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Chinese Journal of Chemistry 2003年第12期21卷 1573-1579页

作者：王正武黄东阳宫素萍李干佐 Shantou University Medical College Shangdong Electric Power Central Hospital Key Lab of Colloid and Interface Chemistry for State Education Ministry Shandong University

In order to predict the critical micelle concentration (cmc) of nonionic surfactants in aqueous solution,a quantitative structure-property relationship (QSPR) was found for 77 nonionic surfactants belonging to eight series. The best-regressed model contained four quantum-chemical descriptors,the heat of formation (ΔH),the molecular dipole moment (D),the energy of the lowest unoccupied molecular orbital (E_ LUMO ) and the energy of the highest occupied molecular orbital (E_ HOMO ) of the surfactant molecule; two constitutional descriptors,the molecular weight of surfactant (M) and the number of oxygen and nitrogen atoms (n_ ON ) of the hydrophilic fragment of surfactant molecule; and one topological descriptor,the Kier & Hall index of zero order (KH0) of the hydrophobic fragment of the surfactant. The established general QSPR between lg(cmc) and the descriptors produced a relevant coefficient of multiple determination:R 2=0.986. When cross terms were considered,the corresponding best model contained five descriptors E_ LUMO ,D,KH0,M and a cross term n_ ON ·KH0,which also produced the same coefficient as the seven-parameter model.

关键词： quantitative structure-property relationship critical micelle concentration nonionic surfactant

Effect of polyoxypropylene chain length on the critical micelle concentration of propylene oxide-ethylene oxide block copolymers

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第3期6卷 219-221页

作者：张治国尹红 Department of Chemical Engineering Zhejiang University Hangzhou 310027 China

In this work, the surface activity of block copolymer nonionic surfactants (RPE) has been determined, i.e., critical micelle concentration (CMC), surface excess concentration (Γ), surface area demand per molecule (A), surface tension at CMC (γCMC). A linear decrease of ln[CMC] vs number of oxypropylene units in copolymer molecule was observed. The change in the work of cohesion per oxypropylene group when passing from molecular into micellar state, calculated from the Shinoda equation, was 0.43kT for the studied compounds.

关键词： Nonionic surfactant Propylene oxide-ethylene oxide block copolymers critical micelle concentration Micellization

Correlation of critical micelle concentration of Sodium Alkyl Benzenesulfonates with MolecularDescriptors

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Wuhan University Journal of Natural Sciences 2006年第2期11卷 409-414页

作者： LI Xuefeng ZHANG Gaoyong DONG Jinfeng ZHOU Xiaohai YAN Xiaoci LUO Mingdao College of Chemistry and Molecular Sciences Wuhan 430072 Hubei China

The hydrophobic-hydrophilic segment geometries of 36 sodium alkyl benzenesulfonates were fully optimized and calculated by abinitio RHF/6-31G（d）, quantum chemical data such as the charge density, the energy of molecular orbital and the dipole moment were obtained. Based on two topological descriptors and one quantum chemical descriptor, a significant quantitative structure-property relationship （QSPR） model for the critical micelle concentration （Cmc） of sodium alkyl benzenesulfonate surfactants was obtained by using the multiple linear regression technique. The good correlation coefficient of Re （0. 980） and cross-validation correlation coefficient Rcv^2 （0. 974） indicate the excellent capability and stability of the regression equation developed. In addition, linear relationships between logarithm of Cmc and the dipole moment of surfaetant hydrophobic hydrophilic segments for each homologous series have also been established with high correlation coefficient.

关键词： sodium alkyl benzenesulfonate critical micelle concentration RHF/6 31G(d)~ quantitative structure-property relationship multiple linear regression technique

Physico-chemical parameters for the assembly of moxifloxacin hydrochloride and cetyltrimethylammonium chloride mixture in aqueous and alcoholic media

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Chinese Journal of Chemical Engineering 2023年第5期57卷 280-289页

作者： Arnop Dutta Md.Tuhinur R.Joy Sk.Md.Ali Ahsan Mansour K.Gatasheh Dileep Kumar Malik Abdul Rub Md.Anamul Hoque Mohammad Majibur Rahman Nasrul Hoda D.M.Shafiqul Islam Department of Chemistry Jahangirnagar UniversitySavarDhaka 1342Bangladesh Department of Chemistry Jashore University of Science and TechnologyJashore 7408Bangladesh Department of Biochemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia Laboratory for Chemical Computation and Modeling Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh CityViet Nam Faculty of Applied Technology Van Lang UniversityHo Chi Minh CityViet Nam Center of Excellence for Advanced Materials Research King Abdulaziz UniversityJeddah 21589Saudi Arabia Chemistry Department Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Environmental Sciences Jahangirnagar UniversitySavarDhaka 1342Bangladesh Department of Neurology Henry Ford Health SystemDetroitMI 48292USA

The aggregation behavior of the mixture of cetyltrimethylammonium chloride(CTAC), a cationic surfactant, and moxifloxacin hydrochloride(MFH), a fourth-generation fluoroquinolone antibiotic drug, has been studied using the conductivity technique in aqueous and alcoholic(EtOH, 1-PrOH, and 2-BuOH)media. The study was performed at several temperatures between 298.15 and 323.15 K at 5 K *** assembly has been characterized by evaluating the micellar parameters, such as the critical micelle concentration(CMC) and the counter ion binding(β), of the CTAC + MFH mixture. The values of the CMC for the assembly of the CTAC + MFH mixture were reliant on the composition of alcohols in the mixed solvents and the temperature. The CMC values of the CTAC + MFH mixture increased with increasing temperature;that is, assembly was delayed by increased temperature. The micellization of the CTAC + MFH mixed system was delayed in alcoholic media. The observed-ΔG0mvalues for the association of the CTAC + MFH mixed system demonstrated a spontaneous aggregation process under all study *** on the-ΔH^(0)_(m) and +ΔS^(0)_(m) values, the association of the CTAC + MFH mixture is exothermic and the interaction forces acting between the CTAC and MFH species are hydrophobic, ion–dipole, and electrostatic interactions. The transfer properties and enthalpy–entropy compensation were also assessed and described comprehensively.

关键词： Moxifloxacin hydrochloride drug Aggregation Alcohol Hydrophobic interaction critical micelle concentration Thermodynamic properties

Complexation Induced by Weak Interaction between DNA and PEO-b-P4VP below the CMC of the Polymer

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Chinese Journal of Polymer Science 2017年第1期35卷 46-53页

作者： han miao ya-fen wang hai-yan dong 陈道勇 The State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Fudan University Shanghai 200433 China

The complexation between circular DNA and individual chains of PEO-b-P4VP with a relatively long PEO block and a short P4VP block is highly controllable when the interaction between DNA and the polymer is weak enough. When one circular DNA chain is taken into consideration, and the polymer concentration is far below its critical micelle concentration （CMC）, polymer chains are absorbed by DNA chain due to the interaction between the negatively charged DNA chain and the slightly positively charged P4VP block chains. After the adsorption/complexation, the DNA chain is converted into a nanoring （type 1）. In the nanoring, the DNA chain is sufficiently wrapped by the polymer and adopts a fully stretched conformation, so that the DNA compact ratio in the nanorings is close to 1. When the polymer concentration is close to but lower than the CMC, the free polymer chains in the solution are adsorbed not only by the DNA chain but also by the polymer chains that have already been adsorbed on the DNA chain. As a result, the circular DNA chain adsorbs more polymer chains, and thus the resultant nanoring （type 2） has a larger width. In the type 2 nanoring, the DNA chain is slightly compressed; the DNA compact ratio is only about 2-3. Therefore, complexation induced by the weak interaction between DNA and PEO-b-P4VP below the CMC can produce narrow-disperse and large nanorings with a perimeter of micrometers, which are difficult to prepare by existing methods.

关键词： Weak interaction DNA Individual polymer chains Block copolymer critical micelle concentration

Effects of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 on the peroxidase-catalyzed oxidation of 2-naphthol

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Journal of Environmental Sciences 2013年第7期25卷 1431-1440页

作者： Ivanec-Goranina Rūta Kulys Juozas Department of Chemistry and Bioengineering Faculty of Fundamental Sciences Vilnius Gediminas Technical University Institute of Biochemistry Vilnius University

The kinetics of the recombinant Coprinus cinereus peroxidase-catalyzed2-naphthol oxidationwas investigated in the presence of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 at pH 5.5 and25°C,with concentrations of （bio）surfactants both less than critical micelle concentrations （CMC） and larger than CMC. Itwas shown that monomers of JBR425 aswell as monomers of Surfynol465 had an enhancing effect on the conversion of2-naphthol indose response manner anddid not influence the initial rate of 2-naphthol oxidation. The resultswere accounted by a scheme,which contains a stadium of enzyme inhibition by oligomeric2- naphthol oxidation products. The action of the biosurfactant＇s （or synthetic surfactant＇s） monomerswas explained by avoidance of the enzyme active center clothingwith oligomers. Similar results havedemonstrated the potential of rhamnolipid biosurfactant JBR425due to its biodegradability. When biosurfactants＇ concentrations are larger than CMC, （bio）surfactants have an opposite effect on the oxidation of2-naphthol by peroxidase.

关键词： oxidation peroxidase biosurfactant critical micelle concentration

Influence of Structural Variations on Electrical Conductivity and Solubility of 1-Vinyl-3-alkylimidazole Halogen Ionic Liquids

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Journal of Wuhan University of Technology(Materials Science) 2014年第5期29卷 1090-1097页

作者：唐一梅 HU Xiaoling GUAN Ping LI Xiaoqian TIAN Tian School of Natural and Applied Sciences Northwestern Polytechnical University the Key Laboratory of Space Applied Physics and ChemistryMinistry of Education

Several 1-vinyl-3-alkylimidazolium halogens [VRIM]X, which are functional materials with ethylenic bonds, were synthesized using the microwave-assisted synthesis method. Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy were carded out to analyze the resultant structures. The electrochemical properties and solubility of [VRIM]Br were investigated and discussed in detail. The temperature dependence of pure [VRIM]Br over a wide temperature range of 298.15-323.15 K fitted the Arrhanius equation well. At certain low concentrations, the electrical conductivity of the [VRIM]Br solution significantly increased with increasing solution concentration. The electrical conductivities of the [VRIM]Br observed in water, methanol, and ethanol showed the trend σwater〉 σmethanol 〉σethanol Conductometry showed that the critical miceUe concentrations of the bromines in water, methanol, and ethanol were 6.8-6.9 × 10-6, 1.4-1.5 × 10-5, and 1.9-2.0×10-5 mol.L-1, respectively; these results indicate that [VRIM]Br is an excellent surfactant. The solubility of [VRIM]X in common solvents was determined at 293.15 K, and results indicated that a decrease in solubility could be observed with decreasing dielectric constant of the solvent, elongation of the alkyl chain of the cation, and increasing anion size. Solubility parameters were also determined according to the Hildebrand-Scoff equation.

关键词： 1-vinyl-3-alkylimidazole halogen ionic liquids solubility electrical conductivity critical micelle concentration

Synthesis and Surface Activity of Novel Triazole-based Cationic Gemini Surfactants

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Chinese Chemical Letters 2003年第6期14卷 653-656页

作者： Ling Guang QIU An Jian XIE Yu Hua SHEN School of Chemistry and Chemical Engineering Anhui UniversityHefei 230039 Institute of Solid State Physics Chinese Academy of SciencesHefei 230031

The synthesis and surfactant activities of two new cationic gemini surfactants containing triazole compound as spacer were described. Their critical micelle concentrations (CMC), which are 1.8×10-4 mol/L and 3.9×10-4 mol/L respectively, are much lower than that of conventional surfactant cetyltrimethyl ammonium chloride (CTAC). In addition, compared with some gemini surfactants containing phenylene, xylylene and stilbenyl as spacer, this new kind of surfactants has good solubility in water at room temperature because of containing more hydrophilic groups or atoms in molecules.

关键词： Gemini surfactant cationic surfactant critical micelle concentration triazole synthesis.

Synthesis and characterization of a novel amphiphilic biodegradable β-cyclodextrin/poly(γ-benzyl L-glutamate) copolymer

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Chinese Chemical Letters 2009年第3期20卷 362-365页

作者： Qiu Hua Wu Fang Liang Tian Zhu Wei Xi Ming Song Shu-Yao WU Guo Lin Zhang Key Laboratory of Green Synthesis and Preparative Chemistry of Advanced Materials (Liaoning University) The Education Department of Liaoning Province Shenyang 110036 China College of Chemistry Liaoning University Shenyang 110036 China

β-Cyclodextrin/poly（γ-benzyl L-glutamate）（β-CD-PBLG） copolymers were synthesized by ring-opening polymerization of N- carboxy-γ-benzyl L-glutamate anhydride （BLG-NCA） in N,N-dimethylformamide （DMF） initiated by mono-amino-β-cyclodextrin（H2N-β-CD）. The structures of the copolymers were confirmed by IR, ^1H NMR and GPC. The fluorescence technique was used to determine the critical micelle concentrations （CMC） of copolymer micell solution, the diameter and the distribution of micelles were characterized by DLS. The results showed that BLG-NCA could be initiated by H2N-β-CD to produce copolymer. The nanomicells were formed by these copolymers in water.

关键词： β-Cyclodextrin Poly(γ-benzyl-L-glutamate) Amphiphilic biodegradable copolymers critical micelle concentration

Synthesis and surface activity of a novel heterodouble chained N-acyltaurate amphiphile

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Chinese Chemical Letters 2007年第9期18卷 1071-1074页

作者： Feng Yan Zhi Cheng Xu Qing Tao Gong Zhi Qiang Jin Jing Yi An Sui Zhao Jia Yong Yu Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100080China Graduate School Chinese Academy of SciencesBeijing 100039China

A novel double chained amphiphile, N-(α-4-hexylphenoxy)-lauroyltaurate (abbreviated as 10 + 6B-T), has been synthesized. The structures of main intermediate products and the title product were characterized by 1H NMR. The new amphiphile shows high surface activity. The critical micelle concentration (cmc), which is 1.1 × 10?5 mol/L, is much lower than that of conventional double chained surfactants, such as sodium bis(2-ethylhexyl)sulfosuccinate (AOT).

关键词： Heterodouble chained surfactant Taurine critical micelle concentration Synthesis