表面活性剂溶胀胶束：性能及应用

溶胀胶束是表面活性剂胶束增溶其它物质后使胶束膨胀的一种胶束状态,因其能显著提高难溶性物质的溶解度而备受关注。针对近年来对溶胀胶束的研究进展,综述了溶胀胶束的最大增溶量、增溶过程以及增溶后形貌尺寸的变化等问题,总结了影响胶束增溶作用的因素,厘清了溶胀胶束与微乳液的异同,介绍了溶胀胶束的应用,展望了其应用前景与发展方向。     

Solubilization and Separation of Dicarboxylic Acids by Surfactant Micelles and Polyelectrolytes

Semi‐equilibrium dialysis (SED) and micellar enhanced ultra filtration (MEUF) methods are used to determine the extent of solubilization of water‐insoluble compounds by surfactant and polyelectrolyte. In this study, solubilization of ortho‐, meta‐ and para‐phthalic acids (OPA, MPA and TPA), 1,4‐ and 2,6‐naphthalene dicarboxylic acids (1,4‐NDCA and 2,6‐NDCA) into hexadecylpyridinium chloride (CPC), and the behavior of these acids to bind to the polyelectrolyte ionizable groups were investigated at 25 °C, using SED and MEUF methods. Polydimethyldiallylammonium chloride (PDMDAAC) is used in this study. It was found that the solubilization of organic acids decreases with increasing the solute mole fractions in micelles. Also, the best separation occurs at the lowest concentration of the phthalate ions and high concentrations of either CPC or PDMDAAC. The results support the idea of charge interaction between the anionic dicarboxylate groups and cationic surfactant or polyelectrolyte. The results also show that the presence of a second phenyl ring does not greatly affect the solubilization behavior of the acids.     

Stereoselective Aldol Reactions Catalyzed by Acyclic Amino Acids in Aqueous Micelles

The catalytic properties of all proteinogenic, acyclic amino acids for direct aldol reaction in H₂O, assisted by various surfactants, were investigated. The basic and neutral amino acids were shown to be efficient catalysts, giving rise to good‐to‐excellent yields of adducts (up to 95%), with moderate‐to‐good diastereoselectivities (up to 86%), L ‐arginine being the most‐effective catalyst. The syn/anti diastereoisomer ratio could be readily tuned by proper choice of the amino acid used. Also, the range of substrates that underwent the reaction was extended to less‐reactive aldehydes carrying electron‐donating Br substituents.     

Liquid Membrane Oscillation of Water/Oil/Water System Containing TTAB and Recognition to Amino Acids

The liquid membrane oscillation of a novel water(aqueous tetradecyl trimethyl ammoniumbromide,TTAB and alcohol solution)/oil(picric acid in chloroform solution)/water(aqueous glucose solution) system was investigated by means of a homemade device.The results show that the water(aqueous 7 mmol/L TTAB and 0.5 mol/L n-propanol solution)/oil(0.5 mmol/L icric acid in chloroform solution)/water(0.1 mol/L glucose solution) system performed sustained and stable oscillation at 30 °C.The oscillation curve under optim...     

Removal of Disperse Dyes from Water Using Surfactant Treated Alumina

An alumina surface was modified by adsorption of an anionic surfactant, sodium dodecyl sulfate (SDS). Typical S‐shaped isotherm of surfactant on alumina was observed. The adsorption of Disperse Red‐11, Disperse Blue‐26 and Disperse Red‐156 on alumina and surfactant treated alumina has been investigated. The enhancement in adsorption of these disperse dyes on surfactant treated alumina is observed, which may be attributed to their solubilization in surfactant aggregates formed at the solid/liquid interface. The effect of pH on adsorption has been studied. The adsorption is greatly influenced by pH of the medium. The applicability of the Langmuir model and the Dual‐Mode sorption model (DSM) were tested for equilibrium data.     

Removal of Fulvic Acids from Aqueous Solutions via Surfactant Modified Zeolite

IntroductionNatural organic matter(NOM)is composed of acomplex mixture of organic compounds derived fromliv-ing and dead plants,animals and microorganisms,waste products of animals and microorganisms,andfrom the degradation of the above materials[1].Fulvi…     

Analysis of the Amino Acids of Soy Globulins by AOT Reverse Micelles and Aqueous Buffer

The 7S and 11S globulins from soybean proteins using reverse micelle and aqueous buffer extraction methods were characterized by using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and scanning electron microscope (SEM), and their amino acid compositions were also evaluated. SDS-PAGE did not show electrophoretic differences between 7S and 11S globulin subunits with two extraction methods. SEM analysis showed that the AOT reverse micelle processing of 7S and 11S globulins induced a reduction of droplet size. Some individual amino acid contents of 7S and 11S globulins using two extraction methods were different, some were similar. In all the samples, the glutamic acid, aspartic acid, and leucine were the dominant amino acids while the cystine and methionine were the first-limiting amino acids. The proportion of essential amino acids to the total amino acids (E/T) of the 7S globulin from aqueous buffer and reverse micelles was similar. While significant differences were obtained in the proportion of E/T of the 11S globulin.     

交替三线性分解荧光二阶校正法同时直接测定口服液中氨基酸

酪氨酸(TYR)和色氨酸(TRY)的荧光光谱相互重叠,用常规方法难以同时直接测定。本研究将交替三线性分解二阶校正算法与激发发射矩阵荧光法相结合,对氨基酸口服液中共存的酪氨酸和色氨酸进行了同时分辨和直接定量测定,并用加入标准法对结果进行验证,TYR和TRY的回收率分别为(96.9±2.5)%和(93.2±1.0)%。结果表明,该方法以“数学分离”替代“化学分离”,其它成分及背景不影响其测定。     

Partitioning of Some Amino Acids in an Aqueous Surfactant Two-Phase System

Surfactants have found widespread uses in separation science, such as cloud-point extraction and coacervation with certain surfactants, two-phase separation has been studied and practiced for the separation of metal chelators,small organic molecules as well as biomacromolecules.     

Study on Production of Amino Acids from Bean Dregs by Hydrolysis in Sub-critical Water

This study investigated the production of value‐added amino acids from bean dregs by hydrolysis in subcritical water. It was investigated that the effect of reaction temperature, reaction time and CO₂ on amino acid concentration in the hydrolysates of bean dregs. The product of amino acid was determined by Amino Acid Analyzer. The results show that a variety of amino acids are produced. The concentrations of arginine, lysine and alanine were relatively high in the hydrolysate. Temperature and time have a great influence on the hydrolysis reaction. The effects of reaction temperature and time on concentration of different amino acids vary. The addition of carbon dioxide led to an increase in amino acid yield due to the acceleration of acid hydrolyzed catalysis steps. The highest yield of total amino acids is 22% (0.22 g/g of dry bean dregs) at 330°C and 30 min. This method may provide a practical and economical solution for the disposal of bean dregs wastes.     

Analysis of Thermal Decomposition Patterns of Aromatic and Heteroaromatic Amino Acids

Abstract

Differential enthalpic analysis of the thermal degradation of aromatic and heteroaromatic amino acids provides thermograms which are characteristic of specific amino acids (e.g. phenylalanine, tyrosine, tryptophan or histidine). Curve resolution of the resulting thermograms suggests that a minimum of three reactions are involved in the degradation (within the temperature limits of 500–620 [ddot]K) and provides T_M values for each of these concurrent reactions.     

Thermodynamics of Transfer of Amino Acids from Water to Aqueous Sodium Sulfate

Abstract

The solubilities of amino acids at 288.15, 298.15 and 308.15K in water and aqueous sodium sulfate have been determined as a function of electrolyte concentration (0.5, 1.0, 1.5 mol/kg of water). It has been observed that sodium sulfate renders amino acids less scluble. The free energies of transfer of amino acids from water to aqueous sodium sulfate have been calculated from the solubility data. The enthalpies and entropies of transfer have also been estimated. The solubility and the thermodynamics of transfer data manifest that sodium sulfate generates favourable interaction between nonpolar groups of amino acids. If applied to proteins, it seems to stabilize the protein native globular structure by enhancing the intramolecular nonpolar-nonpolar group interactions.     

Water Compatible Photoarylation of Amino Acids and Peptides

A novel photoarylation of amino acids and peptides is described, which tolerates the presence of water. Irradiation of Boc‐protected amino acids in the presence of N‐protected 2‐azidobenzimidazoles leads to selective arylation of carboxy termini or side chains. The new reaction also works for peptides. Irradiation of the nonapeptide H‐SPSYVYHQF‐OH also resulted in selective arylation of the tyrosine side chains, as indicated by ESI‐MS/MS fragmentation. Chemo‐ and regioselectivity could add the title reaction to the repertoire of photoaffinity labeling methods.     

Use of Micelles in the TLC Separation of Polynuclear Aromatic Compounds and Amino Acids

Abstract

The polynuclear aromatic compounds (PNA): anthracene, napthalene, phenanthrene, pyrene, pyrenecarboxaldehyde, benzo (a) pyrene, benzo (e) pyrene, perylene and fluorene can be chromatographed on polyamide TLC sheets using an aqueous micellar solution cf sodium dodecylsulfate (SDS) as the mobile phase. Reversed micellar solutions (of sodium dioctylsulfosuccinate) were used in a reverse phase chromatographic separation of amino acids. Some amino acids tended to streak slightly rather than move as discrete spots. Conditions could be adjusted, however, so that most of the amino acids and all PNA's would move as spots.     

蛋白质吸附表面活性剂的测定方法研究

一定ｐＨ值和一定浓度下，蛋白质与表面活性剂相互作用形成复合物产生沉淀。作者利用这一原理，研究了肌酸激酶对表面活性剂的吸附关系，并据此发展了滴定法和表面张力法两种简便测定蛋白质对表面活性剂吸附量的方法。     

四磺酸酞菁铜—DDAB表面活性剂薄膜电极对卤代乙酸的电化学催化

四磺酸酞菁铜阴离子（ＣｕＰｃＴｓ＾４－）在水溶液中可借助离子交换进入阳离子表面活性剂双十二烷基二甲基溴化铵（ＤＤＡＢ）薄膜电极，从而形成ＣｕＰｃＴＳ＾４－－ＤＤＡＢ薄膜电极，循环伏安实验表明，在ＫＢｒ溶液中，该薄膜电极有一对良好的还原氧化峰，阴阳极峤电位分别为－０．７８Ｖ和－０．６５Ｖ（ｖｓ．ＳＣＥ）．探讨了该薄膜电极的电化学行为，特别是对其各种卤代乙酸的电化学催化，对其机理进行了推测。     

离子选择电极法测定胶团的反离子结合度

胶团的反离子结合度(K)对于胶团各种性质的研究是一个至关重要的参数^[1～3]。已有不少方法用于K值的测定,其中以离子选择电极法最为方便^[4～8],且此法赋予K值的含义也与热力学要求相同^[9]。     

表面活性剂溶液油水界面相平衡研究

以Butler方程为基础,导出了1组通用的界面相平衡计算方程。利用此方程计算了多个实际体系,结果令人满意。根据实验现象及计算结果,提出了一种多组分界面相物理模型并探讨了表面活性物质在油水界面上的相互作用规律,为乳状液、微乳状液等研究提供了有益的信息。     

水溶液中磷酰基促进的成肽反应研究

水溶液中磷酰基促进的成肽反应研究沙耀武，巨勇，赵玉芬（清华大学化学系，北京，１０００８４）关键词磷酰化组氨酸，成肽，水溶液一些氨基酸在前生化时期的条件下，就可以由甲烷、氨和水通过高压放电生成［１，２］。如果向该反应体系中加入三氢化磷，生成的氨基酸的种...     

氨基酸从水到尿素水溶液中的迁移焓研究

用微量量热法测定甘氨酸、L-丙氨酸、L-丝氨酸在水和尿素水溶液中的溶解焓, 计算得到氨基酸从水到尿素水溶液的迁移焓, 并根据水合结构相互作用模型予以讨论. 结果表明, 氨基酸两性离子与尿素分子的静电作用以及两性离子头部与尿素分子的结构相互作用对氨基酸迁移焓有负贡献, 氨基酸侧链与尿素分子的结构相互作用依其亲水性或疏水性分别对迁移焓有负贡献或正贡献. 在实验浓度范围(0～13 mol/kg)内, 三种氨基酸的迁移焓总体上随尿素浓度的增加而下降, 其大小依次为L-丝氨酸＜甘氨酸＜L-丙氨酸, 氨基酸迁移焓的差异反映了溶质-溶剂结构相互作用的变化.