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Jianbin Huang - One of the best experts on this subject based on the ideXlab platform.
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formation and phase transition of hydrogel in a zwitterionic Anionic Surfactant system
RSC Advances, 2015Co-Authors: Jianbin Huang, Haiming Fan, Shuzhi Zhao, Haijian Fan, Wanli KangAbstract:The phase behavior and microstructure in a mixture of the zwitterionic Surfactant N-hexadecyl-N,N-dimethyl-3-ammonio-1-propane sulfonate (HDPS) and Anionic Surfactant sodium dodecylsulfate (SDS) were studied. Analysis of its macroscopic appearance, tube inversion testing and rheological measurements were employed to characterize its phase behavior, and it was found that a hydrogel formed in an appropriate total concentration (CT) and molar percentage of SDS (XSDS) at 25 °C for HDPS/SDS systems. Microstructures in the hydrogel were identified to be long wormlike micelles and small spherical vesicles, using transmission electron microscopy (TEM). The coexistence of wormlike micelles and small vesicles brings an appropriate packing parameter (p), which indicates that the wormlike micelles reached a sufficient length and degree of entanglement to form the three-dimensional elastic hydrogel. The HDPS/SDS hydrogel transforms into a viscoelastic sol upon increasing the temperature, and the determined gel–sol transition temperature (Tg–s) has been determined to be around 30 °C, using optical and rheological methods. Besides, adding salt causes the wormlike micelles to lengthen and the rheological properties of the solution to change, such that it may even induce a sol–gel phase transition in the mixed zwitterionic and Anionic Surfactant system.
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Hydrotropic salt promotes Anionic Surfactant self-assembly into vesicles and ultralong fibers
Journal of colloid and interface science, 2011Co-Authors: Yiyang Lin, Xinhao Cheng, Yun Yan, Yan Qiao, Jianbin HuangAbstract:Abstract Molecular self-assembly has become a versatile approach to create complex and functional nanoarchitectures. In this work, the self-assembly behavior of an Anionic Surfactant (sodium dodecylbenzene sulfonate, SDBS) and a hydrotropic salt (benzylamine hydrochloride, BzCl) in aqueous solution is investigated. Benzylamine hydrochloride is found to facilitate close packing of Surfactants in the aggregates, inducing the structural transformation from SDBS micelles into unilamellar vesicles, and multilamellar vesicles. The multilamellar vesicles can transform into macroscale fibers, which are long enough to be visualized by the naked eye. Particularly, these fibers are robust enough to be conveniently separated from the Surfactant solution. The combined effect of non-covalent interactions (e.g., hydrophobic effect, electrostatic attractions, and π–π interactions) is supposed to be responsible for the robustness of these self-assembled aggregates, in which π–π interactions provide the directional driving force for one-dimensional fiber formation.
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special effect of β cyclodextrin on the aggregation behavior of mixed cationic Anionic Surfactant systems
Journal of Physical Chemistry B, 2009Co-Authors: Lingxiang Jiang, Dehai Liang, Yilin Wang, Manli Deng, Yun Yan, Jianbin HuangAbstract:Controllable aggregate transitions are achieved in this work by adding due amounts of beta-cyclodextrin (beta-CD) to mixed cationic/Anionic Surfactant aqueous solutions. In contrast to its "aggregate breaking" effect in single Surfactant systems, aggregate growth is observed in nonstoichiometrical mixed cationic/Anionic Surfactant systems upon addition of beta-CD. The aggregate growth typically undergoes a micellar elongation and a following micelle-to-vesicle transition, which in turn greatly influences the viscosity and absorbance of the solutions. A possible mechanism of this beta-CD-induced aggregate growth is proposed. In mixed cationic/Anionic Surfactant systems, the Surfactants strongly tend to reach electroneutral equilibrium in aggregates. In the present case, added beta-CD is found to greatly facilitate the equilibrium by transferring the "major" component (whose molar fraction>0.5) of a cationic/Anionic Surfactant mixture from the aggregates to beta-CD cavities. Consequently, the Surfactants in the aggregates approach electroneutral mixing, in favor of low-curved aggregates such as vesicles. This work shows that beta-CD provides an additional degree of freedom to control microstructures and macroproperties for the whole class of mixed cationic/Anionic Surfactant systems.
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ph regulated molecular self assemblies in a cationic Anionic Surfactant system from a 1 2 Surfactant pair to a 1 1 Surfactant pair
Langmuir, 2008Co-Authors: Yiyang Lin, Xue Han, Xinhao Cheng, Jianbin Huang, Dehai LiangAbstract:With the aid of pH variation, direct transformation of a “1−1” cationic−Anionic Surfactant pair to a “1−2” cationic−Anionic Surfactant pair was attained in the system of cetyltrimethylammonium bromide and n-decylphosphoric acid. Owing to the transformation of a “1−1” pair to a “1−2” pair, diverse microstructures and peculiar phase behavior in this cationic−Anionic Surfactant mixture was obtained at different pH. It is proposed that pH can be manipulated for effectively tailoring the self-assembled organization in this cationic−Anionic Surfactant system, including spherical micelle, wormlike micelle, vesicle, and lamellar structure. In contrast to the conventional “1−1” Surfactant pair, the “1−2” cationic−Anionic Surfactant pair exhibits unexpectedly weak aggregating ability. It is suggested that the hydrated volume of Surfactant headgroup should be taken into consideration to better elucidate the self-assembly behavior of these “1−2” cationic−Anionic Surfactant mixtures.
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temperature sensitive aqueous Surfactant two phase system formation in cationic Anionic Surfactant systems
Journal of Physical Chemistry B, 2007Co-Authors: Ke Wang, Haiqing Yin, Wei Sha, Jianbin HuangAbstract:Temperature-induced aqueous Surfactant two-phase system (T-ASTP), which was found to be of generic importance, was investigated in a series of conventional mixed cationic-Anionic Surfactant systems. On the basis of the investigations of turbidity, dynamic light scattering, transmission electron microscopy, and fluorescence resonance energy transfer, the formation of T-ASTP can be attributed to temperature-induced vesicle aggregation. Aggregated vesicles existed in the upper part, while the separated vesicles existed in the lower part. The phase separation temperature can be regulated by varying the Surfactant composition or adding additives, such as D-sorbitol, urea, or NaBr. The hydrophobic interaction and cooperative effect between cationic and Anionic Surfactants played a significant role in the formation of T-ASTP.
Hanqi Zhang - One of the best experts on this subject based on the ideXlab platform.
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determination of sudan i iv in candy using ionic liquid Anionic Surfactant aqueous two phase extraction coupled with high performance liquid chromatography
Food Chemistry, 2015Co-Authors: Zhongling Liu, Hanqi ZhangAbstract:Abstract Ionic liquid/Anionic Surfactant aqueous two-phase system was developed and applied for the extraction of Sudan I–IV. High-performance liquid chromatography was applied to the determination of the analytes. The aqueous two-phase system (ATPS) was formed in the present of C4[MIM]BF4, sodium dodecyl benzene sulphonate and (NH4)2SO4. The parameters affecting the extraction efficiency, such as volume of ionic liquid, amount of sodium dodecyl benzene sulphonate, ionic strength, pH value of system, extraction time and temperature were investigated. The limits of detection for Sudan I, II, III and IV were 5.45, 4.66, 3.68, 4.20 μg kg−1, respectively. When the present method was applied to the analysis of candy samples, the recoveries of the analytes ranged from 82.3% to 112.1% and relative standard deviations were lower than 7.41%.
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ionic liquid Anionic Surfactant based aqueous two phase extraction for determination of antibiotics in honey by high performance liquid chromatography
Talanta, 2014Co-Authors: Xiao Yang, Zhongling Liu, Shaohua Zhang, Lei Lei, Hanqi ZhangAbstract:Abstract An ionic liquid-Anionic Surfactant based aqueous two-phase extraction was developed and applied for the extraction of tetracycline, oxytetracycline and chloramphenicol in honey. The honey sample was mixed with Na 2 EDTA aqueous solution. The sodium dodecyl sulfate, ionic liquid 1-octyl-3-methylimidazolium bromide and sodium chloride were added in the mixture. After the resulting mixture was ultrasonically shaken and centrifuged, the aqueous two phase system was formed and analytes were extracted into the upper phase. The parameters affecting the extraction efficiency, such as the volume of ionic liquid, the category and amount of salts, sample pH value, extraction time and temperature were investigated. The limits of detection of tetracycline, oxytetracycline and chloramphenicol were 5.8, 8.2 and 4.2 μg kg −1 , respectively. When the present method was applied to the analysis of real honey samples, the recoveries of analytes ranged from 85.5 to 110.9% and relative standard deviations were lower than 6.9%.
J. Penfold - One of the best experts on this subject based on the ideXlab platform.
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Anionic Surfactant biogenic amine interactions the role of Surfactant headgroup geometry
Journal of Colloid and Interface Science, 2016Co-Authors: J. Penfold, R. K. ThomasAbstract:Oligoamines and biogenic amines (naturally occurring oligoamines) are small flexible polycations. They interact strongly with Anionic Surfactants such as sodium dodecyl sulfate, SDS. This results in enhanced adsorption and the formation of layered structures and the formation of layered structures at the air-water interface which depends on Surfactant concentration and solution pH. The effect of changing the Surfactant headgroup geometry on that interaction and subsequent adsorption is reported here. Neutron reflectivity, NR, results for the surface adsorption of the Anionic Surfactant sodium diethylene glycol monododecyl ether sulfate, SLES, with the biogenic amine, spermine, are presented, and contrasted with previous data for SDS/spermine mixtures. The enhancement in the adsorption of the Surfactant at the air-water interface where monolayer adsorption occurs is similar for both Surfactants. However the regions of Surfactant concentration and solution pH where surface multilayer adsorption occurs is less extensive for the SLES/spermine mixtures, and occurs only at low pH. The results show how changing the headgroup geometry by the introduction of the ethylene oxide linker group between the alkyl chain and sulfate headgroup modifies the polyamine - Surfactant interaction. The increased steric constraint from the polyethylene oxide group disrupts the conditions for surface multilayer formation at the higher pH values. This has important consequences for applications where the modification or manipulation of the surface properties are required.
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ion specific effects in trivalent counterion induced surface and solution self assembly of the Anionic Surfactant sodium polyethylene glycol monododecyl ether sulfate
Langmuir, 2014Co-Authors: J. Penfold, R. K. Thomas, Jordan T. Petkov, I Tucker, John R P Webster, Isabelle Grillo, Alvin V TerryAbstract:The effect of different trivalent counterions, Al3+, Cr3+, Sc3+, Gd3+, and La3+, on the surface adsorption and Al3+, Cr3+, and Sc3+ for solution self-assembly of the Anionic Surfactant sodium polyethylene glycol monododecyl ether sulfate has been studied by neutron reflectivity and small angle neutron scattering. The strong binding and complexation between the trivalent counterions and the Anionic Surfactant result in significant micellar growth and the formation of surface multilayer structures at the air–water interface at relatively low counterion concentrations. Broadly similar surface and solution behaviors are observed for the different trivalent counterions. The evolution in the surface and solution structures in detail depends upon the nature of the counterion, its hydrated radius and its strength of binding. Exceptionally the addition of Cr3+ counterions have a less pronounced effect. This is attributed to a greater reluctance for exchange within the primary hydration shell for Cr3+ ions, which r...
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adsorption of model perfumes at the air solution interface by coadsorption with an Anionic Surfactant
Langmuir, 2013Co-Authors: Robert Bradbury, R. K. Thomas, Jordan T. Petkov, J. Penfold, I Tucker, Craig JonesAbstract:The adsorption of the model perfumes phenyl ethanol, PE, and linalool, LL, at the air–solution interface by coadsorption with the Anionic Surfactant sodium dodecyl 6-benezene sulfonate, LAS-6, has been studied primarily by neutron reflectivity, NR. The variation in the mixed surface adsorption with solution composition is highly nonideal, and the more hydrophobic LL is more surface active. At a LAS-6 concentration of 0.5 mM the adsorption of PE and LL is broadly similar but with the LL systematically more surface active, and at 2 mM the LL completes more effectively for the surface than the PE. The variation in surface composition with solution composition and concentration reflect the greater hydrophobicity and hence surface activity of LL, and the greater solubility of PE in aqueous solution. Changing the geometry of the LAS isomer, from the symmetrical LAS-6 geometry to the more asymmetrical LAS-4, results in the LL competing more effectively for the surface due to changes in the packing constraints as...
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solution self assembly of the sophorolipid bioSurfactant and its mixture with Anionic Surfactant sodium dodecyl benzene sulfonate
Langmuir, 2011Co-Authors: J. Penfold, Minglei Chen, Robert Thomas, Chuchuan Dong, Thomas J Smyth, Amedea Perfumo, Roger Marchant, Ibrahim M Banat, Paul Stevenson, Alyn James ParryAbstract:The self-assembly in aqueous solution of the acidic (AS) and lactonic (LS) forms of the sophorolipid bioSurfactant, their mixtures, and their mixtures with Anionic Surfactant sodium dodecyl benzene sulfonate, LAS, has been studied using predominantly small-angle neutron scattering, SANS, at relatively low Surfactant concentrations of <30 mM. The more hydrophobic lactonic sophorolipid forms small unilamellar vesicles at low Surfactant concentrations, in the concentration range of 0.2 to 3 mM, and transforms via a larger unilamellar vesicle structure at 7 mM to a disordered dilute phase of tubules at higher concentrations, 10 to 30 mM. In marked contrast, the acidic sophorolipid is predominantly in the form of small globular micelles in the concentration range of 0.5 to 30 mM, with a lower concentration of larger, more planar aggregates (lamellar or vesicular) in coexistence. In mixtures of AS and LS, over the same concentration range, the micellar structure associated with the AS sophorolipid dominates the...
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The role of electrolyte and polyelectrolyte on the adsorption of the Anionic Surfactant, sodium dodecylbenzenesulfonate, at the air-water interface.
Journal of colloid and interface science, 2011Co-Authors: X. L. Zhang, D. J. F. Taylor, Robert K. Thomas, J. PenfoldAbstract:Abstract The role of the polyelectrolyte, poly(ethyleneimine), PEI, and the electrolytes NaCl and CaCl2, on the adsorption of the Anionic Surfactant, sodium dodecylbenzenesulfonate, LAS, at the air–water interface have been investigated by neutron reflectivity and surface tension. The surface tension data for the PEI/LAS mixtures are substantially affected by pH and the addition of electrolyte, and are consistent with a strong adsorption of surface polymer/Surfactant complexes down to relatively low Surfactant concentrations. The effects are most pronounced at high pH, and this is confirmed by the adsorption data obtained directly from neutron reflectivity. However, the effects of the addition of PEI and electrolyte on the LAS adsorption are not as pronounced as previously reported for PEI/SDS mixtures. This is attributed primarily to the steric hindrance of the LAS phenyl group resulting in a reduction in the ion–dipole attraction between the LAS sulfonate and amine groups that dominates the interaction at high pH.
Zhiqiang Zhou - One of the best experts on this subject based on the ideXlab platform.
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determination of carbaryl and its metabolite 1 naphthol in water samples by fluorescence spectrophotometer after Anionic Surfactant micelle mediated extraction with sodium dodecylsulfate
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2007Co-Authors: Guifang Jia, Jing Qiu, Xinquan Wang, Wentao Zhu, Ying Sun, Zhiqiang ZhouAbstract:Anionic Surfactant micelle-mediated extraction with sodium dodecylsulfate (SDS) was applied as preconcentration step prior to fluorescence spectrophotometer without further cleanup step. The obtained Surfactant-rich phase was diluted to a fixed volume with water-miscible solvents. Carbaryl and its metabolite 1-naphthol were used as test compounds. The detection limits (LODs) of the method were in the microgram per liter area. Recoveries obtained from four real water samples ranged from 90.7 to 98.6%. Under the optimum experimental conditions, the method described showed a good precision, with relative standard deviations (R.S.D.) of less than 6%. According to the results, this approach reduced the viscidity of the Surfactant-rich phase and made the combination of fluorescence spectrophotometer with Anionic Surfactant micelle-mediated extraction much easier.
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determination of etofenprox in environmental samples by hplc after Anionic Surfactant micelle mediated extraction coacervation extraction
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Guifang Jia, Qiuxia Wang, Jing Qiu, Wenjing Zhou, Zhiqiang ZhouAbstract:A method is described for determination of residues of the insecticide Etofenprox in environmental samples. Anionic Surfactant micelle-mediated extraction (coacervation extraction) was evaluated for isolation of Etofenprox before HPLC. The optimum conditions used for extraction included: 0.09 g sodium dodecanesulfonate (SDoS), 3.1 mL (3.3, for concentrations below 0.04 mg L−1) 12 mol L−1 HCl, 5 min vortex stirring, 5 min centrifugation at 4000 rpm, 2 h equilibration time. The limits of quantification (LOQ) and detection (LOD) were 0.01 and 0.004 mg L−1, respectively, and recoveries obtained from five real samples ranged from 94.33±2.48 to 100.13±2.71%. The precision of the method was good; relative standard deviations (RSD) were less than 7%.
Zhongling Liu - One of the best experts on this subject based on the ideXlab platform.
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determination of sudan i iv in candy using ionic liquid Anionic Surfactant aqueous two phase extraction coupled with high performance liquid chromatography
Food Chemistry, 2015Co-Authors: Zhongling Liu, Hanqi ZhangAbstract:Abstract Ionic liquid/Anionic Surfactant aqueous two-phase system was developed and applied for the extraction of Sudan I–IV. High-performance liquid chromatography was applied to the determination of the analytes. The aqueous two-phase system (ATPS) was formed in the present of C4[MIM]BF4, sodium dodecyl benzene sulphonate and (NH4)2SO4. The parameters affecting the extraction efficiency, such as volume of ionic liquid, amount of sodium dodecyl benzene sulphonate, ionic strength, pH value of system, extraction time and temperature were investigated. The limits of detection for Sudan I, II, III and IV were 5.45, 4.66, 3.68, 4.20 μg kg−1, respectively. When the present method was applied to the analysis of candy samples, the recoveries of the analytes ranged from 82.3% to 112.1% and relative standard deviations were lower than 7.41%.
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ionic liquid Anionic Surfactant based aqueous two phase extraction for determination of antibiotics in honey by high performance liquid chromatography
Talanta, 2014Co-Authors: Xiao Yang, Zhongling Liu, Shaohua Zhang, Lei Lei, Hanqi ZhangAbstract:Abstract An ionic liquid-Anionic Surfactant based aqueous two-phase extraction was developed and applied for the extraction of tetracycline, oxytetracycline and chloramphenicol in honey. The honey sample was mixed with Na 2 EDTA aqueous solution. The sodium dodecyl sulfate, ionic liquid 1-octyl-3-methylimidazolium bromide and sodium chloride were added in the mixture. After the resulting mixture was ultrasonically shaken and centrifuged, the aqueous two phase system was formed and analytes were extracted into the upper phase. The parameters affecting the extraction efficiency, such as the volume of ionic liquid, the category and amount of salts, sample pH value, extraction time and temperature were investigated. The limits of detection of tetracycline, oxytetracycline and chloramphenicol were 5.8, 8.2 and 4.2 μg kg −1 , respectively. When the present method was applied to the analysis of real honey samples, the recoveries of analytes ranged from 85.5 to 110.9% and relative standard deviations were lower than 6.9%.