Presence Of TX-100 Research Articles

Novel insights into the photochemical transformation of neonicotinoid insecticides: Potential involvement of adjuvants

Commercial pesticide formulations often contain both the active ingredient and different adjuvants, the potential impacts of adjuvants on pesticides’ transformation have been barely considered. In this study, effects of typical adjuvants (i.e. hexadecyl trimethyl ammonium bromide (CTAB), hexadecyl trimethyl ammonium chloride (CTAC) and p-Octyl polyethylene glycol phenyl ether (TX-100)) on the photodegradation of four selected neonicotinoid insecticides (NIs), including thiamethoxam (TMX), dinotefuran (DIN), imidacloprid (IMP) and acetamiprid (ACP) were systematically investigated. Specifically, CTAB and CTAC exhibited minimal or no impact on the photolysis of four NIs, while TX-100 significantly inhibited their decay. Such inhibitory effect could mainly be attributed weakening the formation of key transient intermediates, such as the corresponding radical cation (NI•+), radical anion (NI•-) as well as hydrated electron (eaq-). Photoproducts identification revealed a novel transformation pathway of NIs in the presence of TX-100, characterized by de-chain reactions, resulting in the formation of photostable dimeric photoproducts. These dimers exhibited varying toxicity: for TMX, DIN and IMP, their corresponding dimers showed increased toxicity compared to their parent compounds, whereas for ACP, they displayed decreased toxicity. These provide important information for the evaluation the environmental fates and toxicology of formulaic NIs.

Investigation on the stability of mixed AlOOH/SiO2 aqueous dispersions and their application to stabilize Pickering emulsions in the presence of TX-100 and enhance oil recovery

Both negatively charged SiO2 nanoparticle and positively charged AlOOH nanoparticle have been widely used in various fields, including enhanced oil recovery (EOR). In this study, the mixed binary AlOOH/SiO2 nanoparticle (MBN) systems are constructed and firstly employed in EOR. The measurements of zeta potential and Z-average diameter indicate that the stable MBN aqueous dispersion could be obtained by controlling AlOOH/SiO2 mass ratios, which is quantificationally confirmed via the e-DLVO theory. Then the ternary TX-100-AlOOH-SiO2 (TX-A-S) system exhibits the great ability to stabilize the emulsion at the much low nanoparticle concentration (0.15 wt% in total). The emulsion stability is further evaluated in the harsh conditions (high shear, temperature and electrolyte concentration). Moreover, core flooding and microscopic visualization experiments reflect the TX-A-S stabilized emulsion can dramatically enhance tertiary oil recovery (~23% of initial oil in place), which should be attributed to the high improvement of both displacement and sweep efficiency.

The effect of nanosilica sizes in the presence of nonionic TX100 surfactant on CO2 foam flooding

The aim of this research is to study the effect of hydrophilic silica nanoparticles, sizes as CO2 foam stabilizer in the presence of nonionic TX100 surfactant. Two nanosilica sizes, 15 and 70 nm, have been examined thoroughly. Physisorption of TX100 on silica nanoparticles (nanosilica) was characterized by adsorption isotherm and surface tension measurement, while CO2 foams stability was quantified based on their foamability, foam stability, particle partitioning in the foams, and bubble sizes. Results show that direct contact of TX100 with nanosilica does altered the wettability of hydrophilic nanosilica surface, enable them to lengthen CO2 foams life at certain surfactant and nanoparticles concentrations. For 15 nm nanosilica, CO2 foam stability shows excellent performance at 0.1 and 0.5 wt% TX100 concentrations. As for 70 nm nanosilica, CO2 foam demonstrates longer lifetime at much lower TX100 concentration, 0.01 wt%. Without the presence of TX100, CO2 foams exhibit undesirable lifetime performances for both nanosilica sizes. Nanosilica partitioning in CO2 foams structures demonstrate consistent relation with contact angle measurement. Estimated bubble sizes shows insignificant effect on CO2 foams life. With the assists of nanosilica and TX100, enhanced oil recovery via CO2 foam injection succeeds in increasing oil production by 13–22% of original oil-in-place (OOIP).

Group 14 Metallafluorenes as Sensitive Luminescent Probes of Surfactants in Aqueous Solution.

Sila- and germafluorenes containing alkynyl(aryl) substituents at the 2,7- position are strongly emissive with high quantum yields in organic solvents. Provided they are sufficiently soluble in water, their hydrophobic structures have the potential for many biological and industrial applications in the detection and characterization of lipophilic structures. To that end, the emission behaviors of previously synthesized 2,7- bis[alkynyl(biphenyl)]-9,9-diphenylsilafluorene (1), 2,7- bis[alkynyl(methoxynaphthyl)]-9,9-diphenylgermafluorene (2), 2,7- bis[alkynyl(p-tolyl)]-9,9-diphenylsilafluorene (3), and 2,7- bis[alkynyl(m-fluorophenyl)]-9,9-diphenylsilafluorene (4) were characterized in aqueous solution and in the presence of various surfactants. Despite a high degree of hydrophobicity, all of these metallafluorenes (MFs) are soluble in aqueous solution at low micromolar concentrations and luminesce in a common aqueous buffer. Further, the 2,7 substituent makes the emission behavior tunable (up to 30 nm). Fold emission enhancements in the presence of various surfactants are highest toward Triton X-100 and CTAB (ranging from 5 to 25 fold) and are lowest for the anionic surfactants SDS and SDBS. These enhancements are competitive with existing probes of surfactants. Quantum yields in buffer range from 0.11 to 0.34, competitive with many common fluorophores in biological use. Strikingly, MF quantum yields in the presence of TX-100 and CTAB approach 100 % quantum efficiency. MF anisotropies are dramatically increased only in the presence of TX-100, CTAB, and CHAPS. Coupled with the above data, this suggests that MFs associate with neutral and charged surfactant aggregates. Interactions with the anionic surfactants are weaker and/or leave MFs solvent exposed. These properties make metallafluorenes competitive probes for surfactants and their properties and behaviors, and thus could also have important biological applications.

The effect of Triton X surfactants on Pb (II) transport rate using bulk liquid membrane systems

Implementation of the "bulk liquid membrane" (BLM) system was investigated in terms of its efficiency for selective removal of heavy metal ions from natural resources and industrial wastewater. In this paper, the removal of lead (II) ions through a liquid membrane system and factors that influence the process were examined. The research was performed using the homemade transport cell. Two organic solvents were used as liquid membranes: 1,2-dichloroethane and chloroform. Metal ion concentration in aqueous phases was monitored by flame atomic absorption spectrophotometry, after 4 hours of experiment. Macrocyclic ether (dicyclohexano-18-crown-6) was used as ligand for Pb (II) ions. The effects of nonionic surfactants (Triton X-100, Triton X-45 and Triton X-405) added in the receiving phase of BLM system were investigated. The results showed significant increase in transport rate compared to systems without surfactants. Considering the surfactant structure, transport rate of Pb (II) ions followed the order: TX-100 >TX-45>TX-405. Presence of TX-100 increased transport of Pb (II) ions up to 78% through chloroform and 58% through 1,2-dichloroethane. Â

Optimization of semiconductor–electrolyte interfacial phenomena for stable and efficient photoelectrochemical water oxidation behavior of Bi2Mo2O9–Bi2MoO6 heterojunction

Bismuth molybdates are considered the essential photocatalysts due to their mesoporous structure, low energy gap, suitable ion conductions, acousto-optics, photo-conduction, and sensing properties. The present report describes a cost-effective route for developing stable and efficient photocatalysts for optical to chemical energy conversion and environmental purification. In this work, we have developed nano-structured mixed bismuth molybdates with different thicknesses in the presence of TX-100 as the surfactant through drop-cast route taking bismuth nitrate and ammonium molybdate as the precursors. Final products were subsequently dried and annealed in air at 600 °C for 3 h. The semiconductors’ photoelectrochemical performance was measured under periodic illumination in the presence of Na2SO4 (0.1 M) solution and (0.1 M) Na2SO3 with 0.1 M Na2SO4 for water and sacrificial oxidation, respectively. These materials exhibit noticeable photocatalytic activity even after successive runs, indicating stable behavior. The materials are composed of Bi2Mo2O9–Bi2MoO6 heterostructures and the film with optimized thickness yields a photocurrent of 220 µA/cm2 at 1.3 V. This value is exceptionally higher in magnitude than the literature reports employing conventionally prepared bismuth molybdates (1.8 µA/cm2). Electrochemical impedance and photocurrent action spectra support a noticeable photon to current conversion efficiencies of the materials under illumination.

Improving biodegradation of Bisphenol A by immobilization and inducer

Loss in activity remains key challenges for the potential use of laccase in industrial and environmental biotechnology. Enzyme immobilization is an exciting alternative for improving the stability and reusability of enzymatic processes. In this study, the laccase enzyme was successfully immobilized onto SiO2 supports through covalent binding. The stability and durability during the reuse of immobilized laccase were superior to free laccase. After 30 reaction cycles of continuous use, the relative activity was above 80%. In addition, immobilized laccase was able to degrade Bisphenol A (BPA) more effectively than free laccase, especially in the presence of TX-100. The BPA was completely degraded within an incubation time of 5h. The results suggest that immobilization is feasible for improving the stability and reusability of laccase for many applications.

Degradation of Triton X-100 surfactant/lipid regulator systems by ionizing radiation in water

The radiolytic degradation of Triton X-100 surfactant was investigated at concentrations below and above the critical micelle concentration (CMC, ~ 0.23 mmol dm−3) in air saturated aqueous solutions. At low concentrations the degradation took place both on the aromatic head and on the polyethoxylates chain, while above CMC it was shifted towards the chain. The CMC was higher in irradiated solutions at 10 Gy by a factor of 2, at 20 kGy by a factor of 3 than in the un-irradiated solution. The degradation of clofibric acid in the presence of TX-100 was more effective outside the micelles than inside them.

Surfactant-assisted enhancement of bioremediation rate for hexavalent chromium by water extract of Sajina (Moringa oleifera) flower

The presence of hexavalent chromium in waste water is a serious environmental problem due to its toxicity and carcinogenicity. Bioremediation is an efficient alternative to the conventional chemical methods of treatment. Bioremediation of toxic hexavalent chromium is done by the reduction of hexavalent chromium to relatively less toxic trivalent chromium. In this study, water extract of Sajina flower, which contains different types of reducing components such as sugar, amino acid, is used as reductant and the rate of bioremediation is increased by treatment with anionic and neutral surfactants. Here surfactants are used as catalyst in the bioremediation process. Sodiumdodecyl sulfate (SDS) is found to be the best catalyst. In the absence of surfactants, 60.37% of the total chromium(VI) is reduced within 285 h, whereas the removal percentage increases up to 96.25 and 99.37% in the presence of TX-100 and SDS, respectively, in minimum time.

Kinetics of the Degradation of l-Cysteine at Freshly Prepared Nano-sized MnO2 Surfaces in the Absence and Presence of TX-100

Nano-sized colloidal manganese dioxide was synthesized at room temperature by a chemical method in neutral medium without a stabilizing agent. The obtained MnO2 nano-sized colloid was found to be stable for several months and was characterized by means of UV–Vis spectroscopy, energy-dispersive X-ray spectrometer (EDX) and transmission electron microscopy. The EDX analysis confirmed the presence of Mn and O in the sample. The paper reports on the use of nano-sized colloidal manganese dioxide as an oxidant in the oxidation of cysteine (Cyst) in the absence and presence of surfactant (TX-100) at 35 °C. The study was carried out as functions of [MnO2], [Cyst], [HClO4] and temperature. The results show that the reaction proceeds through fast adsorption of Cyst onto the surface of the colloidal MnO2. Pseudo-first-order rate constants were found to increase with the increase in [TX-100]. This paper reports values of the reaction rates and activation parameters in the absence and presence of surfactant and proposes a plausible mechanism.

Behavior of aqueous stable colloidal nano-C60 aggregates exposed to TX100 micelles under different environmental conditions

C60, as one of carbon nanomaterials widely used in various fields, could be released into the water environment thus exerting some potential health risks to human beings. This work examined the behavior of aqueous stable colloidal nano-C60 (nC60) aggregates under different environmental conditions including Polyethylene glycol octylphenol ether (TX100) micelles concentration, pH, and reaction time when exposed to TX100 micelles. Results show that the nC60 aggregates became more dispersive and restored the capability of generating the singlet oxygen when exposed to TX100 micelles. With the increase of TX100 concentration, smaller average size of nC60 aggregates was observed in dynamic light scattering (DLS) analysis, the fluorescence intensity of TX100 was more quenched by nC60 aggregates, and the kinetic rate constant of generating the singlet oxygen for nC60 aggregates was improved. The mean size of nC60 aggregates in the presence of TX100 had no obvious variations when the pH ranged from 4 to 8. The longer reaction time between nC60 aggregates and TX100 led to a higher kinetic rate constant of generating the singlet oxygen. Collective data suggest that variations in physicochemical properties of nC60 aggregates are strongly dependent on the surrounding media under different environmental conditions and directly govern nC60’s transport behavior and potential toxicity.

Kinetics of Methyl Green Fading in the Presence of TX-100, DTAB and SDS

The rate constant of alkaline fading of methyl green (ME 2+ ) was measured in the presence of non ionic (TX100), cationic (DTAB) and anionic (SDS) surfactants. ME 2+ hydrolyses and fades in neutral water and in this work we search the effects of surfactants on its fading rate. The rate of reaction showed remarkable dependence on the electrical charge of the used surfactants. It was observed that the reaction rate constant decreased in the presence of DTAB and SDS and increased in the presence of TX-100. Binding constants of ME 2+ to TX-100, DTAB and SDS and the related thermodynamic parameters were obtained by classical (or stoichiometric) model. The results show that binding of ME 2+ to TX-100 and DTAB are two-region and that of SDS is threeregion. Also, the binding constants of ME 2+ to surfactant molecules in DTAB/TX-100 and SDS/TX-100 mixed

Influence of surfactants on the adsorption and elektrokinetic properties of the system: guar gum/manganese dioxide

The adsorption of non-ionic polysaccharide—guar gum (GG) in the presence or absence of the surfactants: anionic SDS, cationic CTAB, nonionic TX-100 and their equimolar mixtures SDS/TX-100, CTAB/TX-100 from the electrolyte solutions (NaCl, CaCl2) on the manganese dioxide surface (MnO2) was studied. The increase of GG adsorption amount in the presence of surfactants was observed in every measured system. This increase results from formation of complexes between the GG and the surfactant molecules. This observation was confirmed by the determination of the influence of GG on surfactants adsorption on the MnO2 surface. The increase of GG adsorption on MnO2 was the largest in the presence of the surfactant mixtures (CTAB/TX-100; SDS/TX-100) which is the evidence of the synergetic effect. The smallest amounts of adsorption were obtained in the presence of TX-100, which results from non-ionic character of this surface active agent. In the case of single surfactant solution CTAB has the best efficiency in increasing the amount of GG adsorption on MnO2 which results from strong interactions with GG and also with the negatively charged surface of the adsorbent. In order to determine the electrokinetic properties of the system, the surface charge density of MnO2 and the zeta potential measurements were performed in the presence of the GG macromolecules and the above mentioned surfactants and their mixtures. The obtained data showed that the adsorption of GG or GG/surfactants complexes on the manganese dioxide surface strongly influences the diffused part of the electrical double layer (EDL)—MnO2/electrolyte solution, but has no influence on the compact part of the electric double layer. This is the evidence that the polymers chains are directly bonded with the surface of the solid and the surfactants molecules are present in the upper part of the EDL.

Kinetics of Oxidation of dl-Tartaric Acid by Potassium Permanganate in Aqueuos and Aqueous Micellar Media

The kinetics of oxidation of dl-tartaric acid (TA) by potassium permanganate in acetic acid medium in the presence and absence of TX-100 (non-ionic surfactant) was investigated. At early stages, the reaction was found to be first order with respect to both permanganate and TA. The presence of TX-100 was found to catalyse the reaction and this effect was interpreted successfully in terms of pseudo-phase model. Activation parameters of the reaction in the presence/absence of TX-100 were obtained. A suitable mechanism, which agreed with the experimental findings was suggested.

Thermodynamic studies on mixed micellization of amphiphilic drug amitriptyline hydrochloride and nonionic surfactant Triton X-100

In the present work, we report the surface properties and mixed micellization of a tricyclic antidepressant drug amitriptyline hydrochloride (AMT) with nonionic surfactant poly(ethylene glycol) t-octylphenyl ether (TX-100) using surface tension measurements. The surface properties in aqueous solution of AMT drug in the absence and presence of TX-100 are presented. The critical micelle concentration (cmc), maximum surface excess concentration at the air/water interface (Γmax) and the minimum area per surfactant molecule at the air/water interface (Amin) parameters are evaluated. Γmax increases and cmc as well as Amin decrease with increasing concentration (mole fraction) of the additive (TX-100). We also report the thermodynamics of AMT in the absence and presence of TX-100 and evaluated Gibbs energies (viz., at air/water interface (Gmin(s)), the standard Gibbs energy change of micellization (ΔmicG0), the standard Gibbs energy change of adsorption (ΔadsG0), the excess free energy change of micellization (ΔGexm)).

Influence of anionic, cationic and nonionic surfactants on adsorption and desorption of oxytetracycline by ultrasonically treated and non-treated multiwalled carbon nanotubes

High adsorption capacity of carbon nanotubes (CNTs) may greatly determine the bioavailability and mobility of organic contaminants. The fate of contaminants adsorbed by CNTs may be substantially influenced by surfactants used both in the synthesis and dispersion of CNTs. The aim of this research was to determine the influence of surfactants (nonionic – TX100, cationic – CTAB and anionic – SDBS) on adsorption and desorption of oxytetracycline (OTC) by multiwalled carbon nanotubes (MWCNTs). The surfactants used had a substantial influence on both adsorption and desorption of OTC. The direction of changes depended clearly on the type of surfactant. In case of anionic SDBS, increased adsorption of OTC by MWCNTs was observed. The presence of TX100 and CTAB decreased the adsorption of OTC by MWCNTs significantly. The increase of OTC adsorption after ultrasonic treatment was observed in case of MWCNTs alone and MWCNTs with SDBS and TX100. However, ultrasonic treatment caused OTC adsorption decrease in the presence of CTAB. The change of pH had also an important effect on OTC adsorption in the presence of surfactants. Depending on the surfactant and pH, an increase or decrease of OTC adsorption was observed. The presence of surfactants increased OTC desorption from MWCNTs significantly as follows: SDBS = CTAB < TX100. The results obtained suggest new potential threats and constitute a basis for further research considering the bioavailability and toxicity of antibiotics in the presence of MWCNTs and surfactants.

Triton X −100 and TM Helices Increase Ordered Domain (lipid Raft) Size

It has been postulated that the formation of co-existing liquid ordered (Lo) domains rich in sphingolipids and cholesterol and liquid disordered (Ld) domains rich in unsaturated lipids, has an important role in cell membrane structure and function. Detergent TX-100 favorably partitions into and dissolves the Ld phase. It is used to isolate insoluble Lo-like membranes known as detergent resistant membrane (DRM) from cells. The relationship between DRM and pre-existing Lo domains in cells is not clear. We carried out experiments to find out how TX-100, and TM helices (which are cell membranes components), change membrane properties by investigating their effect on liposomes composed of brain sphingomyelin/1-palmitoyl-2-oleoyl-phosphatidylcholine/cholesterol. As measured by anisotropy and tempo quenching, methods that detect local environment at the nearest neighbor level, neither TX-100 nor TM helices affected the thermal stability of membrane order. In contrast, FRET, which detects proximity at longer length scales, detected that ordered domains disappeared at a lower temperature than that estimated from anisotropy or quenching, both with and without TX-100 and TM helices. FRET detected domains at higher temperatures in the presence of TX-100 or TM peptides than in their absence. The amount of ordered domains and their thermal stability appeared to increase as the interaction distance (Ro) of the FRET pair decreased. These differences are most easily explained by a difference in the size-sensitivity of the detection techniques, such that FRET is unable to detect Lo domains smaller than Ro in size, and by the conclusion that TX-100 increases ordered domain size. However, in presence of TM peptides, this increase in domain size is less evident, as the TM peptide by itself already increases domain size. Thus, in natural membranes the effect of TX-100 upon domain formation may not be significant.

Kinetics of brilliant green fading in the presence of TX-100, DTAB and SDS

The rate constant of alkaline fading of brilliant green (BG+) was measured in the presence of non ionic (TX-100), cationic (DTAB) and anionic (SDS) surfactants. This reaction was studied under pseudo first-order conditions at 283–303 K. The rate of reaction showed remarkable dependence on the electrical charge of the used surfactants. It was observed that the reaction rate constant increases in the presence of TX-100 and DTAB (catalytic effect) and decreases in the presence of SDS (inhibitory effect). Binding constants and the related thermodynamic parameters were obtained by the classical model. The results show that binding of BG+ to TX-100 is exothermic and binding of BG+ to DTAB and SDS is endothermic in the used concentration range of surfactants.

Kinetics Study of Malachite Green Fading in the Presence of TX-100, DTAB and SDS

The rate constants of alkaline fading of malachite green (<TEX>$MG^+$</TEX>) was measured in the presence of nonionic (TX-100), cationic (DTAB) and anionic (SDS) surfactants. This reaction was studied under pseudo-first-order conditions at 283∼303 K. The rate of fading reaction showed noticeable dependence on the electrical charge of the used surfactants. It was observed that the reaction rate constants were increased in the presence of TX-100 and DTAB and decreased in the presence of SDS. According to Hughs-Ingold rules for nucleophilic substitution reactions, the electric charge of MG/surfactant compound along with decrease in dielectric constant of <TEX>$MG^+$</TEX> micro-environment in this compound varies the rate of fading reaction. Binding constants of surfactant molecules to <TEX>$MG^+$</TEX> were calculated using cooperativity, pseudo-phase ion exchange and classical models and the related thermodynamic parameters were obtained by classical model. The results show that the binding of <TEX>$MG^+$</TEX> to TX-100 is exothermic and binding of <TEX>$MG^+$</TEX> to DTAB and SDS in some concentration ranges of the used surfactants is endothermic and in the other ones is exothermic.

Characterization of surfactant/hydrotalcite-like clay/glassy carbon modified electrodes: Oxidation of phenol

The characteristics of hydrotalcite (HT)-like clay films containing ionic and nonionic surfactants and their ability to oxidize phenol have been examined. The HT clay (Co/Al–NO 3) was synthesized by coprecipitation techniques and then modified with surfactants such as sodium dodecylbenzenesulfonate (SDBS), octylphenoxypolyethoxyethanol (TX100) or cetylpyridinium bromide (CPB). X-ray diffraction analysis revealed that the interlayer basal spacing varied depending on the type of surfactant retained by the HT. The presence of SDBS and CPB expanded the HT interlayer, which in the presence of TX100 did not show an appreciable change. Phenol oxidation is favored at surfactant-HT-GC modified electrodes, after a preconcentration time, compared to phenol oxidation at HT-GC or GC electrodes. Surfactant-HT-GC modified electrodes display good stability in continuous electrochemical phenol oxidation. At pH values between 6 and 10.8, both SDBS-HT-GC and TX100-HT-GC modified electrodes seem to be promising electrodes for the detection of phenol in water; while the CPB-HT-GC modified electrode should be affected by the inorganic anions.