptional storage stability and improved light stability. In summary, with its high PCE, excellent thickness insensitivity, and good stability, P‐C3T is anticipated to be a promising candidate material for large‐area roll‐to‐roll processing of OSCs. [ABSTRACT FROM AUTHOR]

Highly efficient red luminescent organic radicals with less solvent sensitivity are much more attractive due to their wide application in various fields, especially in fluorescence sensing, and bioimaging. In this work, we synthesized a three δ‐carboline‐capped highly efficient propeller‐like organic radical TTM‐3δPyID with a D−A structure. The radical showed pure red emission with PLQY of 77.3 % in cyclohexane and kept 35.2 % even in the polar solvent dichloromethane, indicating potential applications in fluorescence sensing. Radical TTM‐3δPyID also showed stepwise proton‐responsive properties and different emissions at the different states. Furthermore, by taking advantage of the nitrogen site of the radical, we have achieved a fluorescent‐quenched radical derivative TTM‐3δPyID‐AB by introducing of 2‐bromoethyl chain through a quaternary ammonium salt reaction. The radical TTM‐3δPyID‐AB showed turn‐on fluorescence in the presence of primary organic amines. Finally, this turn‐on fluorescent property is successfully used to distinguish aliphatic amines from aromatic amines. [ABSTRACT FROM AUTHOR]

Diesel contamination in water bodies poses a significant environmental challenge due to the toxic effects of its water-soluble fraction (WSF) on aquatic ecosystems and human health. The aim of this work was the design of a new technological procedure for the purification of water contaminated with the WSF of diesel. The procedure is based on the adsorption of organic pollution on an organozeolite, after which the biodegradation of the adsorbed pollutant takes place. The material for obtaining organozeolite was a natural zeolite from the Zlatokop deposit (Vranje, Serbia). The zeolitic surface was modified with hexadecyltrimethylammonium bromide (HDTMA-Br), a cationic quaternary ammonium salt. The adsorption experiments, with initial WSF concentrations of 2.5–25 mg/L, at pH 6 and at 20 °C, were performed in a batch system using organozeolite, and the results showed that more than 90% of the WSF of diesel was removed, reaching equilibrium after 1 h. The maximum adsorbed capacity of organozeolite for the removal of the WSF of diesel fuel from water under the tested conditions was 22.2 mg/g. Equilibrium data were well fitted by a linear isotherm model, while a pseudo-second-order equation well fitted the kinetic data. After adsorption, a 15-day biodegradation experiment was carried out under batch conditions. The results showed that the examined consortium of microorganisms degraded 80% of the adsorbed contaminant. Additional respirometric analyses showed that, in parallel with the degradation of the contaminant, the degradation of the long-chain HDTMA ions at the surface of the organozeolite also occurred. To the best of our knowledge, this is the first study combining adsorption and biodegradation to remove the WSF of diesel from water. [ABSTRACT FROM AUTHOR]

Sol–gel nano‐silica antireflective (AR) coatings with moisture resistance are widely used for optical elements, such as potassium dihydrogen phosphate (KDP) crystals, but their mildew resistance is often disregarded. This work reports a double‐layer AR coating with moisture resistance and mildew resistance for KDP crystals. A polydimethylsiloxane‐modified dense silica coating and a quaternary ammonium salt (QAS) modified nanoporous silica coating are selected as the bottom layer and top layer, which effectively serve as a moisture barrier and an antireflection layer, respectively. The coated KDP crystal shows excellent antireflection properties with a maximum transmittance of 99.1% at 532 nm. Perfluorooctyltriethoxysilane vapor treatment is performed further to improve the resistance to moisture and mildew. The resultant double‐layer coating exhibits superior moisture resistance with almost no change in optical transmittance after a 3‐month exposure to a high‐humidity environment. The introduction of QAS and hydrophobicity in the top layer provides exceptional resistance against mildew, achieving an antimicrobial rate of 99.9% against E. coli and A. flavus. Moreover, the laser‐induced damage threshold reaches 17.0 J cm−2 (355 nm, 4.5 ns). This work imparts moisture resistance and mildew resistance to AR coatings, providing valuable insights for designing multifunctional AR coatings on optical components. [ABSTRACT FROM AUTHOR]

Anion-exchange membranes (AEMs) with high conductivity and stability are essential components of hydrogen related water electrolysis and fuel cell applications. During the past decades, polynorbornene (PNB)-based AEMs have shown excellent performance due to their saturated all-carbon-based backbones and diverse strategies to prepare cross-linked membranes. However, nearly all previously reported PNB-based AEMs rely on the alkyl-substituted norbornene monomers, whose low-yielding synthesis leads to high-cost of the AEMs. In addition, the cross-linked PNB-based AEMs usually suffered from mechanical brittleness. Herein, we propose a novel semi-interpenetrating polymer network (s-IPN) strategy to simultaneously enhance mechanical modulus and ionic conductivity, while using commercial 5-vinyl-2-norbornene (VNB) as the single norbornene derivatives to prepare high-performance AEMs. A diallylphenol quaternary ammonium salt was used for photo-induced cross-linking with poly-VNB and various dithiols to produce AEMs with s-IPN structures. The resultant membranes have excellent hydroxide conductivities and alkaline stability in 1 mol/L KOH at 80 °C, and are successfully applied in alkaline anion-exchange membrane water electrolyzers to stably operate for over 150 h. [ABSTRACT FROM AUTHOR]

The crystal structures of nine hexamethyl‐[1,1′‐biphenyl]‐4,4′‐diammonium (HMB) salts are described: the iodide (2), triiodide (3), succinate (4), fumarate (5), tetravanadate (6), hydroterephthalate (7) and perylenetetracarboxylate (8), as well as pentamethyl‐[1,1′‐biphenyl]‐4,4′‐diammonium iodide (1) and the metal–organic framework sodium diacetylenedisalicylate–HMB (9). HMB carbonate (10) has been synthesized as an important intermediate for a promising anti‐metal–organic framework ('anti‐MOF'). All the described compounds are characterized by high solubility in water. The results suggest that, during crystallization, crystallohydrates are formed from water. Compounds 6 and 9 are characterized by the presence of a rigid framework; compound 6 has an open framework structure filled with water molecules. Synchronous thermal analyses of compounds 2, 4, 6, 7, 8 and 10 allowed the identification of similarities in the mechanisms of thermolysis. At about 80–180°C, the loss of crystallization water molecules occurs. Between 180 and 250°C, a methyl group (methyl cation) is split off from the quaternary ammonium salt to form tetramethylbenzidinium. In the case of the iodides and salts of organic acids, the second thermolysis product is the methyl ester of this acid (methyliodide, dimethyl carbonate), which easily evaporates. In the range 240–355°C, tetramethylbenzidinium evaporates without decomposition. [ABSTRACT FROM AUTHOR]

Objectives: Microbial contamination of various accessory parts of the dental chair units (DCUs) is an essential source of cross infection, while the accessories of the crucial suction function are usually overlooked. In this study, we aim to find an effective disinfectant and a cost-effective method to remove bacterioplankton and bacterial biofilm deposited in the negative pressure suction pipelines to control cross infection during dental treatment. Methods: Double-chain quaternary ammonium salt disinfectant (Orotol Plus®), 3% hydrogen peroxide solution plus multi-enzyme cleaning agent and chlorine disinfectant are used to clean and disinfect the negative pressure pipelines of DCUs. Microbiological examinations, air condition detection, corrosion tests and gene sequencing are performed. Results: Little bacteria grow in the pipelines disinfected with double-chain quaternary ammonium salt disinfectants, destruction of biofilms in these pipelines appears, and multi-resistant bacteria cannot be detected. Minimal damage to metal sheets and fittings is caused by double-chain quaternary ammonium salt disinfectants. Conclusion: Double-chain quaternary ammonium salt disinfectant has excellent bactericidal ability and anti-biofilm effect, and it is less corrosive to the fittings of the pipelines. Thus, the double-chain quaternary ammonium salt disinfectant is a potential novel disinfectant for negative pressure suction pipelines of DCUs to control cross infection during dental treatment. Clinical significance: It is essential to add all these data to our dental practice to control cross infection with a broader landscape. [ABSTRACT FROM AUTHOR]

Surface alkali deweighting is an important link to enhance the added value of polyester (PET) textiles. However, the traditional high-concentration liquid alkali treatment has the problem of high pollution and high risk, which runs counter to cleaner production. To reduce the amount of alkali, quaternary ammonium salt accelerators with different structures were used to improve the alkali deweighting efficiency of polyester fabric. The effects of sodium hydroxide, accelerator dosage, molecular structure of accelerator, and holding time on alkali deweighting of polyester fabric were studied. The mechanism was analyzed based on surface morphology, zeta potential. In addition, the differences, such as hydrophilicity, breaking strength, whiteness, and dyeing properties of pretreated textiles, were further compared. The results showed that the alkali deweighting efficiency of accelerator containing benzyl groups was better than that of the accelerator with same alkyl chain containing methyl groups at the same concentration. Meanwhile, as the hydrophobic chain changes from dodecyl to cetyl, and octadecyl, the deweighting efficiency increased markedly, especially for the accelerator containing benzyl group. The 0.5 g/L of octadecyl dimethyl benzyl ammonium chloride (1827) combined with 10 g/L of sodium hydroxide can save 72.2% of alkali consumption to obtain weight loss rate of 20%. Also, the polyester fabrics treated with accelerators showed good hydrophilicity, breaking strength, and dyeing property compared to conventionally treated polyester fabric with the same weight loss rate. These findings provide a new idea for reducing the amount of alkali effectively and basic dyeing of polyester fabrics. [ABSTRACT FROM AUTHOR]

As exploration and development to the ultra-deep layer continue to advance, bottom hole temperatures have gradually increased, aggravating acid corrosion of the downhole pipe string and greatly challenging the safety of reservoir reconstruction. Hydrochloric acid (HCl), an inorganic acid with strong acidity, is widely used in common acid systems in oil fields. Therefore, the prevention of corrosion by HCl under high temperature is an important task. In this study, we analyze the molecular structure, synergistic effect, and inhibition mechanism of imidazoline, Mannich base, quaternary ammonium salt, and other high-temperature HCl inhibitors and green inhibitors to explore the temperature resistance of inhibitors from the perspective of molecular microstructure and provide guidance for the development of ultra-high-temperature acidification inhibitors. Finally, the advantages and disadvantages of various HCl corrosion inhibitors are compared and summarized, and the knowledge gap and future research direction in the development field of high-temperature HCl corrosion inhibitors are pointed out. [ABSTRACT FROM AUTHOR]

A convenient and safe methylation protocol employing quaternary ammonium salts (PhMe3NI) as alternative methylating agents for the selective α‐methylation of arylacetonitriles is presented. This approach allows for the selective α‐methylation of arylacetonitriles, overcoming the limitations of existing techniques, while offering a practical and sustainable solution for late‐stage functionalization in medicinal chemistry. The straightforward and safe nature of this methodology makes it particularly well‐suited for applications in drug discovery. In our report, we present a diverse set of 18 examples, achieving yields of up to 76 %. [ABSTRACT FROM AUTHOR]

Massive accumulation of postconsumer plastic waste in eco‐system has raised growing environmental concerns. Sustainable end‐of‐life managements of the indispensable plastic are highly demanding and challenging in modern society. To relieve the plastic menace, herein we present a full life cycle sustainable supramolecular bioplastic made from biomass‐derived polyelectrolyte (chitosan quaternary ammonium salt, QCS) and natural sodium fatty acid (sodium laurate, SL) through solid‐phase molecular self‐assembly (SPMSA), by which the QCS‐SL complexes, precipitated from mixing the aqueous solutions, self‐assemble to form bioplastic film by mildly pressing at room temperature. The QCS‐SL bioplastic films display superior hydroplasticity owing to the water‐activated molecular rearrangement and electrostatic bond reconstruction, which allows facile self‐healing and reprocessing at room temperature to significantly extend the service lifetime of both products and raw materials. With higher water content, the dynamic electrostatic interactions and precipitation‐dissolution equilibrium endow the QCS‐SL bioplastic films with considerable solubility in water, which is promising to mitigate the plastic accumulation in aquatic environment. Because both QCS and SL are biocompatible and biodegradable, the dissolved QCS‐SL films are nontoxic and environmentally friendly. Thus, this novel supramolecular bioplastic is highly sustainable throughout the whole life cycle, which is expected to open a new vista in sustainable plastic materials. [ABSTRACT FROM AUTHOR]

[Display omitted] Cationic surfactants have a wide range of applications, often associated with their affinity for a range of solid surfaces and their anti-microbial properties. Manipulating their adsorption and self-assembly properties is key to most applications, and this is commonly achieved through surfactant mixtures or manipulating their headgroup or alkyl chain structure. Achieving this through adjustments to their headgroup structure is less common in cationic surfactants than in anionic surfactants. Ethoxylation provides the ability to adjust the hydrophilic / hydrophobic balance, as extensively demonstrated in a range of anionic surfactants. This same approach has been applied here to a range of ethoxylated cationic surfactants in the form of the quaternary ammonium salts, and their tertiary nonionic equivalents before quaternisation. Their adsorption and self-assembly properties are investigated using predominantly the neutron scattering techniques of neutron reflectivity, NR, and small angle neutron scattering, SANS. The trends in the adsorption at the air–water interface and the self-assembly in aqueous solution demonstrate how the hydrophilic / hydrophobic balance can be adjusted by varying the degree of ethoxylation and the alkyl chain length, and illustrate the degree of interdependence of the different structural changes. The variation in the adsorption and the micelle structure shows how the surfactant conformation / packing changes as the degree of ethoxylation and alkyl chain length increases and how the introduction of charge induces further changes. [ABSTRACT FROM AUTHOR]

We report an H‐bond donor controlled diastereoselective switchable intramolecular aza‐Henry reaction of ketimines derived from α‐ketoesters and 2‐(2‐nitroethyl)anilines, allowing facile access to chiral tetrahydroquinolines bearing an aza‐quaternary carbon stereocenter, which are privileged scaffold for medicinal researches. While newly developed cinchona alkaloid derived phosphoramide‐bearing quaternary ammonium salt C2 selectively give cis‐adducts in up to 20 : 1 dr and 99 % ee, the corresponding urea‐bearing analogue C8 preferentially give trans‐adducts in up to 20 : 1 dr and 99 % ee. [ABSTRACT FROM AUTHOR]

The current experimental investigation demonstrates the capability of neutron imaging to quantify cavitation, in terms of vapour content, within an orifice of an abruptly constricting geometry. The morphology of different cavitation regimes setting in was properly visualised owing to the high spatial resolution of 16 μm achieved, given the extensive field of view of 12.9 × 12.9 mm2 offered by the imaging set-up. At a second step, the method was proven capable of highlighting subtle differences between fluids of different rheological properties. More specifically, a reference liquid was comparatively assessed against a counterpart additised with a Quaternary Ammonium Salt (QAS) agent, thus obtaining a viscoelastic behaviour. In accordance with previous studies, it was verified, yet in a quantifiable manner, that the presence of viscoelastic additives affects the overall cavitation topology by promoting the formation of more localised vortical cavities rather than cloud-like structures occupying a larger portion of the orifice core. To the authors' best knowledge, the present work is the first to demonstrate that neutron imaging is suitable for quantifying in-nozzle cavitating flow at the micrometre level, consequently elucidating the distinct forms of vaporous structures that arise. The potential of incorporating neutron irradiation for the quantification of two-phase flows in metallic microfluidics devices has been established. [ABSTRACT FROM AUTHOR]

The development of novel synthetic methods for quaternary ammonium salts is highly demanded since the current synthesis heavily relies on the conventional Menshutkin reaction. Herein, we report photoredox-catalyzed alkylation of α-brominated alkenylammonium salts. Mechanistically, the generation of a highly reactive α-ammoniovinyl radical is the key to our method. This reaction enables the synthesis of various unprecedented α-alkylated alkenylammonium salts. [ABSTRACT FROM AUTHOR]

In this paper, small-molecule quaternary ammonium salts were synthesized by N-alkylation to inhibit hydration swelling and hydration dispersion. The prepared small-molecule quaternary ammonium salt was characterized by Fourier transform infrared (FTIR) spectroscopy, Thermogravimetric analysis (TGA), particle size analysis and Scanning electron microscopy (SEM), and its performance as an inhibitor in clay was evaluated by an anti-swelling test and a linear swelling test. The results show that small-molecule quaternary ammonium salt (TEE-2) synthesized by triethanolamine and epichlorohydrin in ethanol with a molar ratio of 1:1.5 can successfully inhibit the hydration swelling and dispersion of clay. The anti-swelling rate of TEE-2 was 84.94%, the linear swelling rate was 36.42%, and the linear swelling rate of 0.5% TEE-2 was only 29.34%. The hydration swelling of clay in 0.5% TEE-2 solution was significantly inhibited. The hydration inhibition mechanism of the small-molecule quaternary ammonium salt inhibitor 0.5% TEE-2 was analyzed by FTIR, SEM and TGA. It was considered that 0.5% TEE-2 has strong hydration inhibition, which was realized by infiltration and adsorption on the clay surface. Small-molecule quaternary ammonium salts were beneficial for maintaining wellbore stability and reducing the risk of wellbore instability. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) has been emerged as a promising modality for cancer treatment. However, the development of drug delivery system enabling continuous release of photosensitizers (PSs) for long-term PDT treatment still remains challenges. Herein, a H2O2-responsive injectable hydrogel, covalently crosslinked by N1-(4-boronobenzyl)-N3-(4-boronophenyl)-N1,N1,N3,N3-tetramethylpropane-1,3-diaminium (TSPBA) with PVA containing polythiophene quaternary ammonium salt (PT2) polymer dots (PDots) as a photosensitizer was fabricated. Under the stimulation of H2O2, the obtained injectable hydrogel gradually degrades and releases PDots. In vitro experiments suggested that the released PDots could realize efficient tumor cells inhibition through its robust singlet oxygen generation capability upon 577 nm laser irradiation. In vivo studies demonstrated a sustained retention of PDots for at least 7 days following single-dose administration, facilitating efficient tumor inhibition with light treatments for 3 times without apparent biotoxicity. This work presents an innovative polymer dots-based composite local drug delivery system for long-term PDT in cancer treatment. [ABSTRACT FROM AUTHOR]

Purpose: At present, research on the preparation of corrosion inhibitors using modified pyrimidine derivatives is still blank. The purpose of this study is to synthesize a new cationic mercaptopyrimidine derivative quaternary ammonium salt, known as DTEBTAC, that can be used as a corrosion inhibitor to slow down the metal corrosion problems encountered in oil and gas extraction processes. Design/methodology/approach: A new corrosion inhibitor was synthesized by the reaction of anti-Markovnikov addition and nucleophilic substitution. The weight loss method was used to study the corrosion inhibition characteristics of synthetic corrosion inhibitors. Electrochemical and surface topography analyses were used to determine the type of inhibitor and the adsorption state formed on the surface of N80 steel. Molecular dynamics simulations and quantum chemistry calculations were used to investigate the synthetic corrosion inhibitor's molecular structure and corrosion inhibition mechanisms. Findings: The results of the weight loss method show that when the dosage of DTEBTAC is 1%, the corrosion rate of N80 steel in hydrochloric acid solution at 90? is 3.3325 g m-2 h-1. Electrochemical and surface morphology analysis show that DTEBTAC can form a protective layer on the surface of N80 steel, and is a hybrid corrosion inhibitor that can inhibit the main anode. Quantum chemical parameter calculation shows that DTEBTAC has a better corrosion inhibition effect than DTP. The molecular dynamics simulation results show that DTEBTAC has stronger binding energy than DTP, and forms a network packing structure through hydrogen bonding, and the adsorption stability is enhanced. Originality/value: A novel cationic mercaptopyrimidine derivative quaternium-ammonium salt corrosion inhibitor was designed and provided. Compared with the prior art, the preparation method of the synthesized mercaptopyrimidine derivative quaternary ammonium salt corrosion inhibitor is simple, and the presence of nitrogen-positive ions, sulfur atoms and nitrogen-rich atoms has an obvious corrosion inhibition effect, which can be used to inhibit metal corrosion during oil and gas field exploitation. It not only expands the application field of new materials but also provides a new idea for the research and development of new corrosion inhibitors. [ABSTRACT FROM AUTHOR]

The paper presents the results of anticorrosion gravimetric studies of the quaternary nitrogen-containing derivatives of 2-allyl-4-isodecylphenol, namely, the quaternary ammonium salts 2-allyl-4-isodecyl-6-diethylaminomethylphenol (I) and 2-allyl-4-isodecyl-6-piperidinomethylphenol (II) on steel St.3 plates in a system consisting of a 3% aqueous NaCl solution and hydrocarbons (kerosene) at a ratio of 9 : 1 (vol/vol). The influence of the temperature and concentration of the compounds on the corrosion rate, metal surface coverage, and protective effect was studied (test time 5 h). Compounds I and II were found to have high inhibitory properties. The thermodynamic parameters of adsorption (ΔG, ΔH, ΔS) were determined, based on which the chemisorption blocking mechanism of steel St.3 surface protection was proposed. The chemisorption process is described by the Langmuir isotherm. [ABSTRACT FROM AUTHOR]

Enzymatic strengthening and cellulase recovery are effective ways for improving the economy of lignocellulosic hydrolysis. A series of temperature‐responsive quaternary ammonium salt type enzymatic hydrolysis promoters (PSDM) were obtained by aqueous‐solution free radical polymerization. PSDM dissolved under lignocellulosic enzymatic hydrolysis conditions (50°C). After hydrolysis, it co‐precipitated with cellulase when cooling. PSDM had significantly improved hydrolysis and recycling enzyme properties. The efficiency of high‐solid substrate enzymatic hydrolysis of corncob residues improved to 1.2 times, and 50% of the cellulase amount was saved when adding 1.5 g/L of PSDM1 to the system. Hydrophobic binding may be the main driving force for co‐precipitation between PSDM and cellulase. In this work, regulation of glucose yield and cellulase consumption were realized by adjusting the ratio of positive and negative charges in PSDM. This work provides a new idea for reducing the cost of technology for this lignocellulosic sugar platform. [ABSTRACT FROM AUTHOR]

Abstract Quaternary ammonium compounds (QACs) are a biologically active group of chemicals with a wide range of different applications. Due to their strong antibacterial properties and broad spectrum of activity, they are commonly used as ingredients in antiseptics and disinfectants. In recent years, the spread of bacterial resistance to QACs, exacerbated by the spread of infectious diseases, has seriously threatened public health and endangered human lives. Recent trends in this field have suggested the development of a new generation of QACs, in parallel with the study of bacterial resistance mechanisms. In this work, we present a new series of quaternary 3-substituted quinuclidine compounds that exhibit potent activity across clinically relevant bacterial strains. Most of the derivatives had minimal inhibitory concentrations (MICs) in the low single-digit micromolar range. Notably, QApCl and QApBr were selected for further investigation due to their strong antibacterial activity and low toxicity to human cells along with their minimal potential to induce bacterial resistance. These compounds were also able to inhibit the formation of bacterial biofilms more effectively than commercial standard, eradicating the bacterial population within just 15 min of treatment. The candidates employ a membranolytic mode of action, which, in combination with the generation of reactive oxygen species (ROS), destabilizes the bacterial membrane. This treatment results in a loss of cell volume and alterations in surface morphology, ultimately leading to bacterial cell death. The prominent antibacterial potential of quaternary 3-aminoquinuclidines, as exemplified by QApCl and QApBr, paves the way for new trends in the development of novel generation of QACs.

Colorectal cancer (CRC) is a multifactorial disease driven by genetic and epigenetic alterations that modulate specific metabolic pathways. Despite the availability of effective treatments like 5‐fluorouracil (5‐FU), pharmacological therapy for CRC still faces significant challenges, including drug resistance, toxicity, and limited specificity. Therefore, discovering new compounds remains critical to overcoming these barriers and expanding treatment options. This study evaluated the cytotoxicity of fluorinated quaternary ammonium salts (FQAS) library in CRC‐derived cell lines with premetastatic and metastatic phenotypes. The genetic and epigenetic background of the CRC cell lines and the selectivity of cytotoxicity compared to nontumor cells and between different CRC stages were also assessed. Additionally, the in silico pharmacological properties of these FQASs were analyzed. Results showed that FQASs 9–14 exhibited significant cytotoxic activity against both premetastatic and metastatic CRC cell lines, with FQASs 9, 13, and 14 displaying selective toxicity toward CRC cells over normal murine colorectal cells. However, in silico studies indicated poor oral bioavailability for these compounds, suggesting that an injection‐based delivery route may be more effective for targeting CRC cells. In conclusion, CF3‐containing FQASs are promising therapeutic candidates for CRC treatment. [ABSTRACT FROM AUTHOR]

Reaction of a quaternary ammonium salt with GaCl3 in concentrated HCl aqueous solution led to an organic–inorganic hybrid perovskite material [Me3NCMe3][GaCl4] (1), which shows a two-step off–on–off second harmonic generation (SHG) response with a rapid and large temperature interval. [ABSTRACT FROM AUTHOR]

The present study explores the cleaning efficacy of a set of nonionic surfactants (linear ethoxylated alcohol, secondary ethoxylated alcohols with 5, 7, and 9 ethoxy groups, glycoside surfactants, polyglycerol surfactants, and an ethoxylated sorbitan monolaurate) combined with cationic biocides—alkyl quaternary ammonium salts. A simple hard surface cleaning methodology was applied, which was shown to discriminate well between poor and good cleaning formulations. In addition to cleaning efficacy, surface aesthetics such as gloss and haze were evaluated together to assess surface streaking caused by a residual surfactant layer. The haziness determination turned out to be the key feature revealing the complex cleaning performance of multi‐component products. [ABSTRACT FROM AUTHOR]

The double skeleton interpenetrating network fixed the quaternary ammonium salt, and various internal conduction modes cooperated to promote the transport of hydroxide ions. [Display omitted] The alkaline solid-state electrolytes have received widespread attention for their good safety and electrochemical stability. However, they still suffer from low conductivity and poor mechanical properties. Herein, we report the synthesis of double-network featured hydroxide-conductive membranes fabricated by polyvinyl alcohol (PVA) and chitosan (CS) as the double-skeletons. Then, we implanted quaternary ammonium salt guar hydroxypropyltrimonium chloride (GG) as the OH− conductor for high-performance electrochemical devices. By virtue of the unique stripe-like structure shared from the double skeleton with a high degree of compatibility and stronger hydrogen bond interactions, the polyvinyl alcohol/chitosan-guar hydroxypropyltrimonium chloride (PCG) solid-state electrolytes achieved optimal thermal stability (> 300 °C), mechanical property (∼ 34.15 MPa), dimensional stability (at any bending angle), and high ionic conductivity (13 mS cm−1) and ion mobility number (t ion ∼ 0.90) compared with chitosan-guar hydroxypropyltrimonium chloride (CG) and polyvinyl alcohol-guar hydroxypropyltrimonium chloride (PG) electrolyte membrane. As a proof-of-concept application, the "sandwich"-type zinc-air battery (ZAB) assembled using PCG membrane as the electrolyte realized a high open-circuit voltage (1.39 V) and an excellent power density (128 mW cm−2). Notably, in addition to its long-term cycle life (30 h, 2 mA cm−2) and stable discharge plateau (12 h, 5 mA cm−2), it could even enable a flexible ZAB (F-ZAB) to readily power light-emitting diodes (LED) at any bending angle. These merits afford the PCG membrane a promising electrolyte for improving the performance of solid-state batteries. [ABSTRACT FROM AUTHOR]

Fly ash washing wastewater was carbonated with carbon dioxide (CO2) to remove calcium (Ca) by forming a calcium carbonate (CaCO3) precipitate. An investigation of the factors affecting carbonation showed that Ca removal was highly dependent on the initial pH of the wastewater. The Ca removal was 10%, 61%, 91% and more than 99% at initial wastewater pH levels of 11.8, 12.0, 12.5 and 13.0, respectively. The optimal conditions for carbonation were initial pH of 13.0, carbonation time of 30 min and CO2 flow rate of 30 mL/min. The Ca concentration in the wastewater decreased to <40 mg/L, while 73 g of CaCO3 precipitate was produced per liter of wastewater. However, heavy metals, specifically Pb and Zn, co-precipitated during carbonation, which resulted in a CaCO3 product that contained as much as 0.61 wt% of Pb and 0.02 wt% of Zn. Activated carbon modified by a quaternary ammonium salt was used to selectively adsorb the Pb and Zn first. The Pb- and Zn-free water was then carbonated. By combining adsorption with carbonation, the Ca concentration in the treated wastewater was decreased to about 28 mg/L, while the Na, Cl and K were retained. The wastewater thus treated was ready for NaCl and KCl recovery. In addition, the precipitate had a Ca content of more than 38 wt% and almost no heavy metals. The average particle size of the precipitate was 47 μm, with a uniform cubic shape. The quality of the precipitate met the requirements for the industrial reuse of CaCO3. In summary, adsorption and carbonation combined were able to remove pollutants from wastewater while recovering useful resources. [ABSTRACT FROM AUTHOR]

AbstractIn this paper, the inhibition efficiency and mechanism of a newly synthesized imidazoline-pyridine quaternary amine salt (IPS) as a corrosion inhibitor for carbon steel in 1.00 mol/L HCl at different temperatures were investigated experimentally and theoretically. The inhibitor is confirmed by nuclear magnetic resonance spectroscopy (NMR) and fourier transform infrared spectroscopy (FT-IR). Electrochemical and weight loss indicate that the IPS displays a stable protection performance at different temperatures. Moreover, scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS) indicates that the IPS can be stably adsorbed on Q235 steel surface. Molecular dynamics (MD) show that mainly imidazole and pyridine rings of IPS are adsorbed on the surface of Fe. Moreover, radial distribution function (RDF) and the mean-square displacement (MSD) were used to study inhibitor/metal interactions and migration rate of corrosive species, respectively. The results can provide useful guidance for further study on the corrosion inhibition of imidazole-pyridine quaternary amine salts. [ABSTRACT FROM AUTHOR]

Highly complex fused systems are widely present in drug development. The direct electrosynthesis of fused systems through radical domino reactions features higher atom and step economy, using abundantly available starting materials and avoiding exogenous oxidants and reductants, and thus it has been in high demand and recognized as a green, powerful, and versatile synthetic tool but remains challenging because of the instability of the radical species under the electrolysis conditions and the inclusion of a quaternary ammonium salt. Herein, we developed a de novo electrosynthesis of 6-6-5 fused systems with two new rings constructed using a user-friendly undivided cell through decarboxylation and three-step radical addition under exogenous oxidant and quaternary ammonium salt free conditions. Excellent functional group, water and air compatibility was observed with good yields obtained. [ABSTRACT FROM AUTHOR]

The grafting of trialkoxysilanes is the most common method for the surface functionalization of silica gel, and it is usually carried out in the presence of toluene or other solvents such as acetonitrile or acetone. Here, we replaced these solvents with alcohols to afford silica materials containing alkoxy groups linked to the silicon atom. The grafting of N,N-dimethyl-3-amino- or 3-amino-propyltrimethoxysilane was carried out in the presence of several alcohols containing an unsubstituted alkyl chain (C7 and C14), a PEG functionalized chain, or an amino-substituted chain (N,N-dimethylamino, pyridyl). Materials were characterized via solid-state 13C- and 29Si CPMAS NMR and thermogravimetric analysis to prove that alcohols are not "innocent" solvents but take part in the reaction and lead to [RSi(OR1)-(OSi)2] systems where the OR1 group proceeds from the alcohol used in the synthesis. As a proof of concept, we briefly studied the catalytic activity of some of these materials with the aim of showing how different modifications can influence the course of a selected reaction. Finally, a quaternary ammonium salt (QAS)-based silica was prepared containing both an alkyl-QAS and an alkoxy-QAS linked to silicon atoms. This could represent an interesting approach for the development of new antifouling-based materials and, overall, the described strategy could be useful for the preparation of new organosilica materials. [ABSTRACT FROM AUTHOR]

The quaternized chitosan has promising applications in biomedicine as pharmaceuticals and targeted delivery, in gene therapy, tissue engineering, and cosmetology due to the improved solubility and enhancing many biological functions in comparison to the non-quaternized chitosan. The increased demand for such applications is achieved through the beneficial combination of the inherent properties of chitosan with those of quaternized ammonium salts. Various synthesis methods have been developed for the synthesis of quaternary ammonium salts of chitosan. The each of these methods has its own advantages and disadvantages that affect on the product properties. The aim of this work was to choose the optimal ways of to quaternized polymers, and the immobilization of drugs L-thyroxine and doxycycline on its surface. IR spectroscopic analysis showed that the interaction of levothyroxine with chitosan occurs mainly due to hydrogen bonds and orientation forces of intermolecular interaction. IR-spectroscopic analysis of doxycycline also showed that the interaction of drug with chitosan takes place mainly due to hydrogen bonds and orientation forces. [ABSTRACT FROM AUTHOR]

In this study, poly(lactic acid), poly(ethylene glycol), and benzalkonium chloride with different concentrations (3, 5, 7, and 9%wt.) (PLA/PEG/BCL) composite electrospun mats were produced. PLA is a non‐toxic polymer with high biocompatibility and biodegradability. However, it may be fragile due to its structure. Therefore, in this study, PEG was used as a plasticizer to improve the structural properties of PLA and it was aimed at providing antibacterial properties by adding BCL salt. Its use as an antibacterial composite nanomaterial effective against Gram‐positive Staphylococcus aureus (S. aureus) and Gram‐negative Escherichia coli (E. coli) bacterial cultures and as a dermal wound dressing material has been examined in two different areas. The addition of BCL salt reduced the bead formation in PLA/PEG nanofibers and increased the homogeneity of fiber dispersion. 9% BCL‐doped composite nanofiber was obtained as the smoothest and most homogeneous surface. This mat was reported to have the highest ductility. The low Tm of pure BCL salt enabled the Tg temperature of PLA/PEG/BCL composite nanofibers to be observed. It was observed that as the BCL salt ratio increased, the T5 and T10 temperatures of the nanofibers decreased and then increased. BCL‐doped mats exhibited liquid absorption behavior in the range of 497%–708%. PLA/PEG/BCL composite nanofibers showed high toxicity to the L929 fibroblast cell line. So, it has been reported that it cannot be used as a dermal wound dressing. PLA/PEG/BCL composite nanomaterials were reported to have 99.99% antibacterial activity against E. coli and S. aureus. It was suggested that it could be used in antibacterial coating applications by taking into account modern nanocoating technology. Highlights: Poly(lactic acid), poly(ethylene glycol), and benzalkonium chloride (PLA/PEG/BCL) composite electrospun mats were produced.The addition of BCL salt reduced the bead formation in PLA/PEG nanofibers and increased the homogeneity of fiber dispersion.9% BCL‐doped composite nanofiber was obtained as the smoothest and most homogeneous surface.PLA/PEG/BCL composite nanofibers showed high toxicity to the L929 fibroblast cell line.PLA/PEG/BCL composite nanomaterials were reported to have 99.99% antibacterial activity against E. coli and S. aureus. [ABSTRACT FROM AUTHOR]

Four ester cationic Gemini surfactants (EDQ‐n, n represents the carbon number in the raw fatty acid of 12, 14, 16 and 18) were synthesized from fatty acid, N, N‐dimethylethanolamine and 1, 4‐dibromobutane by two‐step reaction of esterification and quaternization. Their surface activities at air/water interface were investigated. The application performance such as water solubility, antistatic property, fabric softness, fabric whiteness, biodegradability, and antibacterial activities were tested and compared with traditional quaternary ammonium salt. The results showed that the γcmc increases with increasing the hydrophobic chain length and EDQ‐12 presented the highest surface activity. The diffusion coefficients calculated from the Ward‐Tordai equation indicates the adsorption process is a mixed‐diffusion kinetic adsorption mechanism. The water solubility of EDQ‐n is higher than dioctadecyl dimethyl ammonium chloride (D1821) and ester quaternary ammonium salt (Esterquats). The fabric softness and whiteness properties of EDQ‐16 and EDQ‐18 are similar to D1821 and Esterquats, which can significantly reduce the cotton fabric softness and have no significant difference in whiteness retention. EDQ‐n demonstrated more readily biodegradation(>90 %) than D1821(0 %) after seven days. In addition, EDQ‐12 and EDQ‐14 show excellent antibacterial activities against Staphylococcus aureus and Escherichia coli in comparison with conventional bacteriostatic agent didecyl dimethyl ammonium chloride (DDAC). [ABSTRACT FROM AUTHOR]

Liposomes have been extensively applied in gene and drug delivery. It is indicated in many studies that cationic lipids possess a certain degree of cytotoxicity, primarily induced by the lipid head group. In this study, we investigated the cytotoxic mechanisms of peptide headgroup lipid (CDO14) and quaternary ammonium salt headgroup lipid (CDA14) on the NCI-H460 and MRC-5 cell lines. Both lipids were synthesized in our laboratory and with high transfection efficiency. The differences in changes of relevant proteins during the process of inducing cell apoptosis were compared at the cellular level between the two lipids. The results showed that both types of liposomes could lead to an increase in intracellular reactive oxygen species, a decrease in ATP content, a decrease in mitochondrial membrane potential, an increase in cytochrome c content, an increase in the BAX/BCL-2 ratio, and an increase in cleaved caspase-3 content. Among these changes, the variations in CDA14 were more significant than those in CDO14. Additionally, the cellular uptake of CDA14 was significantly higher than that of CDO14. These results suggested that the cytotoxicity of quaternary ammonium salt-based lipids was higher than that of peptide-based lipids. The cytotoxicity of cationic lipids is related to their head group structure, and their cytotoxic effect is mainly achieved by activating caspase-dependent endogenous apoptosis. [ABSTRACT FROM AUTHOR]

Ultrafiltration (UF) membranes with excellent dye removal and antibacterial activity are highly desired in dye wastewater treatment, and more importantly environmental protection puts high demands on polymeric membrane materials. In this work, three methacrylate copolymers containing quaternary ammonium salt were synthesized to cast UF membranes. The physicochemical property, structural evolution, dye separation, and antibacterial activity of as‐prepared membranes were systematically investigated. With increased content of the hydrophilic monomer allyl polypropylene glycol (APPG) in the feed, the wettability and positive charge of the resultant membranes were enhanced. Remarkably, the supporting layer of membranes changed from finger‐like pore structure to sponge‐like pore structure by increasing APPG content, and the sponge‐like membranes showed higher retention rates for dyes (99.78% for victoria blue B, 90.49% for methylene blue, and 97.43% for methyl blue) compared with the finger‐like membranes. Besides, the sponge‐like membranes exhibited high rejection for vctoria blue B (>99%) in dye/salt mixture and simultaneously low rejection for salts (<10%), indicating effective selective separation to dye/salt mixture, and also achieved easy regeneration. It was also found that increased hydrophilicity and positive charge endowed membranes with better antibacterial activity. This work will provide an alternative for dye/salt selective separation in dye effluent treatment. [ABSTRACT FROM AUTHOR]

Using natural deep eutectic solvents (NADESs) as a green reagent is a step toward producing environmentally friendly and sustainable technology. This study screened three natural DESs developed using quaternary ammonium salt and organic acid to analyse their capability to extract nickel ions from contaminated mangrove soil, which are ChCl: Acetic Acid (ChCl-AceA), ChCl: Levulinic Acid (ChCl-LevA), and ChCl: Ethylene Glycol(ChCl-Eg) at molar ratio 1:2. The impact of various operating parameters such as washing agent concentration, pH solution, and contact time on the NADES performance in the dissolution of Ni ions batch experiments were performed. The optimal soil washing conditions for metal removal were 30% and 15% concentration, a 1:5 soil-liquid ratio, and pH 2 of ChCl-LevA and ChCl-AceA, respectively. A single removal washing may remove 70.8% and 70.0% Ni ions from the contaminated soil. The dissolution kinetic of Ni ions extraction onto NADES was explained using the linear kinetic pseudo and intraparticle mass transfer diffusion models. The kinetic validation demonstrates a good fit between the experimental and pseudo-second-order Lagergren data. The model's maximum Ni dissolution capacity, Qe are 51.56 mg g−1 and 52.00 mg g−1 of ChCl-LevA and ChCl-AceA, respectively. The synthesised natural-based DES has the potential to be a cost-effective, efficient, green alternative extractant to conventional solvent extraction of heavy metals. [ABSTRACT FROM AUTHOR]

Antibacterial materials with high hydrophobicity have drawbacks such as protein adsorption, bacterial contamination, and biofilm formation, which are responsible for some serious adverse health events. Therefore, antibacterial materials with high hydrophilicity are highly desired. In this paper, UV‐curable antibacterial materials are prepared from silicone−containing Choline chloride (ChCl) functionalized hyperbranched quaternary ammonium salts (QAS) and tri−hydroxylethyl acrylate phosphate (TAEP). The materials show high hydrophilic performance because their water contact angle is as low as 19.3°. The materials also exhibit quite high antibacterial efficiency against S. aureus over 95.6%, fairly high transmittance over 90%, and good mechanical performance with tensile strength as high as 6.5 MPa. It reveals that it is a feasible strategy to develop antibacterial materials with low hydrophobicity from silicone‐modified ChCl‐functionalized hyperbranched QAS. [ABSTRACT FROM AUTHOR]

The application properties such as foam property, electrolyte tolerance, antibacterial activity and antistatic performance of the mixed systems of a novel Gemini quaternary ammonium salt with quadra‐cationic sites (TC‐GS) and sodium fatty alcohol polyoxyethylene ether carboxylate (AE9CNa) at various molar fraction of TC‐GS (αTC‐GS), were investigated systematically. Results show that TC‐GS/AE9CNa mixed systems with different ratios form a homogeneous and transparent solution, which exhibits excellent foam stability and antibacterial activity. The foam volume of the mixed system remains nearly constant from 400 s to 1000 s, and even when TC‐GS is 10 mg/L in the mixed systems, the antibacterial rates against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) for 2 min. are all exceeded 99 %. The mixed systems of TC‐GS/AE9CNa at various αTC‐GS also demonstrate the superior electrolyte tolerance, their maximum tolerance of NaCl, CaCl2 and MgCl2 is severally beyond 270 g/L, 180 g/L and 180 g/L. In addition, both TC‐GS solution and the mixed systems have good antistatic properties, which can reduce the surface resistance of polyester fabric to ≤1010 Ω. [ABSTRACT FROM AUTHOR]

The article presents the results of the study of the oil collecting and oil dispersing properties of the quaternary ammonium salts formed by undecanoic and tetradecanoic acids, which are monobasic carboxylic acids, with triethanolamine (TEA) in distilled, drinking, and sea waters contaminated with Balakhani Oil. The surface activity property of the products of different concentrations of these complexes was calculated using a tensiometer, and the elemental composition was calculated using the calculation method. A comparative study of the element composition of the salts of both acids formed with TEA shows that the mass fraction of carbon in the complex formed by tetradecanoic acid with TEA is higher than in the other complex. Comparison of the surface activity property of the complexes formed by undecane and tetradecanoic acid with TEA shows that the complex compound formed by tetradecanoic acid with TEA shows more surface activity property. Therefore, as the mass fraction of carbon element increases in the complexes formed by undecane and tetradecanoic acid with TEA, the complex compound shows more surface activity properties. [ABSTRACT FROM AUTHOR]

This study focused on developing an advanced bitterness sensor designed to minimize interference from common anions such as nitrate (NO3−) and iodide (I−) by incorporating partially dissociated amine compounds into the sensor membrane. The conventional bitter sensor (C00) uses fully dissociated quaternary ammonium salt tetradecyl ammonium bromide (TDAB), which typically exhibits high responses to these anions, leading to inaccurate bitterness assessments. To address this issue, we explored the use of three partially dissociated amines—oleylamine (OAm), dioctadecylamine (DODA), and tridodecylamine (TDA)—as lipids in the membrane components. We fabricated sensor membranes and tested their ion selectivity, interference resistance to anion, and sensitivity to iso-alpha acids (IAAs), representative bitter compounds in beer. The results showed that the membranes with partially dissociated amines significantly reduced anion interference. Notably, the sensitivity of the TDA membrane to IAAs was 80.4 mV/dec in concentration, exceeding the 68.5 mV/dec of the TDAB membrane. This enhanced sensitivity, coupled with reduced anion interference, reveals a novel property of partially dissociated lipids in taste sensors, distinguishing them from fully dissociated lipids. These findings pave the way for the development of sensors that can accurately assess a bitter taste and have potential applications in the food and beverage industry. [ABSTRACT FROM AUTHOR]

pH-responsive hydrogel antibacterial microspheres were prepared by complex coacervation method and used as drug carriers to load the antibiotic substitute potassium diformate (KDF). The results showed that the three-dimensional network structure of the composite hydrogel was formed among the polysaccharide components, and Zeolite A loaded with KDF was uniformly dispersed in it. The results of drug release behavior and kinetics in vitro showed that the drug release rate was higher and the release mechanism followed the Ritger-Peppas model, which indicated that the antibacterial microspheres had a good pH response. In vitro, the carrier showed broad-spectrum antibacterial activity, good biocompatibility, and degradability. Sodium carboxymethylcellulose and pectin synergistic by hydrogen bonding, potassium dicarboxylate-loaded Zeolite A is filled in a three-dimensional hydrogel network, and chitosan quaternary ammonium salts coat the outer layer. [ABSTRACT FROM AUTHOR]

Quaternary ammonium salts (QASs) have been used as antimicrobial agents, surfactants, and ionic liquids in electrical double-layer capacitors, rechargeable lithium-ion batteries, and dye-sensitized solar cells. It is well known that solvents and reactants strongly affect the Menshutkin reaction. However, QASs are potentially harmful to humans and the environment. To address these issues, we report the effects of solvent polarity on the thermochemistry of two selected Menshutkin reactions, (1) trimethylamine and 1-iodopropane yielded propyltrimethylammonium, and (2) methylacetamide and 1-iodopropane yielded acetylpropylmethylammonium. We systematically constructed possible QAS unique conformers within the first-principles framework in solvents that have three various polarities: toluene, acetonitrile, and water. The polar solvent shifted both reactions toward exergonic and decreased the Gibbs free activation energy. In addition, the polar solvent changed the favorable reaction for the acetylpropylmethylammonium formation only due to an intramolecular hydrogen bond. Therefore, we suggest that selecting high solvent polarity should be considered to address the potential health and environmental effect. [ABSTRACT FROM AUTHOR]

The current study investigates the production of organoclay suitable for use in the base section of a passenger tire with a cap/base tread construction. The process involved the purification and modification of two types of sodium bentonite clay with different mineral characteristics and ion exchange capacities using a single-step process. The modification process of purified bentonite suspensions was performed using a two-tailed long-chain alkyl quaternary ammonium salt surfactant, namely di (hydrogenated tallow alkyl) dimethyl ammonium chloride (AD2HT), and two one-tailed long-chain alkyl quaternary ammonium salt surfactants, namely cetyl-trimethylammonium chloride (CTAC) and octadecylamine chloride (ODA), in relatively low amounts of surfactant (0.95 CEC), along with polyethylene glycol (4% clay) as an auxiliary modifier. X-ray diffraction (XRD) showed that the interlayer spacing of organoclays significantly increases. In addition, the XRD pattern depends on the kind of surfactant and is independent of the type of bentonite clay. The resulting organoclays were added to the tread base section of a passenger tire using the melt masterbatch technique along with a silane coupling agent. An increase in curing maximum torque (8–15%), curing delta torque (6–14%), hardness (2–10%), static modulus 300 (2–18%), and dynamic storage modulus (11–30%) of the rubber composites was observed without significant change of resilience and loss factor of the composite at 2 Phr of organoclay loadings. The organoclays based on the AD2HT modifier exhibited better mechanical properties than those based on the ODA and CTAC surfactants. The dynamic storage modulus of composites increased by about 30% with only 2 Phr of AD2HT-modified bentonites. Furthermore, the performance of the organoclay was found to be independent of the primary particle size, iron content, and ion exchange capacity of the bentonite clay within the studied range. [ABSTRACT FROM AUTHOR]

In order to improve the electrical conductivity of nylon 6 (PA6) and avoid misfires and explosions caused by static charge accumulation, a quaternary ammonium salt polyionic liquid (PIL) antistatic agent was synthesized in this paper. The surface resistance of PA6 was reduced to 108Ω with the addition of 2 wt% antistatic agent, and the mechanical properties and aging resistance of the substrate were improved. Meanwhile, the morphology and crystallinity of PIL/PA6 composites were further characterized by scanning electron microscope (SEM), energy dispersion spectrometer (EDS) and X-ray diffraction (XRD). It is worth noting that the quaternary ammonium salt polyionic liquid antistatic agent synthesized in this paper has the advantages of excellent antistatic effect, durability, low cost, and simple reaction condition, so it has a broad application prospect in the antistatic aspect of PA6. [ABSTRACT FROM AUTHOR]

The increasing emergence of multidrug-resistant (MDR) pathogens due to antibiotic misuse translates into obstinate infections with high morbidity and high-cost hospitalizations. To oppose these MDR superbugs, new antimicrobial options are necessary. Although both quaternary ammonium salts (QASs) and phosphonium salts (QPSs) possess antimicrobial effects, QPSs have been studied to a lesser extent. Recently, we successfully reported the bacteriostatic and cytotoxic effects of a triphenyl phosphonium salt against MDR isolates of the Enterococcus and Staphylococcus genera. Here, aiming at finding new antibacterial devices possibly active toward a broader spectrum of clinically relevant bacteria responsible for severe human infections, we synthesized a water-soluble, sterically hindered quaternary phosphonium salt (BPPB). It encompasses two triphenyl phosphonium groups linked by a C12 alkyl chain, thus embodying the characteristics of molecules known as bola-amphiphiles. BPPB was characterized by ATR-FTIR, NMR, and UV spectroscopy, FIA-MS (ESI), elemental analysis, and potentiometric titrations. Optical and DLS analyses evidenced BPPB tendency to self-forming spherical vesicles of 45 nm (DLS) in dilute solution, tending to form larger aggregates in concentrate solution (DLS and optical microscope), having a positive zeta potential (+18 mV). The antibacterial effects of BPPB were, for the first time, assessed against fifty clinical isolates of both Gram-positive and Gram-negative species. Excellent antibacterial effects were observed for all strains tested, involving all the most concerning species included in ESKAPE bacteria. The lowest MICs were 0.250 µg/mL, while the highest ones (32 µg/mL) were observed for MDR Gram-negative metallo-β-lactamase-producing bacteria and/or species resistant also to colistin, carbapenems, cefiderocol, and therefore intractable with currently available antibiotics. Moreover, when administered to HepG2 human hepatic and Cos-7 monkey kidney cell lines, BPPB showed selectivity indices > 10 for all Gram-positive isolates and for clinically relevant Gram-negative superbugs such as those of E. coli species, thus being very promising for clinical development. [ABSTRACT FROM AUTHOR]