Journal articles: 'Cationic surfactant CTAB'

1

Desai, Tejas R., and Sharad G. Dixit. "Adsorption from Mixtures of Cationic/Non-Ionic Surfactants on to a Polystyrene Surface." Adsorption Science & Technology 15, no. 5 (May 1997): 391–405. http://dx.doi.org/10.1177/026361749701500507.

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The adsorption of cetyltrimethylammonium bromide (CTAB) and nonyl phenyl ethoxylates (NP-n, where n = 13, 20 and 30) on to polystyrene powder has been studied. Concentrations of surfactant solutions ranging from below CMC to well above CMC were investigated. In a single surfactant system, only the cationic surfactant (CTAB) was found to adsorb appreciably while nonionic surfactants showed negligible adsorption. In mixed surfactant systems, the cationic surfactant was found to induce significant co-adsorption of non-ionic surfactants. The increased adsorption of non-ionic surfactants has been attributed to the formation of non-ideal mixed hemimicelles due to intercomponent lateral interactions. However, non-ionic surfactants with longer hydrophilic chains did not form mixed hemimicelles with CTAB. In general, zeta potential measurements support the adsorption results.

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Hosseinzadeh, Reza, Mohammad Gheshlagi, Rahele Tahmasebi, and Farnaz Hojjati. "Spectrophotometric study of interaction and solubilization of procaine hydrochloride in micellar systems." Open Chemistry 7, no. 1 (March 1, 2009): 90–95. http://dx.doi.org/10.2478/s11532-008-0078-4.

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AbstractThe interaction of Procaine hydrochloride (PC) with cationic, anionic and non-ionic surfactants; cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS) and triton X-100, were investigated. The effect of ionic and non-ionic micelles on solubilization of Procaine in aqueous micellar solution of SDS, CTAB and triton X-100 were studied at pH 6.8 and 29°C using absorption spectrophotometry. By using pseudo-phase model, the partition coefficient between the bulk water and micelles, Kx, was calculated. The results showed that the micelles of CTAB enhanced the solubility of Procaine higher than SDS micelles (Kx = 96 and 166 for SDS and CTAB micelles, respectively) but triton X-100 did not enhanced the solubility of drug because of weak interaction with Procaine. From the resulting binding constant for Procaine-ionic surfactants interactions (Kb = 175 and 128 for SDS and CTAB surfactants, respectively), it was concluded that both electrostatic and hydrophobic interactions affect the interaction of surfactants with cationic procaine. Electrostatic interactions have a great role in the binding and consequently distribution of Procaine in micelle/water phases. These interactions for anionic surfactant (SDS) are higher than for cationic surfactant (CTAB). Gibbs free energy of binding and distribution of procaine between the bulk water and studied surfactant micelles were calculated.

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Aramaki, Kenji, Eriko Takimoto, and Takumi Yamaguchi. "Effect of the Cationic Head Group on Cationic Surfactant-Based Surfactant Mediated Gelation (SMG)." International Journal of Molecular Sciences 21, no. 21 (October 28, 2020): 8046. http://dx.doi.org/10.3390/ijms21218046.

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The surfactant-mediated gelation (SMG) method allows us to formulate hydrogels using a water-insoluble organogelator. In this study, we formulated hydrogels using three cationic surfactants, hexadecyltrimethylammonium bromide (CTAB), hexadecyltrimethylammonium chloride (CTAC), and hexadecylpyridinium chloride (CPC)] and an organogelator (12-hydroxyoctadecanoic acid (12-HOA), and studied their structures and mechanical properties. A fiber-like structure similar to that found in the 12-HOA-based organogels was observed by optical microscopy. Small- and wide-angle X-ray scattering profiles showed Bragg peaks derived from the long- and short-spacing of the crystalline structures in the gel fibers and a correlation peak from the surfactant micelles in the small-angle region. Furthermore, the formation of micelles in the hydrogels was confirmed by UV-vis spectroscopic measurements of the gel samples in the presence of Rhodamine 6G. We concluded that the hydrogels prepared by the SMG method in the present systems are orthogonal molecular assembled systems in which two different molecular assembled structures coexist. Among the three surfactant systems, the CTAB system presented the lowest critical gelation concentration and highest sol-gel transition temperature and viscoelasticity. These differences in gel fiber formation and gel properties were discussed from the viewpoint of the degree of solubilization of the gelator molecules in micelles coexisting with gel fibers and diffusion of the gelator molecules in the gel formation process.

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Yehia, Ahmed, Asem A. Atia, and Badr G. Ateya. "Comparative Adsorption of Cationic and Anionic Surfactants on Fluorite." Adsorption Science & Technology 16, no. 6 (June 1998): 431–38. http://dx.doi.org/10.1177/026361749801600602.

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The adsorption behaviours of cetyltrimethylammonium bromide (CTAB) and dioctyl sodium sulphosuccinate (AOT) on fluorite mineral were analyzed as examples of the adsorption of cationic and anionic surfactants on salt-type minerals. Although both surfactants gave adsorption densities well below the monolayer capacity, there were considerable differences between the behaviours of the two surfactants. Thus, while the adsorption density of CTAB increased to a plateau value, that of AOT increased to a maximum before decreasing to very low values at high equilibrium concentrations of the surfactant. Analysis of the behaviour of the surfactants was made using a modified version of the Frumkin adsorption isotherm, taking into account the cross-sectional area of the adsorbed surfactant species and the lateral interaction between their long hydrocarbon chains. The values of the free energy change indicated that both CTAB and AOT underwent adsorption via a physical process, while the lateral interaction coefficient was found to be twice as large in the case of AOT as for CTAB for small or moderate coverage. This latter behaviour was attributed to the fact that while CTAB possesses only one hydrocarbon chain per molecule, AOT has two such chains.

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Kuang, Yu, Xiaoping Zhang, and Shaoqi Zhou. "Adsorption of Methylene Blue in Water onto Activated Carbon by Surfactant Modification." Water 12, no. 2 (February 21, 2020): 587. http://dx.doi.org/10.3390/w12020587.

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In this paper, the enhanced adsorption of methylene blue (MB) dye ion on the activated carbon (AC) modified by three surfactants in aqueous solution was researched. Anionic surfactants—sodium lauryl sulfate (SLS) and sodium dodecyl sulfonate (SDS)—and cationic surfactant—hexadecyl trimethyl ammonium bromide (CTAB)—were used for the modification of AC. This work showed that the adsorption performance of cationic dye by activated carbon modified by anionic surfactants (SLS) was significantly improved, whereas the adsorption performance of cationic dye by activated carbon modified by cationic surfactant (CTAB) was reduced. In addition, the effects of initial MB concentration, AC dosage, pH, reaction time, temperature, real water samples, and additive salts on the adsorption were studied. When Na+, K+, Ca2+, NH4+, and Mg2+ were present in the MB dye solution, the effect of these cations was negligible on the adsorption (<5%). The presence of NO2- improved the adsorption performance significantly, whereas the removal rate of MB was reduced in the presence of competitive cation (Fe2+). It was found that the isotherm data had a good correlation with the Langmuir isotherm through analyzing the experimental data by various models. The dynamics of adsorption were better described by the pseudo-second-order model and the adsorption process was endothermic and spontaneous. The results showed that AC modified by anionic surfactant was effective for the adsorption of MB dye in both modeling water and real water.

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Sakač, Nikola, Dean Marković, Bojan Šarkanj, Dubravka Madunić-Čačić, Krunoslav Hajdek, Božo Smoljan, and Marija Jozanović. "Direct Potentiometric Study of Cationic and Nonionic Surfactants in Disinfectants and Personal Care Products by New Surfactant Sensor Based on 1,3-Dihexadecyl−1H-benzo[d]imidazol−3-ium." Molecules 26, no. 5 (March 4, 2021): 1366. http://dx.doi.org/10.3390/molecules26051366.

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A novel, simple, low-cost, and user-friendly potentiometric surfactant sensor based on the new 1,3-dihexadecyl−1H-benzo[d]imidazol−3-ium-tetraphenylborate (DHBI–TPB) ion-pair for the detection of cationic surfactants in personal care products and disinfectants is presented here. The new cationic surfactant DHBI-Br was successfully synthesized and characterized by nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR) spectrometry, liquid chromatography–mass spectrometry (LC–MS) and elemental analysis and was further employed for DHBI–TPB ion-pair preparation. The sensor gave excellent response characteristics for CTAB, CPC and Hyamine with a Nernstian slope (57.1 to 59.1 mV/decade) whereas the lowest limit of detection (LOD) value was measured for CTAB (0.3 × 10−6 M). The sensor exhibited a fast dynamic response to dodecyl sulfate (DDS) and TPB. High sensor performances stayed intact regardless of the employment of inorganic and organic cations and in a broad pH range (2−11). Titration of cationic and etoxylated (EO)-nonionic surfactant (NSs) (in Ba2+) mixtures with TPB revealed the first inflexion point for a cationic surfactant and the second for an EO-nonionic surfactant. The increased concentration of EO-nonionic surfactants and the number of EO groups had a negative influence on titration curves and signal change. The sensor was successfully applied for the quantification of technical-grade cationic surfactants and in 12 personal care products and disinfectants. The results showed good agreement with the measurements obtained by a commercial surfactant sensor and by a two-phase titration. A good recovery for the standard addition method (98–102%) was observed.

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Cheng, Chao, and Shi-Yong Ran. "Interaction between DNA and Trimethyl-Ammonium Bromides with Different Alkyl Chain Lengths." Scientific World Journal 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/863049.

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The interaction betweenλ—DNA and cationic surfactants with varying alkyl chain lengths was investigated. By dynamic light scattering method, the trimethyl-ammonium bromides-DNA complex formation was shown to be dependent on the length of the surfactant’s alkyl chain. For surfactants with sufficient long alkyl chain (CTAB, TTAB, DTAB), the compacted particles exist with a size of ~60–110 nm at low surfactant concentrations. In contrast, high concentration of surfactants leads to aggregates with increased sizes. Atomic force microscope scanning also supports the above observation. Zeta potential measurements show that the potential of the particles decreases with the increase of surfactant concentration (CTAB, TTAB, DTAB), which contributes much to the coagulation of the particles. For OTAB, the surfactant with the shortest chain in this study, it cannot fully neutralize the charges of DNA molecules; consequently, the complex is looser than other surfactant-DNA structures.

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Kuan, Wen-Hui, Yu-Jung Liu, and Ching-Yao Hu. "Effects of Surfactants on the Degradation of Diclofenac by Manganese Oxide." International Journal of Environmental Research and Public Health 17, no. 12 (June 23, 2020): 4513. http://dx.doi.org/10.3390/ijerph17124513.

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Amine-containing pharmaceuticals are the most often detected pharmaceuticals in wastewater and ambient aquatic environments. They can usually be degraded by manganese oxide (MnO2), which is a common natural oxidant in soils. Surfactants often coexist with pharmaceuticals in wastewater. Some amine-containing pharmaceuticals, such as diclofenac (DIC), are acidic and are thus ionic compounds in neutral conditions. These compounds, therefore, have similar properties to surfactants. Surfactants, thus, may influence the adsorption and degradation processes of DIC by MnO2. The effect of the type of surfactant on the degradation of DIC by MnO2 was investigated in this study with the addition of two common biodegradable surfactants (cetyltrimethyl-ammonium bromide (CTAB) and sodium dodecylsulfate (SDS)). The results indicated that the cationic surfactant (CTAB) significantly increased the degradation rate in neutral and alkaline conditions. On the other hand, the anionic surfactant (SDS) slightly increased the DIC removal rate in an acidic condition but significantly decreased the removal in neutral and alkaline conditions. Coexisting cationic surfactants not only influenced the kinetics but also altered the transformation mechanism of DIC by MnO2. Decarboxylation is the main transformation mechanism of DIC in the presence of CTAB, while both decarboxylation and hydroxylation are the main transformation mechanisms in the absence of CTAB.

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9

Khanal, Manoj. "Study of Methyl Orange-Cetyltrimethyl Ammonium Bromide Interaction by Conductivity Method in Methanol-Water Mixed Solvent Media." International Journal of Applied Sciences and Biotechnology 5, no. 2 (June 29, 2017): 172–79. http://dx.doi.org/10.3126/ijasbt.v5i2.17622.

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The interaction of an anionic dye (Methyl Orange) with cationic surfactant (Cetyltrimethylammonium Bromide, CTAB) in the series of solvent containing variable compositions of methanol-water mixture (10%, 20%, 30% and 40%) was studied at room temperature (31±2oC). Conductivity measurements were done for the investigation of interaction of dyes. The specific conductance of 6.58x10-5 M to 59.22x10-5M surfactant (CTAB) and these surfactants with 1.008x10-3M dye (MO) mixtures were noted at room temperature. A theoretical model was used to calculate conductance ratio from the data of measured specific conductance values. Values of conductance ratio of CTAB-MO mixtures were found to be all less than 1 which indicated that CTAB-MO dye -surfactant mixture exert significant influence on the degree of interaction.Int. J. Appl. Sci. Biotechnol. Vol 5(2): 172-179

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Salimi, E., J. Javadpour, and M. Anbia. "Template-Based Synthesis of Nanoporous Hydroxyapatite." ISRN Ceramics 2012 (October 17, 2012): 1–6. http://dx.doi.org/10.5402/2012/960915.

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Hydroxyapatite (HAp) particles, a potential starting material for bone substitutes, with nanopores were synthesized in the presence of cetyltrimethylammonium bromide (CTAB) and P123 as cationic and nonionic surfactants as the structuring units. Effect of nonionic surfactant concentration on surface areas is also investigated. Based on N2 adsorption-desorption isotherms investigation, surface area increased up to 50 m2/g by using P123 and 147 m2/g by using CTAB as porosity agent. Pore structure remained even after the removal of surfactant and calcinations at 400°C.

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11

Bai, Yun, Jie Zhang, Sanbao Dong, Shidong Zhu, Manxue Wang, Ya Wu, Chunsheng Pu, and Gang Chen. "The Effect of Halide Counter Ions and Methanol on the Foaming Behavior of Cationic Surfactants and a Mechanism Study." Tenside Surfactants Detergents 58, no. 4 (July 1, 2021): 278–86. http://dx.doi.org/10.1515/tsd-2020-2256.

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Abstract In this work, four quaternary ammonium cationic surfactants including cetyltrimethyl ammonium fluoride (CTAF), cetyltrimethyl ammonium chloride (CTAC), cetyltrimethyl ammonium bromide (CTAB) and cetyltrimethyl ammonium iodide (CTAI) were investigated to study the effect of halide anions on the surface activity and foaming performance. The result showed that CTAF had superior surface activity, which could reduce the surface tension of water to 33.15 mN/m at a low CMC (critical micelle formation concentration) of 1.65 mmol/L. Based on the calculation of Amin (the minimum occupied area per surfactant molecule), we assumed that this higher surface activity was related to the small ionic radius of the fluorine ion (F–). The foamability and foam stability of CTAF has great advantages over other surfactants studied. On this basis, the factors affecting the formation and stabilization of the CTAF foam were investigated. The results showed that foam formation benefited from high temperatures and low methanol concentration, while high salinity was beneficial for foam stability. When CTAF at a concentration of 0.2% was used as a foaming agent, foaming was excellent at a methanol concentration of 10%, a salinity of 22 ⨯ 104 mg/L, and a temperature of 90°C. With this study, uncertainties that existed in the literature regarding the effect of anion on surface activity and foam performance were explained and the effect of temperature, methanol and salinity on foam generation and stabilization was understood.

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Rahman, Mohammad Mijanur, M. Yousuf A. Mollah, M. Muhibur Rahman, and Md Abu Bin Hasan Susan. "Electrochemical Behavior of Malachite Green in Aqueous Solutions of Ionic Surfactants." ISRN Electrochemistry 2013 (September 30, 2013): 1–10. http://dx.doi.org/10.1155/2013/839498.

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Electrochemical behavior of malachite green (MG) oxalate in aqueous solution was studied in the presence of a cationic surfactant, cetyltrimethylammonium bromide (CTAB), and an anionic surfactant, sodium dodecyl sulfate (SDS) at a glassy carbon electrode using cyclic voltammetry. The electrochemical oxidation of MG has been characterized as an electrochemically irreversible diffusion-controlled process. Oxidative peak current sharply decreased with increasing SDS concentration, while a slight increase with increasing [CTAB] was apparent. The apparent diffusion coefficient, the surface reaction rate constant, and the electron transfer coefficient of MG clearly show correlation of the electrochemical behavior with the dissolved states of the surfactants. Electrochemical observations together with spectrophotometric results at varying surfactant concentrations provide evidence of interaction of MG with the surfactants to varying extent depending on the type of the surfactant and the concentration.

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Reddy, M. C. Somasekhara, S. M. Sarvar Jahan, K. Sridevi, and G. V. Subba Reddy. "Investigations on Natural Surfactant obtained from Soap-Nuts through Spectrophotometric Interactions with Congo Red and Comparison with Commercial Surfactants." Asian Journal of Chemistry 31, no. 4 (February 27, 2019): 907–16. http://dx.doi.org/10.14233/ajchem.2019.21849.

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A natural surfactant (NS) of plant-base was obtained from the fruit pericarp of soapnuts by using a simple and economical method. The interaction of this natural surfactant with direct dye, anionic dye, Congo red (CR) was studied spectrophotometrically in sub-micellar and micelle concentration range in aqueous solution. These interactions (CR-NS) were compared with that of CR-CTAB (cationic surfactant-cetyl trimethylammonium bromide, CTAB), CR-SDS (anionic surfactant-sodium dodecyl sulphate, SDS) and CR-TX 100 (neutral surfactant - Triton X-100, TX 100) and were useful to understand the nature of natural surfactant. The mechanism of formation of complex due to interactions between Congo red and natural surfactant was suggested. This spectrophotometric method was used for the determination of critical micelle concentration (CMC), at which the formation of micelles was started. The CMC values obtained spectrophotometrically for the natural surfactant was coincided with the experimental value available in the literature. A definite change in the absorbance maxima of Congo red in the presence of natural surfactant (micelles of natural surfactant) was also observed. The change in maxima was also interpreted in terms of pH and CMC. The equilibrium constant of interaction between Congo red and natural surfactant was calculated on the theoretical model. The stability of the complexes of Congo red with different surfactants like CTAB, SDS, TX 100 and natural surfactant may be written in increasing order as: CR-TX 100 > CR-CTAB > CR-NS > CR-SDS. The biodegradable, non-toxic, inexpensive, environmental friendly, renewable natural surfactant was suggested in place of synthetic surfactants.

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Mezei, Amalia, and Ramon Pons. "MWNTs or PEG as Stability Enhancers for DNA–Cationic Surfactant Gel Particles." International Journal of Molecular Sciences 22, no. 16 (August 16, 2021): 8801. http://dx.doi.org/10.3390/ijms22168801.

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Cationic surfactants interact with DNA (Deoxyribonucleic acid), forming surfactant-DNA complexes that offer particularly efficient control for encapsulation and release of DNA from DNA gel particles. In the present work, DNA-based particles were prepared using CTAB (Cetyltrimethylammonium bromide) as the cationic surfactant and modified using two different additives: (Multi-Walled Carbon Nanotubes) MWNT or PEG (Poly Ethylene Glycol). The use of both additives to form composites increased the stability of the gel particles. The stability was monitored by the release of DNA and CTAB in different pH solutions. However, not much is known about the influence of pH on DNA–surfactant interaction and the release of DNA and surfactant from gel particles. It was observed that the solubilization of DNA occurs only in very acid media, while that of CTAB does not depend on pH and gets to a plateau after about 8 h. Within 2 h in contact with a pH = 2 solution, about 1% DNA and CTAB was released. Complete destruction for the gel particles was observed in pH = 2 solution after 17 days for PEG and 20 days for MWNT. The composite particles show a considerably enlarged sustained release span compared to the unmodified ones. The dehydration-rehydration studies show that the structure of the composite gel particles, as determined from SAXS (Small-Angle-X-Ray-Scattering) experiments, is similar to that of the unmodified ones. These studies will allow a better knowledge of these particles’ formation and evolution in view of possible applications in drug delivery and release.

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Yilma, Qidist, Dunkana Negussa, and Y. Dominic Ravichandran. "Effect of Cationic/Anionic Mixed Micelles on Reaction Kinetics of Alkaline Hydrolysis of Crystal Violet." Asian Journal of Chemistry 31, no. 3 (2019): 651–55. http://dx.doi.org/10.14233/ajchem.2019.21701.

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Kinetics of alkaline hydrolysis of crystal violet, a triphenylmethane dye in the micellar environment of cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfonate (SDS) and binary mixtures of these surfactants was studied. The regression parameters, together with rate constants and binding constants were obtained by analyzing the rate surfactant profiles using cooperativity model. It was observed that the reaction was catalyzed by both surfactants. The catalytic factor increased by 10 times in SDS and 38 times in CTAB indicating that binding of crystal violet to the micellar surface is stronger in pure CTAB than SDS but the strength drastically reduced in the mixtures of the surfactants. Reduction of binding constant became more important as the mole fraction of CTAB was improved in the mixture. The kinetic data were investigated using Piszkiewicz model and Raghavan-Srinivasan model. The data obtained from the models were in good agreement with the experimental values.

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Kochkodan, Olga, Nadiya Antraptseva, and Viktor Kochkodan. "Mixed Adsorption of Cetyltrimethylammonium Bromide and Triton X-100 Surfactants on Carbon Black." Materials Science Forum 936 (October 2018): 8–13. http://dx.doi.org/10.4028/www.scientific.net/msf.936.8.

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Adsorption of cationic cetyltrimethylammonium bromide (CTAB) and nonionic Triton X100 surfactants from their mixed aqueous solutions on graphitized carbon black (CB) have been studied. The adsorption isotherms of CTAB or Triton X100 from single solutions on CB surface shown to be of the Langmuir type. In the mixed solutions of CTAB and Triton X100 surfactants, the adsorption of CTAB or Triton X100 on CB decreased in the presence of the other surfactant due to competitive adsorption of the components. It was shown that the mole fraction of Triton X-100 on CB surface has been essentialy changed depending on total concentration of the surfactants mixture. At mixture concentration corresponding to the unsaturated monolayer, a strong synergetic effect was found when the surface excess concentration Triton X100 at the CB surface in the presence of CTAB is higher than that for Triton X-100 in the absence of CTAB.

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Roslyk, Iryna, Ganna Stovpchenkoko, and Galyna Galchenko. "Influence of Surfactants on Copper-CNTs Electrodeposition." Chemistry & Chemical Technology 15, no. 1 (February 15, 2021): 125–31. http://dx.doi.org/10.23939/chcht15.01.125.

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Influence of different types of surfactants on electrodeposition of copper- and carbon-bearing (graphite, carbon nanotubes (CNTs)) composite powder has been experimentally investigated. The size of powder particles decreased, and corrosion resistance increased when surfactants were added. Addition of cationic surfactant CTAB to the electrolyte with simultaneous ultrasonic treatment for CNTs dispersion gives maximum effect.

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Avramova, Tatyana, Lilyana Stefanova, Blaga Angelova, and Sava Mutafov. "Bacterial Decolorization of Acid Orange 7 in the Presence of Ionic and Non-Ionic Surfactants." Zeitschrift für Naturforschung C 62, no. 1-2 (February 1, 2007): 87–92. http://dx.doi.org/10.1515/znc-2007-1-216.

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The effects of the non-ionic surfactant Triton® X-100, the cationic surfactant cetyltrimethylammonium bromide (CTAB) and the anionic surfactant sodium N-lauroyl sarcosinate (SLS) on the decolorization of the reaction medium containing the monoazo dye Acid Orange 7 (AO7) by Alcaligenes faecalis and Rhodococcus erythropolis were studied. It was found that the surfactants influenced in different ways the rate of decolorization. At all concentrations tested the non-ionic surfactant Triton X-100 decreased the decolorization rate of R. erythropolis. At concentrations above the critical micelle concentration (CMC) Triton X-100 upset the usually observed exponential decay of the dye with A. faecalis due probably to the existence of an outer membrane in this organism. In concentrations above the CMC the anionic surfactant SLS inhibited the decolorization and, at prolonged incubation, caused partial release of the bound dye. The cationic surfactant CTAB in concentrations above and below the CMC accelerated drastically the binding of AO7 to the cells causing a rapid staining of the biomass and complete decolorization of the reaction medium. An attempt was made for explanation of the observed differences by the negative electrostatic charge of the living bacterial cell.

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Silva, Amélia, Carlos Martins-Gomes, Tiago Coutinho, Joana Fangueiro, Elena Sanchez-Lopez, Tatiana Pashirova, Tatiana Andreani, and Eliana Souto. "Soft Cationic Nanoparticles for Drug Delivery: Production and Cytotoxicity of Solid Lipid Nanoparticles (SLNs)." Applied Sciences 9, no. 20 (October 19, 2019): 4438. http://dx.doi.org/10.3390/app9204438.

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The surface properties of nanoparticles have decisive influence on their interaction with biological barriers (i.e., living cells), being the concentration and type of surfactant factors to have into account. As a result of different molecular structure, charge, and degree of lipophilicity, different surfactants may interact differently with the cell membrane exhibiting different degrees of cytotoxicity. In this work, the cytotoxicity of two cationic solid lipid nanoparticles (SLNs), differing in the cationic lipids used as surfactants CTAB (cetyltrimethylammonium bromide) or DDAB (dimethyldioctadecylammonium bromide), referred as CTAB-SLNs and DDAB-SLNs, respectively, was assessed against five different human cell lines (Caco-2, HepG2, MCF-7, SV-80, and Y-79). Results showed that the cationic lipids used in SLN production highly influenced the cytotoxic profile of the particles, with CTAB-SLNs being highly cytotoxic even at low concentrations (IC50 < 10 µg/mL, expressed as CTAB amount). DDAB-SLNs produced much lower cytotoxicity, even at longer exposure time (IC50 from 284.06 ± 17.01 µg/mL (SV-80) to 869.88 ± 62.45 µg/mL (MCF-7), at 48 h). To the best of our knowledge, this is the first report that compares the cytotoxic profile of CTAB-SLNs and DDAB-SLNs based on the concentration and time of exposure, using different cell lines. In conclusion, the choice of the right surfactant for biological applications influences the biocompatibility of the nanoparticles. Regardless the type of drug delivery system, not only the cytotoxicity of the drug-loaded nanoparticles should be assessed, but also the blank (non-loaded) nanoparticles as their surface properties play a decisive role both in vitro and in vivo.

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ul Haq, Naveed, Muhammad Usman, Ajaz Hussain, Zahoor Hussain Farooqi, Muhammad Saeed, Sadia Hanif, Muhammad Irfan, Mohammad Siddiq, and Usman Ali Rana. "Partitioning of reactive yellow 86 between aqueous and micellar media studied by differential absorption spectroscopy." Canadian Journal of Chemistry 95, no. 6 (June 2017): 697–703. http://dx.doi.org/10.1139/cjc-2016-0442.

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The present study describes the partitioning of a reactive dye, reactive yellow 86, between aqueous and micellar media of a cationic surfactant (cetyltrimethyl ammonium bromide, CTAB), as well as an anionic surfactant (sodium dodecyl sulphate, SDS). In a systematic investigation, we have recorded the UV–vis absorption spectra of the dye as a function of surfactant’s concentration above and below the critical micelle concentration (CMC). Absorption spectra display a red shift in the case of CTAB and a hypochromic shift upon using SDS. The partition coefficient (Kx) was calculated using differential absorption data, and the value of free energy of partition (ΔGp) was calculated using this Kx value. The results revealed that the dye is solubilized in CTAB micelles to a greater extent than in SDS micelles.

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Ruhsing Pan, J., C. Huang, and C. Gang Fu. "Effect of surfactant on alum sludge conditioning and dewaterability." Water Science and Technology 41, no. 8 (April 1, 2000): 17–22. http://dx.doi.org/10.2166/wst.2000.0137.

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Sludge disposal has become a new challenge for the Taiwan government due to the increasing demand for better quality and greater quantity of water. In some water treatment plants, surfactant has been applied in the flotation process to improve its performance, which suggests the use of surfactant in sludge conditioning. In this study, effects of surfactants on the conditioning of the alum sludge collected from Feng-Yuan Water Treatment Plant were investigated. Surfactants of various charges, namely CTAB and SDS, were added to sludge samples in various amounts, and their effects on sludge dewaterability were evaluated. Surfactants were also added with either cationic or anionic polymers to better understand their effects on the mechanism of sludge conditioning and the feasibility as coagulant aid.Experimental results indicate that applying surfactants alone in sludge system decrease the filterability of sludge, but increase the sludge dewatering rate at optimum dosage. Cationic surfactant was proven possible as conditioning aid for the cationic polymer. The order of surfactant and polymer addition is the key to additive function. On the other hand, when the polymer of opposite charge was added with the surfactant, co-precipitation occurred which resulted in decreased filterability and dewaterability.

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Klimonda, A., and I. Kowalska. "Application of polymeric membranes for the purification of solutions containing cationic surfactants." Water Science and Technology 79, no. 7 (April 1, 2019): 1241–52. http://dx.doi.org/10.2166/wst.2019.115.

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Abstract The aim of the study was to examine physicochemical properties of three cationic surfactants and to evaluate the effectiveness of their removal with the use of polymeric membranes. The experiments were performed in a laboratory scale set-up with the use of Microdyn-Nadir® nanofiltration and ultrafiltration membranes. Cetrimonium bromide (CTAB), benzalkonium chloride (BAC) and Tequat LC90i (TEAQ) were chosen for the test. In the experiments, surfactant solutions in a wide range of concentration were treated (50–3,000 mg L−1). The experimental research included evaluation of the effect of membrane type and solution parameters (surfactant type and concentration, presence of inorganic compounds) on the process efficiency (retention coefficient and permeate flux). It was shown that surfactant removal by means of the pressure-driven membrane processes is an extensive issue and its efficiency depends on many factors. Ultrafiltration and nanofiltration membranes proved to be usable in CTAB removal (separation exceeded 90%); however, the process effectiveness was affected by surfactant concentration, membrane polymer type and membrane pore size. Separation obtained for BAC was on the lower level – the use of nanofiltration membranes brought maximum retention of 70%. TEAQ separation was very high and reached 100% with the use of ultrafiltration membranes. Mineral salt addition led to significant drop in surfactant retention.

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Baghdadi, Majid, Mahmoud Mazarji, Mohammad Sabouhi, Abbass Jafari Kang, and Aghdas Jafari. "Removal of Cationic Surfactants from Aqueous Solutions by Modified Cotton as a Novel High Capacity and Low Cost Adsorbent." JOURNAL OF ADVANCES IN CHEMISTRY 9, no. 3 (December 1, 2013): 2062–71. http://dx.doi.org/10.24297/jac.v9i3.1013.

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Direct and indirect releases of large quantities of surfactants to the environment may result in serious health and environmental problems. Therefore, surfactants should be removed from water before release to the environment or delivery for public use. Using cotton-based adsorbent may be an effective technique to remove surfactants. In this study, the removal of cationic surfactants by modified cotton was investigated. N-Cetyl-N,N,N-trimethylammonium bromide (CTAB) was selected as a cationic surfactant for the experiments. The results revealed that the modified cotton has a high affinity toward the cationic surfactants. Experiments were conducted to examine the effects of applied adsorbent dosage, initial concentration of adsorbate, pH, temperature, salt concentration on the removal efficiency. By increasing the salt concentration, removal efficiency was decreased slightly. The temperature had an adverse effect on removal efficiency. The adsorption of the CTAB increases with increasing pH of the solution. A series of batch experiments were performed to determine the sorption isotherms of modified cotton. Surfactant equilibrium data fitted very well to the Langmuir model. The Langmuir model showed that the maximum adsorption was 909 mg/g which is higher than the capacity of other adsorbents reported until now. The pseudo first-, second- order and corresponding rate equation kinetic models were investigated. Adsorption complies with a pseudo-second-order rate equation.

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Zulfajri, Muhammad, Wei-Jie Huang, Genin-Gary Huang, and Hui-Fen Chen. "Effects of Different Surfactant Charges on the Formation of Gold Nanoparticles by the LASiS Method." Materials 14, no. 11 (May 29, 2021): 2937. http://dx.doi.org/10.3390/ma14112937.

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The laser ablation synthesis in solution (LASiS) method has been widely utilized due to its significant prospects in laser microprocessing of nanomaterials. In this study, the LASiS method with the addition of different surfactant charges (cationic CTAB, nonionic TX-100, and anionic SDS) was used to produce Au NPs. An Nd:YAG laser system at 532 nm excitation with some synthetic parameters, including different laser fluences, ablation times, and surfactant concentrations was performed. The obtained Au NPs were characterized by UV-Vis spectroscopy, transmission electron microscopy, and zeta potential analyzer. The Au NPs exhibited the maximum absorption peak at around 520 nm for all samples. The color of Au NPs was changed from red to reddish by increasing the laser fluence. The surfactant charges also played different roles in the Au NPs’ growth during the synthesis process. The average sizes of Au NPs were found to be 8.5 nm, 5.5 nm, and 15.5 nm with the medium containing CTAB, TX-100, and SDS, respectively. Besides, the different surfactant charges induced different performances to protect Au NPs from agglomeration. Overall, the SDS and CTAB surfactants exhibited higher stability of the Au NPs compared to the Au NPs with TX-100 surfactant.

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Kaczerewska, Olga, Isabel Sousa, Roberto Martins, Joana Figueiredo, Susana Loureiro, and João Tedim. "Gemini Surfactant as a Template Agent for the Synthesis of More Eco-Friendly Silica Nanocapsules." Applied Sciences 10, no. 22 (November 15, 2020): 8085. http://dx.doi.org/10.3390/app10228085.

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Silica mesoporous nanocapsules are a class of “smart” engineered nanomaterials (ENMs) applied in several fields. Recent studies have highlighted that they can exert deleterious effects into marine organisms, attributed to the use of the toxic cationic surfactant N-hexadecyl-N,N,N-trimethylammonium bromide (CTAB) during the synthesis of ENMs. The present study reports the successful synthesis and characterization of novel gemini surfactant-based silica nanocapsules. The gemini surfactant 1,4-bis-[N-(1-dodecyl)-N,N-dimethylammoniummethyl]benzene dibromide (QSB2-12) was chosen as a more environmentally-friendly replacement of CTAB. Nanocapsules were characterized by scanning electron microscopy (SEM), Fourier-transformed infrared spectroscopy (FTIR), dynamic light scattering (DLS), thermogravimetric analysis (TGA) and N2 adsorption-desorption isotherms. Short-term exposure effects of new ENMs were evaluated in four marine species (Nannochloropsis gaditana, Tetraselmis chuii and Phaeodactylum tricornutum) and the microcrustacean (Artemia salina). The replacement of the commercial cationic surfactant by the gemini surfactant does not change the structure nor the environmental behaviour in seawater of the newly synthesised silica nanocontainers. Additionally, it is demonstrated that using gemini surfactants can reduce the toxicity of novel silica nanocapsules towards the tested marine species. As a result, environmentally-friendly ENMs can be obtained based on a safe-by-design approach, thereby fitting the concept of Green Chemistry.

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Doong, Ruey-an, Ya-Wen Wu, and Wen-gang Lei. "Surfactant enhanced remediation of cadmium contaminated soils." Water Science and Technology 37, no. 8 (April 1, 1998): 65–71. http://dx.doi.org/10.2166/wst.1998.0309.

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An investigation involving the addition of surfactant to remediate cadmium-contaminated soils was performed to determine the optimal surfactant enhanced remediation system. Anionic (sodium dodecyl sulfate, SDS), nonionic (Triton X-100, TX100) and cationic (cetyltrimethylammonium bromide, CTAB) surfactants were used to elucidate the extraction efficiency of surfactant. EDTA and diphenylthiocarbazone (DPC) were also added to enhance the extraction efficiencies of surfactants. Moreover, the pH effect was examined to determine the optimal surfactant systems. The addition of anionic and nonionic surfactants can enhance the desorption rates of cadmium, lead and zinc, whereas the addition of cationic surfactant decreased the desorption efficiency of heavy metals. The desorption efficiency was found to increase linearly with the increasing surfactant concentration below critical micelle concentration (CMC) and remained relatively constant above the CMC. Moreover, the addition of EDTA can significantly enhance the desorption efficiency of heavy metals. Cationic surfactant was shown to be a more effective surfactant than nonionic and anionic surfactants in extracting heavy metals under acidic environment. The desorption efficiency of heavy metal in the surfactant/EDTA mixture system was in the order of Cd > Pb > Zn. However, the addition of DPC lowered the heavy metal removals by 2 to 4 times. Also, increasing pH value can decrease the extraction capabilities of nonionic and anionic surfactants. The results of this study demonstrate that surfactant in combination with complexing agents can be effectively used as chemical amendments to flush cadmium-contaminated soil by proper selection of type and concentration of surfactant and complexing agent at different pH values.

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Tazhibayeva, Sagdat, Kuanyshbek Musabekov, Zhenis Kusainova, Ardak Sapieva, and Nurlan Musabekov. "Complex Formation of Polyacrylic Acid with Surfactants of Different Hydrophobicity." Applied Mechanics and Materials 752-753 (April 2015): 212–16. http://dx.doi.org/10.4028/www.scientific.net/amm.752-753.212.

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Complex formation processes of polyelectrolytes with surfactant ions are close model to protein - lipid interactions in living organisms. Furthermore, polymer – surfactant complexes are widely used as stabilizers of industrial dispersions and structurants of soil. When using the polymer-surfactant complexes the hydrophilic-lipophilic balance has the great importance. The interaction of polyacrylic acid with alkylammonium salts of different hydrophobicity: cetyltrimethylammonium bromide, dilaurildimethylammonium bromide and dioctadecyldimethylammonium chloride was studied by potentiometry, spectrophotometry, viscometry and electrophoresis methods. It was established that the complex formation of polyacrylic acid with cationic surfactants is carried out due to the electrostatic interaction between carboxyl groups of the polymer and cations of surfactants, which stabilized by hydrophobic interactions between their non-polar parts. The phenomenon of hysteresis in the change of the reduced viscosity of system surfactant /polyacrylic acid with temperature variation in the range of 20-60 °C was found. The possibility of using the complex formation process for water purification from CTAB has been shown. The degree of purification is 99.6-99.8%.

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Hosseinzadeh, Reza, and Mohammad Gheshlagi. "Interaction and micellar solubilization of diclofenac with cetyltrimethylammonium bromide: A spectrophotometric study." Collection of Czechoslovak Chemical Communications 74, no. 3 (2009): 503–13. http://dx.doi.org/10.1135/cccc2008021.

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In this study, the interaction of diclofenac (Dic) with cationic surfactant cetyltrimethylammonium bromide (CTAB) was investigated. The effect of cationic micelles on solubilization of diclofenac in aqueous micellar solution was studied at pH 6.8, 29 °C and various drug concentrations. The binding of diclofenac to CTAB micelles was accompanied by a batochromic shift in the drug absorption spectra. The solubility of diclofenac increased with increasing surfactant concentration as a consequence of the association between the drug and micelles. From the results, the binding constants Kb, was obtained. By using the pseudo-phase model, the partition coefficient between the bulk water and CTAB micelles, Kx, and the Gibbs energy of binding were calculated. The value of binding constant and partition coefficient are increased by increasing of diclofenac concentration.

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Tian, Maozhang, Fan Zhang, Lu Wang, Xing Dong, Lifei Zhang, and Xia Guo. "Activity of Polyphenoloxidase in red Fuji Apples Promoted with Cationic Surfactant – Role of Surfactant Structure." Tenside Surfactants Detergents 58, no. 5 (September 1, 2021): 383–93. http://dx.doi.org/10.1515/tsd-2020-2322.

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Abstract In this study, we observed the activity of polyphenoloxidase (PPO) in red Fuji apples in the presence of single-chained surfactants (including cetyl trimethyl ammonium bromide (CTAB), and dodecyl trimethyl ammonium bromide (DTAB)) and gemini surfactants (pentamethylene-α,ω-bis(dodecyl dimethyl ammonium bromide), octamethylene-α,ω-bis(dodecyl dimethyl ammonium bromide, dodecamethylene-α,ω-bis(dodecyl dimethyl ammonium bromide), pentamethylene-α,ω-bis(cetyl dimethyl ammonium bromide), and octamethylene-α,ω-bis(cetyl dimethyl ammonium bromide)). It was found that all these surfactants enhanced the activity of PPO in a wide range of temperature at low content. When PPO was denatured by incubating at high temperature, the surfactants caused reactivation of PPO. Compared to the single-chained surfactants, the gemini surfactants increased PPO activity at a much lower concentration. Moreover, the single-chained surfactant and the gemini surfactant acted together to further increase PPO activity, and the synergistic effect reduced the amount of surfactant used. In addition, the Michaelis-Menten constant for PPO did not change in the presence of the surfactants, suggesting the active site should remain well with the surfactants.

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Acharyya, Shankha S., Shilpi Ghosh, and Rajaram Bal. "Fabrication of three dimensional (3D) hierarchical Ag/WO3 flower-like catalyst materials for the selective oxidation of m-xylene to isophthalic acid." Chemical Communications 51, no. 27 (2015): 5998–6001. http://dx.doi.org/10.1039/c5cc00351b.

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Wang, Chunjie, Aihua Zhang, and Hamid Reza Karimi. "Effects of Surfactants on the Performance ofCeO2Humidity Sensor." Mathematical Problems in Engineering 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/723050.

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NanosizedCeO2powders were synthesized via hydrothermal method with different types of surfactants (polyethylene glycol (PEG), cetyltrimethylammonium bromide (CTAB), and sodium dodecylbenzenesulfonate (SDBS)). X-ray diffraction, Raman spectroscopy, and transmission electron microscopy were utilized to characterize the phase structures and morphologies of the products. The sample with CTAB as surfactant (CeO2-C) has the largest specific surface area and the smallest particle size among these three samples. The humidity sensor fabricated byCeO2-C shows higher performance than those usedCeO2-P andCeO2-S. The impedance of theCeO2-C sensor decreases by about five orders of magnitude with relative humidity (RH) changing from 15.7 to 95%. The response and recovery time are 7 and 7 s, respectively. These results indicate that the performance ofCeO2humidity sensors can be improved effectively by the addition of cationic surfactant.

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Dantoni, Patrícia, Ana Clara B. Rodrigues, Margareth Mie N. Matsuda, and Nina Coichev. "Effect of some surfactants on the chemiluminescent reactions of bis(2,4,6-trichlorophenyl)oxalate and bis(2-nitrophenyl)oxalate with hydrogen peroxide." Canadian Journal of Chemistry 90, no. 6 (June 2012): 534–41. http://dx.doi.org/10.1139/v2012-025.

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The chemiluminescent reactions of bis(2,4,6-trichlorophenyl)oxalate (TCPO) and bis(2-nitrophenyl)oxalate (2-NPO) with hydrogen peroxide in acetonitrile/water micellar systems (anionic, cationic, and non-ionic) and γ-cyclodextrin were studied in the presence of fluoranthene or 9,10-diphenylanthracene, imidazole, and two buffer solutions, HTRIS+/TRIS and H2PO4–/HPO42–. The relative chemiluminenscence (CL) intensity is higher in the presence of the cationic (DDAB, CTAC, DODAC, and OTAC), anionic (SDS), and non-ionic (Tween 80) surfactants. In the presence of some non-ionic surfactants (Brij 35, Brij 76, and Tween 20), the CL intensity was partially quenched compared with the reaction with no surfactant. The sensitivity for hydrogen peroxide determination in the range 0.01 × 10−4 to 1.0 × 10−4 mol L–1, considering the slope of the calibration curves (maximum peak height of CL vs. concentration), improved with the introduction of DDAH, CTAB, and SDS in HTRIS+/TRIS buffer.

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Andrew Lin, Kun-Yi, Hongta Yang, and Wei-Der Lee. "Enhanced removal of diclofenac from water using a zeolitic imidazole framework functionalized with cetyltrimethylammonium bromide (CTAB)." RSC Advances 5, no. 99 (2015): 81330–40. http://dx.doi.org/10.1039/c5ra08189k.

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Noirjean, Cecile, Fabienne Testard, Christophe Dejugnat, Jacques Jestin, and David Carriere. "Molten fatty acid based microemulsions." Physical Chemistry Chemical Physics 18, no. 23 (2016): 15911–18. http://dx.doi.org/10.1039/c6cp00533k.

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We show that ternary mixtures of water (polar phase), myristic acid (MA, apolar phase) and cetyltrimethylammonium bromide (CTAB, cationic surfactant) studied above the melting point of myristic acid allow the preparation of microemulsions without adding a salt or a co-surfactant.

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Seyfoori, Amir, Hamideh Mahmoodzadeh Hosseini, Abbas Ali Imani Fooladi, and Mohammad Reza Nourani. "Synthesize and Characterization of Hollow Hydroxyapatite Nanopowders with Different Morphologies: Role of Cationic and Non-Ionic Surfactants." Advanced Materials Research 829 (November 2013): 268–73. http://dx.doi.org/10.4028/www.scientific.net/amr.829.268.

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Today, hydroxyapatite hollow nanopowders have attracted the attention of researchers as a reliable option for drug and protein delivery systems. In this study, nanohydroxyapatite powders with different morphologies were successfully synthesized via wet chemical precipitation method. Elongated rice-shape and semi-spherical nanopowders with hollow structures were synthesized using CTAB and the mixture of cetyltrimethylammonium bromide (CTAB) and polyethylene glycol (PEG) as surfactants respectively. The properties of these nanopowders were charecterized by means of scanning electron microscopy, x-ray diffraction, fourier transform infrared spectroscopy and nitrogen adsorption experiments. The results showed that using CTAB as a surfactant not only can alter the morphology of the HAp nanopowders but also it can have a significant effect on the structure of them, so that by using CTAB and mixture of CTAB and PEG, nanoporous HAp nanopowders were acquired. Moreover, the analysis of nitrogen adsorption showed a higher average surface area for CTAB synthesized HAp in comparison to CTAB/PEG synthesized nanopowder. The amount of live cells adjacent to the HAp suspensions in PBS (50, 100, 200 mg/L) was evaluated by MTT experiment. The results of MTT assay showed the ascending cell proliferation trend for spherical nanopowders by an increment in suspension concentration, while this trend was descending for rice-shape nanopwders.

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Vadivel, M., R. Ramesh Babu, K. Ramamurthi, and M. Arivanandhan. "CTAB cationic surfactant assisted synthesis of CoFe2O4 magnetic nanoparticles." Ceramics International 42, no. 16 (December 2016): 19320–28. http://dx.doi.org/10.1016/j.ceramint.2016.09.101.

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Zueva, O. S., Y. K. Mongush, and A. O. Makarova. "Carbon Nanotubes Microenvironment in Ionic Surfactant Water Solutions." Solid State Phenomena 284 (October 2018): 713–18. http://dx.doi.org/10.4028/www.scientific.net/ssp.284.713.

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The processes of aggregation of anionic (SDS) and cationic (CTAB) molecules into supramolecular formations and the effect of carbon nanotubes on the processes were investigated by conductometry and tensiometry methods. Concentration dependences of the specific electrical conductivity and surface tension of aqueous SDS and CTAB dispersions and suspensions of carbon nanotubes of the carbon nanomaterial Taunit in these dispersions were obtained. A conclusion on the change in the conformation of CTAB micelles in the presence of carbon nanotubes was drawn. A significant increase in the packing density of CTAB molecules and their ordering in the monomolecular layer at the water-air interface in the presence of carbon nanotubes was shown. In particular, this makes it possible to control the properties of the surfactant surface layer by means of carbon nanotubes.

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Shokuhfar, Ali, S. Alibeigi, Mohammad Reza Vaezi, and Sayed Khatiboleslam Sadrnezhaad. "Synthesis of Fe₃O₄ Nanoparticles Prepared by Various Surfactants and Studying their Characterizations." Defect and Diffusion Forum 273-276 (February 2008): 22–27. http://dx.doi.org/10.4028/www.scientific.net/ddf.273-276.22.

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Magnetite (Fe3O4) nanoparticles were prepared simply by the reverse co-precipitation method from the solution of ferrous/ferric mixed salt in the presence of cationic surfactant (cetyl trimethyl ammonium bromide, CTAB) and nonionic surfactant (Polyethylene glycol, PEG) in two concentrations. Meanwhile, Fe3O4 nanoparticles without surfactant are also synthesized under the same condition for comparison. In addition via the reverse co-precipitation method, the pH which is an important factor in synthesis of magnetite was controlled at high values easily. The experimental results reveal that addition of surfactants affected on the size and morphology of the nanoparticles based on the X-ray diffraction (XRD) and scanning electron microscope (SEM) characterizations.

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Liu, Da Yong, and Jie Yu. "The Influence of CTAB Surfactant on the Dispersion of Al₂O₃ Particles and Deposition Rate of Electroless Ni-P-Al₂O₃ Coatings." Advanced Materials Research 1095 (March 2015): 641–46. http://dx.doi.org/10.4028/www.scientific.net/amr.1095.641.

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In this paper, electroless Ni-P-Al2O3coatings have been synthesized on mild steel shaft by adding various concentration of cetyltrimethyle ammonium bromide (CTAB) into plating baths. Compared with Polyvinyl pyrrolidone (PVPk30), cationic surfactant CTAB shows better effect in dispersing the Al2O3particles. With the increasing of CTAB concentration in the plating baths, dispersion of Al2O3particles in the Ni-P-Al2O3coatings was improved due to high electrostatic repulsive force between Al2O3particles and CTAB molecular, whereas deposition rate of the Ni-P-Al2O3coatings was decreased.

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Abdi, Mahnaz M., Nur Farhana Waheeda Mohd Azli, Hong Ngee Lim, Paridah Md Tahir, Gholamreza Karimi, Yeoh Beng Hoong, and Mohammad Khorram. "Polypyrrole/tannin biobased nanocomposite with enhanced electrochemical and physical properties." RSC Advances 8, no. 6 (2018): 2978–85. http://dx.doi.org/10.1039/c7ra13378b.

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Tannin (TA) extracted from Acacia mangium and a cationic surfactant, cetyltrimethylammonium bromide (CTAB), were used to modify and enhance the physical and electrochemical properties of polypyrrole (PPy) composite.

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Chen, Kan Lin, Chien Jung Huang, Pin Hsiang Chiu, and Yeong Her Wang. "Synthesis of the Gold Nanocubes by Electrochemical Method with Surfactant Solution and Acetone Solvent Addition." Key Engineering Materials 434-435 (March 2010): 434–37. http://dx.doi.org/10.4028/www.scientific.net/kem.434-435.434.

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Monodispersed gold nanocubes of highly uniform size were fabricated by a simple electrochemical method. The lengths of the edges of the gold nanocubes were about 30 nm. The growth solution was prepared from two cationic surfactant solutions as micelle templates with added acetone solvent. The primary surfactant was hexadecyltrimethylammonium bromide (CTAB) and the co-surfactant was tetradodecylammonium bromide (TTAB).

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Li, Yin Ming, and Fu Shen Zhang. "Characterization of a Sorbent Derived from Construction and Demolition Waste." Advanced Materials Research 878 (January 2014): 199–205. http://dx.doi.org/10.4028/www.scientific.net/amr.878.199.

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Construction and demolition waste (C&D) was employed as a raw material to synthesize sorbent by fusion-hydrothermal process in order to effectively use this type of waste material. The specific surface area and the cation exchange capacity (CEC) values of the sorbent were 308.2 m2 g-1 and 625.6 mmol/100 g-1, respectively. It was found that the sorbent was quite effective for ammonium ion due to the high CEC value. The sorbent possessed high PFOS sorption capacities after load with cationic surfactant (Cetyltrimethyl Ammonium Bromide, CTAB), the sorption capacities of CTAB-modified sorbents enhanced with the increase of CTAB loading amount. This study provides an effective way for the C&D waste utilization.

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Mohamed, Dalia Emam, Nabel A. Negm, and Marwa R. Mishrif. "Micellization and Interfacial Interaction Behaviors of Gemini Cationic Surfactants–CTAB Mixed Surfactant Systems." Journal of Surfactants and Detergents 16, no. 5 (April 19, 2013): 723–31. http://dx.doi.org/10.1007/s11743-013-1477-x.

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Stoichev, Teodor, Paulo de Morais, M. Clara P. Basto, and M. Teresa S. D. Vasconcelos. "Interferences of Surfactants During Determination of Chlorophenols by Acetylation Coupled to Headspace-Solid Phase Microextraction-Gas Chromatography with an Electron Capture Detector." Journal of AOAC INTERNATIONAL 98, no. 2 (March 1, 2015): 524–28. http://dx.doi.org/10.5740/jaoacint.14-126.

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Abstract The micellar extraction (ME) of chlorophenols (CPs) from solid samples is rapid and avoids the use of organic solvents. The cationic surfactant cetyltrimethylammonium bromide (CTAB) is a powerful agent for ME of CPs. However, CTAB will be an important interference when the extracts are subsequently analyzed by direct solid phase microextraction (SPME) without a previous derivatization step. Therefore, CTAB is usually replaced by the nonionic surfactant polyoxyethylene-10-lauryl ether (POLE), which causes less interference but is less efficient in extracting CPs. In order to assess to what extent the derivatization of CPs with headspace (HS) sampling would be able to reduce surfactant interferences, CPs were measured in the presence of CTAB or POLE using acetylation and HS-SPME coupled to GC with an electron capture detector. Experiments were carried out both in water and in a 0.1 g/mL solution of NaCl (salting out agent). Acetylation and HS-SPME strongly decreased the interference of CTAB for CP determination. Therefore, the application of CTAB followed by SPME determination for an efficient ME of CPs from solid samples should be reconsidered since using CTAB with HS-SPME after acetylation proved to be a potential tool for CP determination in those matrixes after method optimization.

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Zhou, Mingsong, Wenli Wang, Dongjie Yang, and Xueqing Qiu. "Preparation of a new lignin-based anionic/cationic surfactant and its solution behaviour." RSC Advances 5, no. 4 (2015): 2441–48. http://dx.doi.org/10.1039/c4ra10524a.

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Rashid, Sadaf, Muhammad Usman, Tanvir Shahzad, Muhammad Saeed, Atta Ul Haq, Muhammad Ibrahim, Muhammad Siddiq, and Misbah Iram. "The Differential Spectroscopic Investigation of Partitioning of Reactive Dyes in Micellar Media of Cationic Surfactant, Cetyl Trimethylammonium Bromide (CTAB)." Zeitschrift für Physikalische Chemie 233, no. 2 (February 25, 2019): 183–99. http://dx.doi.org/10.1515/zpch-2018-1142.

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Abstract This manuscript reports the solubilization of two reactive dyes viz. reactive black-5 (RB-5) and reactive black-8 (RB-8) in the micellar media of cationic surfactant, cetyl trimethylammonium bromide (CTAB) by differential UV/visible spectroscopy. Absorption spectra of said dyes in the presence of CTAB provide strong evidence about dye–surfactant interaction. In premicellar region ion association pair is formed between dye and surfactant while in post micellar region dye molecules get accommodated within the micelles. The values of critical micelle concentration (CMC) of CTAB in the presence of dyes, partition coefficient; Kx, free energy of partition, ∆Gp, binding constant, Kb and free energy of binding, ∆Gb were determined and compared for both dyes. It is, thus, concluded that RB-5 is solubilized to greater extent than RB-8 because of its incorporation in palisade layer of micelle close to micelle-water interface.

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Ismail, Raid A., Hanan A. Rawdhan, and Duha S. Ahmed. "High-responsivity hybrid α-Ag2S/Si photodetector prepared by pulsed laser ablation in liquid." Beilstein Journal of Nanotechnology 11 (October 21, 2020): 1596–607. http://dx.doi.org/10.3762/bjnano.11.142.

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We report the synthesis of α-Ag2S nanoparticles (NPs) by one-step laser ablation of a silver target in aqueous solution of thiourea (Tu, CH4N2S) mixed with cationic cetyltrimethylammonium bromide (CTAB) as surfactant. The effect of the CTAB surfactant on the structural, morphological, optical, and elemental composition of Ag2S NPs was evaluated using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and UV–vis spectroscopy. The optical absorption decreased and the optical energy gap of α-Ag2S increased from 1.5 to 2 eV after the CTAB surfactant was added to the Tu solution. XRD studies revealed that the synthesized Ag2S NPs were polycrystalline with a monoclinic structure and that crystallinity of the nanoparticles was improved after adding CTAB. Raman studies revealed the presence of peaks related to Ag–S bonds (Ag modes) and the longitudinal optical phonon 2LO mode. Scanning electron microscopy investigations confirmed the production of monodisperse Ag2S NPs when using the CTAB surfactant. The optoelectronic properties of α-Ag2S/p-Si photodetector, such as current–voltage characteristics and responsivity in the dark and under illumination, were also improved after using the CTAB surfactant. The responsivity of the photodetector increases from 0.64 to 1.85 A/W at 510 nm after adding CTAB. The energy band diagram of the α-Ag2S/p-Si photodetector under illumination was constructed. The fabricated photodetectors exhibited reasonable stability after three weeks of storage under ambient conditions with a responsivity of 70% of the initial value.

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Le Thi, Dung, Loan Nguyen Quynh, Thang Nguyen Duc, Son Le Thanh, and Duc Pham Tien. "Adsorption characteristics of 2,4-dichorophenoxy acetic acid onto surfactant modified titania nanoparticles." Vietnam Journal of Catalysis and Adsorption 10, no. 4 (August 23, 2021): xx. http://dx.doi.org/10.51316/jca.2021.061.

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The present study investigated adsorption of 2,4-dichorophenoxy acetic acid(2,4-D) on titania (TiO2) nanoparticles with surface modification by cationic surfactant, cetyltrimethylammonium bromide (CTAB). Titania nanoparticles which were successfully synthesized by sol-gel method, were characterized by X-ray diffraction (XRD) and Transmission electron microscopy (TEM). Surface modification of TiO2 with CTAB enhanced the removal of 2,4-D significantly. Some effective conditions affect to the removal of 2,4-D using CTAB modified TiO2 such as pH and adsorbent dosage were systematically studied and found to be 5 and 10 mg/mL, respectively. Adsorption mechanisms of 2,4-D onto CTAB modified TiO2 was suggested based on the change in surface charge after adsorption.

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Temerk, Yassien, Hossieny Ibrahim, and Nasser Farhan. "Square wave adsorptive stripping voltammetric determination of anticancer drug nilutamide in biological fluids using cationic surfactant cetyltrimethylammonium bromide." Analytical Methods 7, no. 21 (2015): 9137–44. http://dx.doi.org/10.1039/c5ay01811k.

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Abstract:

A sensitive square wave adsorptive stripping voltammetric method was described for the determination of anticancer drug nilutamide in human biological fluids based on the enhancement effect of the cationic surfactant: cetyltrimethylammonium bromide (CTAB).

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Zhu, Jia Ming, Zhong Min Wang, Song Tao, and Ying Peng. "Effect of Surfactants on Morphology and Luminescent Properties of YAG:Ce Phosphors." Materials Science Forum 815 (March 2015): 313–17. http://dx.doi.org/10.4028/www.scientific.net/msf.815.313.

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Abstract:

Using anionic surfactant sodium dodecylsulfate (SDS), cationic surfactant cetyltrimethylammonium bromide (CTAB) and nonionic surfactant polyethylene glycol 20000 (PEG20000) and glyceryl monostearate (monostearin) respectively, Ce-doped Y3Al5O12(YAG:Ce3+(6%)) yellow phosphors were prepared by a combination method of high energy ball milling and solid state reaction. The effects of surfactant type on structure, morphology and luminescence properties were investigated by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and fluorescence spectrometer. The results showed that the crystal structure of YAG:Ce3+phosphors were not changed with the introduction of surfactants,but their morphology was greatly influenced. The maximum PL intensity was obtained for the nonionic surfactant PEG20000 due to the more uniform morphology and size as well as more homogeneous distribution of particles. Also, the results demonstrated that surfactant concentration had a vital effect on morphology and fluorescent properties of the phosphors,and the optimum amount of surfactant is 10 wt%.

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Journal articles on the topic 'Cationic surfactant CTAB'

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