Quaternary Ammonium Surfactants Research Articles

Successful complete digestion of well lithified shale and extraction of microfossils from Devonian beds in western New York

ABSTRACT: Researchers in paleontological and paleoecological sciences often need complete disaggregation of rock materials for certain lines of investigation. However, complete disaggregation of more lithified sedimentary rock is known to be problematic. A complete shale disaggregation method implementing quaternary ammonium surfactants,widely used in paleontological sciences for poorly lithified shale and mudstone, was successfully used on well lithified Devonian shale in the Appalachian Basin ofWestern New York. Over 50 Devonian gray and black shale samples were collected from multiple localities in western New York (Cashaqua, Rhinestreet, Skaneateles, Windom, and Ludlowville), coarsely crushed, and fully immersed in a quaternary ammonium surfactant until complete disaggregation was achieved (5–14 days); aliquots were run through a series of nested sieves. The sieved sediments contained hundreds of well-preserved microfossils released from the shale: ostracods, dacryoconarids, and previously unreported palymorphs, charophytes, agglutinated foraminifera, miospores, and other microspherules. These microfossils were easily found within disaggregated and sieved samples but were unrecognizable on the shale surface and destroyed in prior investigations of whole rock thin sections. In addition to more traditional approaches, inclusion of this complete rock disaggregation method may assist in a more complete analysis of material, increase our understandings of ancient basin systems and have important implications on our understanding of the paleoecology during the Late Devonian marine biotic crises.

Study on the Surface Properties and Aggregation Behavior of Quaternary Ammonium Surfactants with Amide Bonds.

A number of techniques, including conductivity, surface tension, dynamic light scattering, transmission electron microscopy, and 1H nuclear magnetic resonance (1H NMR), Fourier transform infrared (FT-IR), and 1H–1H 2D nuclear Overhauser effect spectroscopy (1H–1H 2D NOESY), have been used to investigate the effect of amide bonds on the interfacial and assembly properties of a cationic surfactant, N-anilinoformylmethyl-N-cetyl-N,N-dimethyl ammonium chloride (AMC-C16), in aqueous solutions. The adsorption of AMC-C16 has been found to be much better than that of the conventional cationic surfactant, benzyl cetyldimethylammonium chloride (BAC-16) at the air/water interface and in solution. The surface tension measurements show the presence of two critical aggregation concentrations (CAC1 and CAC2) for AMC-C16. The presence of a strong intermolecular hydrogen bond of AMC-C16 was confirmed by 1H NMR and FT-TR. The molecular interactions of AMC-C16 were detected by 1H–1H 2D NOESY. The results show that the rigid group (phenyl) of AMC-C16 was partially overlapped with its alkyl chain in aqueous solution, and the possible aggregation behavior for AMC-C16 was proposed. The effects of an inorganic salt (NaCl) and an organic salt (C6H5COONa) to the aggregates of AMC-C16 have been discussed.

Hybrid Nanoparticles of Poly (Methyl Methacrylate) and Antimicrobial Quaternary Ammonium Surfactants.

Quaternary ammonium surfactants (QACs) are microbicides, whereas poly (acrylates) are biocompatible polymers. Here, the physical and antimicrobial properties of two QACs, cetyl trimethyl ammonium bromide (CTAB) or dioctadecyl dimethyl ammonium bromide (DODAB) in poly (methyl methacrylate) (PMMA) nanoparticles (NPs) are compared to those of QACs alone. Methyl methacrylate (MMA) polymerization using DODAB or CTAB as emulsifiers and initiator azobisisobutyronitrile (AIBN) yielded cationic, nanometric, homodisperse, and stable NPs. NPs’ physical and antimicrobial properties were assessed from dynamic light scattering (DLS), scanning electron microscopy, and viability curves of Escherichia coli, Staphylococcus aureus, or Candida albicans determined as log(colony-forming unities counting) over a range of [QACs]. NPs were spherical and homodisperse but activity for free QACs was higher than those for QACs in NPs. Inhibition halos against bacteria and yeast were observed only for free or incorporated CTAB in NPs because PMMA/CTAB NPs controlled the CTAB release. DODAB displayed fungicidal activity against C. albicans since DODAB bilayer disks could penetrate the outer glycoproteins fungus layer. The physical properties and stability of the cationic NPs highlighted their potential to combine with other bioactive molecules for further applications in drug and vaccine delivery.

Coupling quaternary ammonium surfactants to the surface of liposomes improves both antibacterial efficacy and host cell biocompatibility

By functionalizing the surface of PEG-liposomes with linkers bearing quaternary ammonium compounds (QACs), we generated novel bacteria disruptors with anti-adhesive properties and reduced cytotoxicity compared to free QACs. Furthermore, QAC-functionalized liposomes are a promising platform for future drug encapsulation. The QAC (11-mercaptoundecyl)-N,N,N-trimethylammonium bromide (MTAB) was attached to maleimide-functionalized liposomes (DSPE-PEG) via thiol linker. The MTAB-functionalized liposomes were physicochemically characterized and their biological activity, in terms of anti-adherence activity and biofilm prevention in Escherichia coli were assessed. The results showed that MTAB-functionalized liposomes inhibit bacterial adherence and biofilm formation while reducing MTAB toxicity.

Modified bentonite by polyhedral oligomeric silsesquioxane and quaternary ammonium salt and adsorption characteristics for dye

To remove methylene blue dye from water by adsorption, bentonites were modified by polyhedral oligomeric silsesquioxane (POSS) and three kind of quaternary ammonium surfactants (dodecyl trimethyl ammonium bromide, tetrabutyl ammonium bromide, cetyl trimethylammonium bromide) in aqueous solution. Systematic adsorption experiments were carried out, the adsorption mechanism was studied, and the factors governing the adsorption of methylene blue on modified bentonite were discussed. The adsorption capacity of methylene blue on all three modified bentonites in 1000 mg·L−1 solutions quickly reached equilibrium within 2000 s, and the removal rate was basically 100%; however, the removal rate in raw bentonite samples was only 60%. The pseudo second-order kinetic model can provide satisfactory kinetic data fitting. The obtained adsorption isotherms fit well with the Dubinin-Radushkevich isotherm model. The thermodynamic results showed that the adsorption process was a spontaneous endothermic physical adsorption process. With increasing pH and KCl concentration, the removal of methylene blue increased significantly. The results of this study confirmed that the modified bentonite is a candidate material as a cationic dye adsorbent.

Syntheses of naphthyl-based quaternary ammonium surfactants and their catalytic properties in chloromethylation of naphthalene

Two naphthyl-based quaternary ammonium surfactants Naph-GS and Naph-MS were synthesized by reaction of bis(chloromethyl)naphthalene and chloromethyl naphthalene with N, N-dimethyl long-chain alkyl tertiary amine. The purified products were characterized by FT-IR and ESI-HRMS. The critical micelle concentration and surface tension (γCMC) at the critical micelle concentration (CMC) of Naph-MS and Naph-GS are 3.70 mmol/L, 27.90 mN/m; 0.89 mmol/L and 31.60 mN/m, respectively. The CMC of Naph-MS is about four times higher than that of Naph-GS. The sizes of most micelles of Naph-MS and Naph-GS aqueous solution at 1.1 CMC are both <1 nm. While at the concentration of 11 CMC, most of the Naph-MS, the Naph-GS micelles aggregate forming particles with an average size of 1.2 nm and 10 nm, respectively. The Naph-MS and Naph-GS were used to promote the chloromethylation reaction of naphthalene. The conversion of naphthalene was 77% when the reaction was catalyzed by Naph-MS (2.5 mol% of naphthalene at 48 mmol/L) at mole ratio of naphthalene/paraformaldehyde/NaCl/H2SO4 being 1.0:1.0:1.7:6.3 at 70 °C for 12 h. At the same condition, the conversion of naphthalene was 82% when the reaction was promoted by Naph-GS (0.53 mol% of naphthalene at 10 mmol/L). When the mole ratio of naphthalene/paraformaldehyde was increased to 1.25, the conversion of naphthalene increased to 90%, and the positioning selectivity (1-chloromethyl to 2-chloromethyl) is 94.8%. The gemini surfactant Naph-GS has better catalytic performance than conventional Naph-MS in the chloromethylation of naphthalene. The inorganic aqueous solution can be recycled by simple separation, and the conversion of naphthalene can still remain at 85% after 5 cycles.

Synthesis and Interfacial Activity of a New Quaternary Ammonium Surfactant as an oil/gas field chemical

Abstract Cationic quaternary ammonium surfactant s are widely applied in many fields, such as detergent, cosmetics, petroleum and natural gas industries. However, the study of the effect of anion on cationic surfactants is rare. To research the influence of anions on the surface properties, a cationic surfactant was prepared, (cetyltrimethyl ammonium isonicotinate, CTAIN), and the surface properties were studied, including surface tension, critical micelle concentration, foaming ability and stability, and corrosion inhibition. The results indicated that the minimum surface tension of CTAIN is lower than that of CTAC, the foaming ability and foaming stability of CTAIN is higher than that of CTAC, and the corrosion inhibition efficiency on mild steel of CTAC is more potent than that of CTAIN. All the results indicate that the new cationic quaternary ammonium surfactant is a useful surfactant in the related fields.

Surface Activities, Antibacterial Activity and Corrosion Inhibition Properties of Gemini Quaternary Ammonium Surfactants with Amido Group and Carboxylic Counterions.

A series of gemini quaternary ammonium surfactants containing carboxylate counterion with the formula C17H35CONH(CH2)2N+(CH3)2(CH2)2N+(CH3)2(CH2)2 NHCO C17H35·2Y (Y=HCOO-, CH3COO-, CH3CHOHCOO-) have been synthesized by a counterion conversion process and characterized by Fourier transform infrared spectroscopy and mass spectroscopy. It is found that these surfactants reduce the surface tension of water to a minimum value of 26.78 mN·m-1 at a concentration of 1.21 ×10-5 mol·L-1. TEM images reveal that aggregates with vesicles or tubular structure are spontaneously formed in these surfactants aqueous solution with the concentration of 1×10-3 mol·L-1. It is also found that they are effective corrosion inhibitors for A3 steel in acid solution and have superior antibacterial activity at a concentration of 0.1g·L-1.

Comprehensive screening of quaternary ammonium surfactants and ionic liquids in wastewater effluents and lake sediments.

Quaternary ammonium compounds (QACs) are widely applied as surfactants and biocides in cleaning and personal-care products. Because of incomplete removal during wastewater treatment, QACs are present in wastewater effluents, with which they are discharged into natural waters, where they accumulate in sediments. To assess the levels of QACs in aquatic environments, a liquid chromatography high-resolution mass spectrometry method using both target and suspect screening was developed. The water and sediment sample preparation, measurement, and data analysis workflow were optimized for 22 target compounds with a wide range of hydrophobicity, including ionic liquids that have potential use as solvents and QACs common in personal-care and sanitizing products. In wastewater effluents, average concentrations of all target and suspect QACs combined ranged from 0.4 μg L-1 to 6.6 μg L-1. Various homologs of benzylalkyldimethylammonium (BAC) and dialkyldimethylammonium (DADMAC) as well as the ionic liquid butylpyridinium and 15 suspect QACs were detected in at least one wastewater effluent sample. A spatial profile of sediment samples in a lake demonstrated potential inputs from both municipal wastewater effluent and agricultural sources for BACs. In sediment cores, two distinct trends of temporal QAC accumulation were observed. In lakes with large watersheds and mixed domestic and industrial wastewater sources (Lake Pepin and Duluth Harbor), peak concentrations of QACs were found at depths corresponding to deposition in the 1980s and decreases after this time are attributed to improved wastewater treatment and source control. In a smaller lake with predominantly domestic wastewater inputs (Lake Winona), concentrations of QACs increased slowly over time until today.

Synthesis and interface activity of a series of carboxylic quaternary ammonium surfactants

Synthesis and interface activity of a series of carboxylic quaternary ammonium surfactants

Front Cover: Highly hydrophilic cationic gold nanorods stabilized by novel quaternary ammonium surfactant with negligible cytotoxicity (J. Biophotonics 12/2019)

Cationic gold nanorods stabilized by quaternary ammonium salts (QAS) are a promising tool for photothermal destruction of cancer cells. However, cytotoxicity of the alkanethiol‐QAS limits their medical applications. A novel design of cationic surfactant composed of the quaternary ammonium group and ethylene glycol chain significantly reduces the compound cytotoxicity in the free state while allowing the preparation of stable nanorods with high cellular uptake and lysosomal localization.Further details can be found in the article by Sarka Salajkova, Michal Sramek, David Malinak, et al. (e201900024). image

Micellar Catalysis Strategy of Cross-Condensation Reaction: The Effect of Polar Heads on the Catalytic Properties of Aminoalcohol-Based Surfactants

The effect of the polar head and the concentration of quaternary ammonium surfactants (C14EtOH, C14iPrOH, C14PrOH, where, 14 = carbon number iPrOH = iso-propanol, EtOH = ethanol, PrOH = propanol) in micellar catalysis for the cross-condensation reaction (Claisen–Schmidt) was investigated. The reaction in the Micellar-NaOH system with different concentrations of surfactants above the critical micelle concentration from 15 to 30 mmol between benzaldehyde and acetophenone was used as a model of reaction for this study. The examination of the effectiveness of the catalytic activity reveals that the compound C14EtOH has the best yield (80% of the desired product), followed by C14iPrOH and C14PrOH. The results were interpreted according to the solubilization capacity, droplet size analysis of reagents (benzaldehyde and acetophenone) in the micellar medium and stability of reaction intermediate (enolate) by the electrostatic interactions generated by positive charge of N+ quaternary ammonium atom. Therefore, the quantum calculations carried out by DFT method for surfactants in the aqueous medium, show that electrophilicity degree and the reaction yield% for three cationic surfactants varies in the same following order: C14PrOH < C14iPrOH < C14EtOH.

Synthesis and Interface Activity of a Series of Carboxylic Quaternary Ammonium Surfactants in Hydraulic Fracturing

Hydraulic fracturing is an important technology for the development of unconventional resources, while the foam fracturing plays an essential role for the oil recovery in hydraulic fracturing. To further explore the anion effect of quaternary ammonium cationic surfactants on their relative performances, four fatty acid surfactants were prepared (cetyltrimethylammonium acetate (CTAAC), cetyltrimethylammonium butyrate (CTABU), cetyltrimethylammonium hexanoate (CTAHE), and cetyltrimethylammonium caprylate (CTACA)). The effect of anions on surface tension and foaming properties were discussed, and the emulsion stability was also investigated. The experimental results were presented that the CTAAC possesses the highest surface activities compared with other members in the prepared surfactants. The critical micelle concentration (CMC) and surface tension at the CMC (γCMC) increase as increasing methylene segments in the anions, the maximum surface excess concentration (Γmax), and minimum area per molecule (Amin) present an opposite trend with the increase of methylene segments. The CTAAC exhibits the best performances on foamability and foam stability than other synthesized surfactants at 70°C; the initial foam height (H0) and the foam height ratio (R3) at 0 min and 3 min are 34.9 cm and 52.9%, respectively; this is due to the lowest surface tension and shortest methylene segments. In addition, the emulsion stability was shown to follow the order of CTAAC&gt;CTABU&gt;CTAHE&gt;CTACA.

Synergistic effect of hen egg white lysozyme and lysosomotropic surfactants on cell viability and membrane permeability

The interactions between two types of quaternary ammonium surfactants (N,N,N-trimethyl-2-(dodecanoyloxy)ethaneammonium bromide (DMM-11) and N,N,N-trimethyl-2-(dodecanoyloxy)propaneammonium bromide (DMPM-11)) and hen egg white lysozyme were studied through several techniques, including isothermal titration calorimetry (ITC), circular dichroism (CD) and fluorescence spectroscopy, and surface tension measurement. The average number of surfactants interacting with each molecule of lysozyme was calculated from the biophysical results. Moreover, the CD results showed that the conformation of lysozyme changed in the presence of DMM-11 and DMPM-11. The studies drew a detailed picture on the physicochemical nature of interactions between both surfactants and lysozyme. Both DMM-11 and DMPM-11, with and without lysozyme were studied against three target microorganisms, including Gram-negative (Escherichia coli) and Gram-positive (Enterococcus hirae and Enterococcus faecalis) bacteria. The results revealed a broad spectrum of antibacterial nature of surfactant/lysozyme complexes, as well as their effect on the membrane damage, hence providing the basis to further explore DMM-11 and DMPM-11 combined with lysozyme as possible antibacterial tools.

Effect of Divalent Cation on Swelling Behavior of Anionic Microgels: Quantification and Dynamics of Ion Uptake and Release

Poly(N-vinylcaprolactam-co-itaconate) (P(VCL-co-IADME) microgels were synthesized varying the molar ratio between VCL and IADME via free radical precipitation polymerization in the presence of quaternary ammonium surfactant. In order to determine the effect of the divalent metal ions on the structure and the swelling behavior of the microgel systems, both neutral and charged forms of the hydrogels after hydrolysis were investigated. The triggered gel collapse caused by the divalent metal ion together with the quantification of the metal ion uptake was studied in detail by titration and ion chromatography methods and revealed the minimum concentration around 0.1 mM to trigger gel collapse on the treated gels. Uptake and release dynamics of the gels were followed by turbidity measurements and were in the time-range of 2 and 17 s, depending on the composition and the concentrations.

The Aggregation Behavior and Antioxidative Activity of Amphiphilic Surfactants Based on Quinuclidin‐3‐ol

AbstractThe self‐aggregation and thermodynamic properties of three cationic quaternary ammonium surfactants were investigated. The physicochemical properties of compounds containing quinuclidin‐3‐ol with even number of carbon atoms (10, 12, and 14) in the hydrophobic tail were measured by conductivity, dynamic light scattering (DLS), and Zeta‐potential measurements. DLS and Zeta‐potential measurements show a similar size distribution for all surfactants with excellent uniformity, and Zeta‐potential increases significantly with increase in the size of hydrocarbon tail. The critical micelle concentration (CMC) and the degree of micelle ionization (β) were determined using conductivity measurements. The CMC values of surfactants were found to be between 3.4 and 23.8 × 10−3 M. The standard Gibbs free energy () was derived from conductivity measurements and suggests that surfactants containing longer chains spontaneously form micelles. The antioxidative properties of these cationic surfactants were evaluated using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) assays. Among the tested samples, N‐tetradecyl‐3‐hydroxyquinuclidinium bromide (QOH‐C14) exhibited the highest antioxidative potential (388.30 nmol (TE) equivalents mL−1), which was further investigated by the DNA nicking assay.

The surface adsorption, aggregate structure and antibacterial activity of Gemini quaternary ammonium surfactants with carboxylic counterions.

A group of Gemini quaternary ammonium surfactants with the formula CnH2n+1CONH(CH2)2N+(CH3)2(CH2)2N+(CH3)2(CH2)2 NHCOCnH2n+1 · 2Y (n = 11, 13 and 15, Y = HCOO−, CH3COO− and CH3CHOHCOO−) have been synthesized by a counterion conversion process and characterized by Fourier transform infrared spectroscopy and mass spectroscopy. Their adsorption and self-aggregation properties are investigated by surface tension, conductivity, dynamic light scattering and transmission electron microscopy (TEM) measurements. The results show that these surfactants reduce the surface tension of water to a minimum value of 26.51 mN m−1 at a concentration of 5.72 × 10−2 mmol l−1. Furthermore, the increased alkyl chain length of the carboxylic counterions leads to the increased critical micelle concentration, the decreased degree of counterion binding (β) and the decreased self-assembly tendency, but the minimum area per surfactant molecule (Amin) adsorbed at the air–aqueous solution are similar. TEM images reveal that these surfactants self-assemble spontaneously into aggregates with vesicle or bilayer structures. It is also found that they have superior antibacterial activity at a concentration of 0.1 g l−1. The high surface activity and high antibacterial activity of the Gemini quaternary ammonium salt surfactants containing different carboxylic counterions bring more possibilities for the application in the field of biomedicine.

Cetrimonium Bromide Inhibits Cell Migration and Invasion of Human Hepatic SK-HEP-1 Cells Through Modulating the Canonical and Non-canonical TGF-β Signaling Pathways.

Cetrimonium bromide (CTAB), a quaternary ammonium surfactant, is an antiseptic agent against bacteria and fungi. However, the mechanisms by which its pharmacological actions affect epithelial-mesenchymal transition (EMT) in hepatocellular carcinoma (HCC) cells, such as adenocarcinoma in SK-HEP-1 cells, have not been investigated. We, thereby, investigated whether CTAB inhibits cellular mobility and invasiveness of human hepatic adenocarcinoma in SK-HEP-1 cells. SK-HEP-1 cells were treated with CTAB, and subsequent migration and invasion were measured by wound healing and transwell assays. Protein expression was detected by immunoblotting analysis. Our data revealed that treatment of SK-HEP-1 cells with CTAB altered their mesenchymal spindle-like morphology. CTAB exerted inhibitory effects on the migration and invasion of SK-HEP-1 cells dose-dependently, and reduced protein levels of matrix metalloproteinase-2 (MMP-2), MMP-9, snail, slug, twist, vimentin, fibronectin, N-cadherin, Smad2, Smad3, Smad4, phosphoinositide-3-kinase (PI3K), p-PI3K, Akt, p-Akt, β-catenin, mammalian target of rapamycin (mTOR), p-mTOR, p-p70S6K, p-extracellular signal-regulated kinases (ERK)1/2, p-p38 mitogen-activated protein kinase (MAPK) and p-c-Jun N-terminal kinase (JNK), but increased protein levels of tissue inhibitor matrix metalloproteinase-1 (TIMP-1), TIMP-2, claudin-1 and p-GSK3β. Based on these observations, we suggest that CTAB not only inhibits the canonical transforming growth factor-β (TGF-β) signaling pathway though reducing SMADs (an acronym from the fusion of Caenorhabditis elegans Sma genes and the Drosophila Mad, Mothers against decapentaplegic proteins), but also restrains the non-canonical TGF-β signaling including MAPK pathways like ERK1/2, p38 MAPK, JNK and PI3K. CTAB is involved in the suppression of TGF-β-mediated mesenchymal phenotype and could be a potent medical agent for use in controlling the migration and invasion of hepatic adenocarcinoma.

Quaternary Ammonium Leucine-Based Surfactants: The Effect of a Benzyl Group on Physicochemical Properties and Antimicrobial Activity.

Quaternary ammonium amphiphiles are a class of compounds with a wide range of commercial and industrial uses. In the pharmaceutical field, the most common quaternary ammonium surfactant is benzalkonium chloride (BAC), which is employed as a preservative in several topical formulations for ocular, skin, or nasal application. Despite the broad antimicrobial activity against Gram-positive and Gram-negative bacteria, as well as fungi and small enveloped viruses, safety concerns regarding its irritant and cytotoxic effect on epithelial cells still remain. In this work, quaternary ammonium derivatives of leucine esters (C10, C12 and C14) were synthesised as BAC analogues. These cationic surfactants were characterised in terms of critical micelle concentration (CMC, by tensiometry), cytotoxicity (MTS and LDH assays on the Caco-2 and Calu-3 cell lines) and antimicrobial activity on the bacterial species Staphylococcus aureus and Enterococcus faecalis among the Gram-positives, Escherichia coli and Pseudomonas aeruginosa among the Gram-negatives and the yeast Candida albicans. They showed satisfactory surface-active properties, and a cytotoxic effect that was dependent on the length of the hydrophobic chain. Lower minimum inhibiting concentration (MIC) values were calculated for C14-derivatives, which were comparable to those calculated for BAC toward Gram-positive bacteria and slightly higher for Gram-negative bacteria and C. albicans. Thus, the synthesised leucine-based quaternary ammonium cationic surfactants can potentially find application as promising surface-active compounds with antimicrobial activity.

Fatty Acid Quaternary Ammonium Surfactants Based on Renewable Resources as a Leveler for Copper Electroplating

AbstractInvited for this month's cover picture is the group of Prof. Limin Wang from East China University of Science and Technology (China). The cover picture shows a new leveler for copper electroplating from fatty acid quaternary ammonium surfactant, which is based on renewable resources. Electrochemical evaluation shows that, at the same concentration, the new leveler has excellent inhibition of electrodeposition, whereas the commercial leveler Janus Green B only weakly inhibits the electrodeposition process. Read the full text of the Article at 10.1002/celc.201900116.