Bis-quaternary Ammonium Research Articles

Fabrication and Application of Tannin Double Quaternary Ammonium Salt/Polyvinyl Alcohol as Efficient Sterilization and Preservation Material for Food Packaging.

Food packaging films play a vital role in preserving and protecting food. The focus has gradually shifted to safety and sustainability in the preparation of functional food packaging materials. In this study, a bisquaternary ammonium salt of tannic acid (BQTA) was synthesized, and the bioplastics based on BQTA and polyvinyl alcohol (PVA) were created for packaging applications. The impact of BQTA on antibacterial effect, antioxidant capacity, opacity, ultraviolet (UV) protective activity, mechanical strength, thermal stability, and anti-fog of the resultant bioplastics was examined. In vitro antibacterial experiments confirmed that BQTA possesses excellent antimicrobial properties, and only a trace amount addition of BQTA in PVA composite film could inhibit about 100% of Escherichia coli and Staphylococcus aureus. Compared to BQTA/PVA bioplastics with pure PVA, the experiment findings demonstrate that BQTA/PVA bioplastics show strong antioxidant and UV protection action and the performance of fruit preservation. It also revealed a small improvement in thermal stability and tensile strength. The small water contact angle, even at low BQTA concentrations, gave BQTA/PVA bioplastics good anti-fog performance. Based on the findings, bioplastics of BQTA/PVA have the potential to be used to create packaging, and they can be applied as the second (inner) layer of the primary packaging to protect food freshness and nutrition due to their antioxidant activity and biocompatibility.

Insights into the Synthesis of Spiral Beta Zeolite with Enhanced Catalytic Performance in VOC Abatement.

The rational synthesis of zeolites with designed morphology is a highly challenging task. In this study, we propose 1,5-bis(methylpiperidine)pentylammonium hydroxide (BMPPAOH) as an organic structure-directing agent (OSDA) based on theoretical calculations. The morphology of zeolite samples is characterized by XRD, SEM, TEM, N2 sorption isotherms, and UV Raman spectroscopy. This simple bis-quaternary ammonium salt favored the formation of spiral morphology in Beta zeolite spheres (S-Beta). The crystallization of zeolite in the presence of BMMPAOH is a two-stage process, where nanoparticles agglomerate into spheres in the early stages followed by the emergence of S-Beta crystals with spiral morphology. The synthesized Pt-S-Beta catalysts show higher catalytic activity in VOC abatement compared with other Pt-Beta samples.

A Novel Bisquaternary Ammonium Compound as an Anion Sensor-ESI-MS and Fluorescence Study.

Electrospray ionization mass spectrometry (ESI-MS) analysis is frequently associated with noncovalent adduct formation, both in positive and negative modes. Anion binding and sensing by mass spectrometry, notably more challenging compared to cation binding, will have major research potential with the development of appropriate sensors. Here, we demonstrated identification of stable bisquaternary dication adducts with trifluoroacetate (TFA-), Cl- and HSO4- in positive-mode ESI-MS analysis. The observed adducts were stable in MS/MS mode, leading to the formation of characteristic fragment ions containing a covalently bound anion, which requires bond reorganization. This phenomenon was confirmed by computational methods. Furthermore, given that anion detection and anion sensor chemistry have gained significant prominence in chemistry, we conducted an analysis of the fluorescent properties of bisquaternary ammonium compound as a potential anion sensor.

Synthesis and antibacterial activity of new bis-quaternary ammonium compounds based on polyhydric alcohol

Synthesis and antibacterial activity of new bis-quaternary ammonium compounds based on polyhydric alcohol

Synthesis, antibacterial, and antibiofilm activities of pulmonarin B analogues

New analogues of pulmonarin B were synthesized from (3,5-dibromo-4-hydroxyphenyl)acetic acid derivatives, and their antibacterial and antibiofilm activities against E. coli, S. aureus, and P. aeruginosa were evaluated. The antibacterial activity of synthesized ammonium salts against the methicillin-resistant strain of S. aureus 222 depends on the length of the alkyl chain. Bis-quaternary ammonium salt 5 demonstrated better activity against S. aureus 222, E. coli 311, and P. aeruginosa 449 compared to mono-alkylated derivatives. Analogues of pulmonarin B 5 and 4d reduced S. aureus 222 biofilm formation by 74.5% and 89.4%, respectively. In addition, compound 4c turned out to be the most active against the biofilm formation of P. aeruginosa 449 (biomass decreased by 39.8%).

Study on the epoxidation of chain olefins using biquaternary ammonium phosphotungstic acid phase transfer catalysts under no-solvent condition.

In this study, we have developed a novel catalyst synthesized by phosphotungstic acid and a gemini quaternary ammonium cation salt. This quaternary ammonium salt not only reduces the interfacial tension between olefins and hydrogen peroxide but also forms a notably stable structure with phosphotungstic acid. Dodecene was successfully epoxidized to epoxy dodecane with a selectivity of 82.9 %. The impact of initial conditions was systematically investigated such as molar ratio, temperature, reaction time, and catalyst dosage on the catalytic performance. Characterization of the catalyst morphology was performed by SEM, TEM and SAXS. Raman spectra, FT-IR and XPS spectra were employed to perform the catalyst transformation during the epoxidation reaction. This catalytic mechanism study could provide the industrial application in the epoxidation of long-chain olefins.

The synthesis of bisquaternary ammonium compounds (microreview)

The synthesis of bisquaternary ammonium compounds (microreview)

A novel approach to mixed micelles formation: study the interactions between bis-quaternary ammonium salts and nonionic surfactant Triton X-100

Abstract This article focuses on the description of novel mixed system formulations of bis-quaternary ammonium salts (bis-QASs) and the nonionic surfactant Triton X-100 (TX-100). Measurements of surface tension (γ), foam stability, contact angle (CA) and cloud point (CP) were investigated at different ratios of the given compounds. The results indicated that changes in the structure of the bis-QASs amphiphilic cation, including the length of the alkyl spacer and the presence or absence of –OH groups, affected the adsorption and micellization. Furthermore, the elongation of the alkyl spacer in the bis-QASs structure affects the increase in the CP temperature. The research carried out shows the future potential of mixed combinations (bis-QASs and TX-100) to be used in industrial applications.

Cationic-anionic surfactant mixtures based on gemini surfactant as a candidate for enhanced oil recovery

The surface and interfacial properties of bisquaternary ammonium salts (16−4−16), sodium dodecyl benzene sulfonate (SDBS), and their mixture were investigated. Moreover, the effects of adsorption on the crude oil/water interfacial tension (IFT) of the SDBS/16–4–16 mixture were examined. Finally, the wettability alternation, oil film peeling-off performance, and core flooding were used to evaluate the enhanced oil recovery of the SDBS/16–4–16 mixture. Results show that the cationic Gemini surfactant 16–4–16 exhibits a strong synergistic effect with SDBS in surface/interfacial activity. At αSDBS = 0.66, the CMC value of the SDBS/16–4–16 mixtures reaches the lowest (0.016 mmol/L), and the interaction parameter (βm) exhibits a minimal value (−11.47), indicating a strong attraction between the cationic and anionic surfactants. When αSDBS is between 0.2 and 0.7, the diesel/water IFT is reduced below 10−2 mN/m, and the IFT shows little relationship with the mixing ratio. For crude oil, when αSDBS is equal to 0.4 and 0.5, the SDBS/16–4–16 mixtures can also reduce the crude oil/water IFT to ultra-low (<10−2 mN/m). When the mineralization is between 5000 mg/L and 20,000 mg/L, the IFT of crude oil/water can be reduced to 3.3 × 10−3 mN/m.Adsorption time, temperature, and liquid-solid ratio have less effect on the IFT of the SDBS/16–4–16 mixture (αSDBS = 0.4) than cationic surfactant 16–4–16. As static adsorption time increases to 24 h, the IFT of the SDBS/16–4–16 mixture only increases from 3.13 × 10−3 mN/m to 4.58 × 10−3 mN/m, while 16–4–16 increases the IFT from 0.121 mN/m to 0.202 mN/m. Furthermore, the SDBS/16–4–16 mixture takes only 10 min to reach dynamic adsorption equilibrium, shorter than the two pure components. The ability of the SDBS/16–4–16 mixtures to reduce the contact angle on the lipophilic glass surface and the oil film peeling-off performance is significantly superior to 16–4–16 and SDBS. As low as 0.1 mmol/L, the SDBS/16–4–16 mixture (αSDBS = 0.4) can reduce the contact angle of oil-wet glass surface from 107° to 46°, while 16–4–16 reduces it to 68° and SDBS to 79°. Eventually, the SDBS/16–4–16 mixture (αSDBS = 0.4) shows excellent performance in the core flooding experiments. The SDBS/16–4–16 mixture could improve crude oil recovery by 26.2%, demonstrating great potential in EOR.

Synthesis and Thermal Stability of Bis-Quaternary Ammonium Ionic Liquids with Inorganic Anions

Synthesis and Thermal Stability of Bis-Quaternary Ammonium Ionic Liquids with Inorganic Anions

Bis-quaternary ammonium betulin-based dimethacrylate: synthesis, characterization, and application in dental restorative resins

Bis-quaternary ammonium betulin-based dimethacrylate derivatives (Bis-QADM-Bet) were synthesized. Regulating the alkyl chain length of Bis-QADM-Bet endows dental resins with superior antibacterial effects and acceptable physicochemical properties.

Study on the epoxidation of olefins with H2O2 catalyzed by biquaternary ammonium phosphotungstic acid

Selective epoxidation of olefins is an important field in chemical industry. In this work, we developed a new phosphotungstic acid catalyst {[(C8H17)(CH3)2N]2(CH2)3}1.5{PO4[WO(O2)2]4} with long carbon chain and biquaternary ammonium cation. Cyclohexene could be epoxidized to cyclohexene oxide in 96.3% conversion and 98.2% selectivity. The catalyst type, solvent type, catalyst loading, initial molar ratio, temperature, cycle performance and substrate extensibility were studied and optimized, the kinetic parameters about overall reaction and unit reaction were also calculated. Dynamic light scattering analysis was carried out to explain the different catalytic performance between catalysts with different carbon chain length. This novel catalyst and the corresponding dynamics and mechanism study could probably help the industrial application on the epoxidation of cyclohexene with H2O2.

Interfacial properties of cationic and anionic Gemini surfactant mixtures

AbstractThe possibility and the prospect of cationic/anionic (“catanionic”) surfactant mixtures based on sulfonate Gemini surfactant (SGS) and bisquaternary ammonium salt (BQAS) in the field of enhanced oil recovery was investigated. The critical micelle concentration (CMC) of SGS/BQAS surfactant mixtures was 5.0 × 10−6 mol/L, 1–2 orders of magnitude lower than neat BQAS or SGS. A solution of either neat SGS or BQAS, could not reach an ultra‐low interfacial tension (IFT); but 1:1 mol/mol mixtures of SGS/BQAS reduced the IFT to 1.0 × 10−3 mN/m at 100 mg/L. For the studied surfactant concentrations, all mixtures exhibited the lowest IFT when the molar fraction of SGS among the surfactant equaled 0.5, indicating optimal conditions for interfacial activity. The IFT between the 1:1 mol/mol SGS/BQAS mixtures and crude oil decreased and then increased with the NaCl and CaCl2 concentrations. When the total surfactant concentration was above 50 mg/L, the IFT of SGS/BQAS mixtures was below 0.01 mN/m at the studied NaCl concentrations. Adding inorganic salt reduced the charges of hydrophilic head groups, thereby making the interfacial arrangement more compact. At the NaCl concentration was above 40,000 mg/L, surfactant molecules moved from the liquid–liquid interface to the oil phase, thus resulting in low interfacial activity. In addition, inorganic salts decreased the attractive interactions of the SGS/BQAS micelles that form in water, decreasing the apparent hydrodynamic radius (DH, app) of surfactant aggregates. When the total concentration of surfactants was above 50 mg/L, the IFT between the SGS/BQAS mixtures and crude oil decreased first and then increased with time. At different surfactant concentrations, the IFT of the SGS/BQAS mixtures attained the lowest values at different times. A high surfactant concentration helped surfactant molecules diffuse from the water phase to the interfacial layer, rapidly reducing the IFT. In conclusion, the cationic‐anionic Gemini surfactant mixtures exhibit superior interfacial activity, which may promote the application of Gemini surfactant.

On the spacer group effect on anti-Escherichia Coli activity of cationic gemini surfactants using molecular connectivity indices and atomic charges

The molecular connectivity indices were used to investigate the effect of the spacer group structure on the value of minimum inhibitory concentration of bis-quaternary ammonium bromide salts. QSAR model obtained allows to examine the influence of branching, multiple bonds, and heteroatoms of the spacer group on minimum inhibitory concentration value. The effect of spacer’s branches and heteroatoms on anti – Escherichia coli activity of cationic gemini surfactants was also investigated using the atomic charges. This study leads to some significant conclusions regarding the effect of the spacer group structure on antibacterial activity of cationic gemini surfactants against Escherichia coli. The general conclusion is that a small modification of the straight spacer chain structure can give gemini surfactant with of excellent activity against such resistant bacterium as Escherichia coli.

Antibacterial dental resin composites (DRCs) with synthesized bis-quaternary ammonium monomethacrylates as antibacterial agents

Three bi-quaternary ammonium methacrylates (biQAMA-12, biQAMA-14, and biQAMA-16) with different alkyl chain length were synthesized with the purpose of endowing dental resin composites (DRCs) with antibacterial activity without sacrificing physicochemical properties of DRCs. All of biQAMAs were confirmed by 1H-NMR spectra and incorporated into Bis-GMA/TEGDMA (60 wt/40 wt) resin matrix with a mass fraction of 5 wt% as antibacterial agent. The obtained resin matrixes were mixed with commercial silaned glass fillers at a mass ratio of 30 wt/70 wt to prepare antibacterial DRCs. The double bond conversion (DC), antibacterial activity against S. mutans., surface charge density, water contact angle, water sorption (WS) and solubility (SL), mechanical properties, and cytotoxicity of biQAMAs containing DRCs were investigated. The DRC without biQAMAs was used as control. The results showed that all biQAMAs containing DRCs had antibacterial rate higher than 90%, and DRC with biQAMA-12 had the highest antibacterial rate due to its highest surface charge density. Adding 5 wt% of biQAMAs would not bring out negative effect on physicochemical properties of DRCs, except for increasing WS, but the resultant WS still met the ISO requirement on WS of restorative materials. Both biQAMA-14 and biQAMA-16 containing DRCs showed higher cytotoxicity than control, thus biQAMA-12 was considered as the optimal antibacterial agent in this research.

Microbiological Evaluation of Novel Bis-Quaternary Ammonium Compounds: Clinical Strains, Biofilms, and Resistance Study.

This work is devoted to the investigation of biocidal properties of quaternary ammonium compounds (QACs) based on pyridine structures with aromatic spacers, and their widely known analogs, against clinically significant microorganisms. This study is focused on investigating their antimicrobial activity (minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs)), antibiofilm properties (minimum biofilm inhibitory concentrations (MBICs) and minimum biofilm eradication concentrations (MBECs)), synergetic effect with different alcohols in antiseptic formulations, and bacterial resistance development. It was shown that all combined analogue preparations had a higher level of antibacterial activity against the tested bacterial strains, with a 16- to 32-fold reduction in MICs and MBCs compared to previously used antiseptic preparations. Moreover, hit-QACs demonstrated a stable effect against Gram-negative E. coli, K. pneumoniae, and A. baumannii within a month of incubation. Overall results indicated a high level of antibacterial activity of pyridine-based QACs.

Tertiary amine-bisquaternary ammonium functionalized polyacrylonitrile fiber for catalytic synthesis of pyran-annulated heterocycles

Polyacrylonitrile fiber supported bisquaternary ammonium salts with varying interchain quaternary ammonium (QA) to tertiary amine (TA) ratio, counter ions and linker groups were prepared and characterized by TGA, FTIR, XPS, XRD, SEM, EA and water contact angle. The functionalized fibers were used to catalyze three-component reaction (3CR) and tandem deacetalization-3CR for the synthesis of pyrano[4,3-b]pyrans, pyrano[3,2-c]chromenes and pyrano[3,2-c]quinolines in ethanol-water mixture. Under varying reaction conditions such as time, temperature, catalyst amount and solvents, the catalytic ability of the prepared fiber catalyst was investigated. Under the optimum conditions, the bisquaternary ammonium fiber with acetate counter ion and an interchain QA to TA ratio of 1:1 (PANBQAcF) showed the best catalytic activity among the prepared fiber catalysts, and it can be used for 10 runs consecutively with only a slight depreciation in catalytic activity. Interestingly, PANBQAcF can efficiently catalyze tandem deacetalization-Knoevenagel reaction and the relevant novel tandem deacetalization-3CRs for the synthesis of pyran-annulated heterocycles. In the tandem deacetalization reactions, the acetate ion plays an important role of facilitating proton transfer, which makes PANBQAcF a cooperative and reusable heterogeneous catalyst.

High performance Mg2+/Li+ separation membranes modified by a bis-quaternary ammonium salt

The separation of lithium (Li+, 3.8 Å) and magnesium (Mg2+, 4.3 Å) ions represents the main challenge for lithium extraction from salt lakes with high magnesium-to‑lithium (Mg2+/Li+) ratio. A bis-quaternary ammonium salt (abbreviated as QEDTP) was designed to modify Polyethyleneimine (PEI) polyamide nanofiltration membrane. Water flux of the modified PEI membrane is 126.9 ± 1.6 L·m−2·h−1 (LMH) under 6 bar hydraulic pressure, which is 4.4 times as high as the pristine PEI membrane (25.8 ± 0.3 LMH). Meanwhile, the MgCl2 rejections of both membranes are maintained >95%. Nanofiltration performance of the QEDTP membrane is stable in 180 h continuous nanofiltration test at 6 bar pressure. The water flux and Mg2+/Li+ selectivity (SMg2+/Li+) of the QEDTP modified membrane in filtrating 2000 ppm Mg2+/Li+ mixture (Mg2+/Li+ ratio: 120:1, 6 bar) are 112.9 ± 1.6 LMH and 15.6 ± 0.3, which is one of the best Mg2+/Li+ separation performance considering both the flux and selectivity.

Development of Antibacterial Dental Resins Containing Bis-Quaternary Ammonium Betulin-Based Dimethacrylate

Development of Antibacterial Dental Resins Containing Bis-Quaternary Ammonium Betulin-Based Dimethacrylate

Enantioselective aza-Michael Cyclization Reaction Catalyzed by Quinine-Derived Monoquaternary Ammonium Salts: an Effective Route to Synthesize Letermovir

A series of mono- or bis-quaternary ammonium salts derived from cinchonidine or quinine was synthesized and screened as potent phase-transfer catalysts for the reaction of aza-Michael cyclization, the key step in the synthesis of letermovir. During the reaction of aza-Michael cyclization, the screened monoquaternary ammonium salt quinine derivative Q1 transferred 7 to 8 with 91.9% yield and 58% ee. The application of Q1 was preferred, due to its enantioselectivity, the possibility of reuse, and the lower cost in large-scale preparation. Furthermore, the racemization condition of letermovir enantiomer was also explored for the possibility to develop the resolution/racemization process. With the optimal catalyst Q1 in hand, the synthesis of letermovir may be more convenient and economical in the future.