微乳液、胶束、反胶束(团)有序体系在化学分析与分离技术中的应用

简要介绍了两亲分子聚集体的分类,主要从微乳液的增效作用、胶束增溶及反胶团萃取技术等方面讨论了两亲分子聚集体在化学分析与分离技术中的应用进展,并展望了聚集体化学的应用前景。     

关于液/液萃取体系中聚集作用的综述--对普适模型的重新评估

综述近十年液/液萃取体系中聚集作用研究所取得的成果,认为已有必要对"普适模型"进行重新评估和讨论,得到以下结论:(1)酸性萃取剂分子在金属离子萃取过程中可能生成以反向胶团(reversed micelles)形式存在的聚合物,该聚合物在极大程度上取决于金属络合物的结构.酸性萃取剂在有机相中的二聚体(dimers)不直接参与聚集而往往是以酸盐复合体形式存在于聚集体中,不同品种的反向胶团或W/O型微乳状液之间不易相互渗透或缔合成单一聚集体.(2)萃取剂分子和金属离子(包括碱金属一价离子)的水化作用在形成胶团或W/O型微乳状液过程中起极重要作用,以至于可看作是这一过程的推动力.(3)研究了NaDEHP/正庚烷双连续型微乳状液,发现其\\"水池"中各组分行为甚为规范,与AOT/正庚烷W/O微乳状液极为相似.(4)以前所建议的聚合物的生成模型---普适模型在化学本质上与用反向胶团或W/O型微乳状液进行萃取的萃合物相同.化学反应也一样.(5)普适模型适用于碱金属和碱土金属的萃取,有条件地适用于过渡金属的镍的体系,但是钴体系极特殊,是一例外,而对稀土金属的萃取则不适用.     

反胶团法提取细胞色素－C

以细胞色素ｃ（ｃｙｔ－Ｃ）为对象，研究了水相ｐＨ值和离子强度对反胶团法萃取和反萃取ｃｙｔ－Ｃ的影响；讨论了不同种类的表面活性剂的萃取机理。研究结果表明，选择合适的体系及条件，反胶团提取是实现蛋白质分离提纯的有效方法。     

反胶团提取脂肪酶动力学研究：（Ⅱ）反萃取过程

研究以ＡＯＴ／异辛烷反胶团溶液的反萃取脂肪酶动力学,通过改变水相ｐＨ值,离子强度,搅拌速度和反胶团中脂肪酶浓度来测定总质量传质系数。结果表明,传质系数与水相的ｐＨ值,离子强度有关,而与搅拌速度,反胶团中脂肪酶浓度无关,说明该反萃取过程属于界面控制,进而提出反萃取过程机理。     

DNNSA反胶团萃取净化含镍电镀废水研究

研究了油水比、萃取剂浓度、萃取时间等对DNNSA反胶团萃取净化含镍电镀废水性能的影响,并采用图解法对逆流萃取理论级数进行了研究.结果表明:有机相煤油负载DNNSA反胶团萃取净化含镍电镀废水是可行的;提高油水比可以提高萃取效率;萃取时间为20 min达到萃取平衡;萃取剂浓度由0.005 7 M升高到0.446 M时,萃取效率提高了66.81%,即提高有机相中反胶团的数量有利于萃取反应的进行;DNNSA浓度为0.1 M时,其萃取容量约为3.57 g.L-1,多级逆流萃取理论级数为4级.     

反胶团法萃取质粒DNA

采用新的TOMAC(甲基三辛基氯化铵)/2-乙基己醇/异辛烷反胶团体系,对该反胶团萃取质粒pUT649进行了研究.考察了表面活性剂浓度、离子浓度等对质粒DNA萃取的影响.当采用1.0%(volume)2-乙基己醇/异辛烷为有机相,TOMAC浓度为40 mmol.L-1,水相初始DNA浓度为25μg.mL-1时,质粒pUT649的萃取率可达90%以上.离子浓度对萃取过程有重要影响,反萃取时通过调节水相中的离子浓度,可以实现DNA和RNA的分离.研究结果表明,TOMAC/2-乙基己醇/异辛烷反胶团体系适合于核酸的萃取和纯化.     

反胶团体系中的蛋白质分离和酶催化反应

反胶团是表面活性剂在有机溶剂中形成的，有机相中的每个反胶团可提供一个极性中心，其溶解部分水之后形成“水池”。为酶和蛋白质提供了生存的环境。反胶团体系可以萃取水溶液中的蛋白质，静电作用决定了蛋白质在两相的分配。水溶液的ｐＨ值和离子强度是主要影响因素，反胶团体系中的酶催化反应的动力学行为与水溶液体系基本一致。     

含磷及含氮农药稀溶液萃取分离的研究

农药生产废水对环境产生了极大的危害。该文在分析农药亲油性的基础上,对含磷及含氮农药稀溶液的萃取平衡特性作了较为系统的研究。研究表明,溶质的亲油性可以作为选择萃取溶剂的依据。溶质的亲油性和溶剂的极性、萃水率是影响物理萃取分配系数的重要因素,络合剂的种类、浓度以及稀释剂的种类、溶质的亲油性都会影响络合萃取的分配系数。在研究农药萃取分离特性的基础上,采用农药稀溶液进行了错流萃取研究,溶剂萃取前后溶液生物降解性的比较表明,萃取置换－生物处理法治理难降解有机废水具有很大的潜力     

反胶团或微乳液萃取蛋白质的研究

结合我们的研究结果，对反胶团或微乳液萃取蛋白质的原理、影响因素等进行了分析和讨论，并预示了该研究领域的发展趋势及应用前景。     

不同浓度AOT对猪心提取液中细胞色素C的萃取研究

用浓度（ｍｍｏｌ／Ｌ）１０、２５、５０、１００、１５０的ＡＯＴ（气溶胶ＯＴ）组成的反胶团对猪心肉糜提取液中的细胞色素Ｃ进行了萃取。结果为１０ｍｍｏｌ／Ｌ组几乎没有萃取效果，在２５～１５０ｍｍｏｌ／Ｌ浓度下的反胶团均有明显的萃取效果，萃取率（反萃取水相中的含量与原液中的含量的比值）还原型细胞色素Ｃ为２５％～３２％，氧化型细胞色素Ｃ为２８％～４２％．     

水相中奎宁分子印迹聚合物的制备、表征及识别性质的研究

以奎宁分子为模板,甲基丙烯酸为功能单体,在亲水体系中,利用两步种子溶胀和微乳液聚合的分子印迹技术,通过条件优化,成功制备得到一种单分散性好的球形分子印迹聚合物.用红外光谱、热重分析、电镜扫描、粒度分析等技术对聚合物进行了表征.通过聚合物在不同溶剂中的吸附量的变化,揭示采用酸性的功能单体MAA制得的聚合物可与带胺基的模板分子通过氢键、离子键(静电)相互作用,且识别机理随溶剂类型改变而改变.对不同底物的选择性实验表明该聚合物对模板分子具有良好的识别能力和选择性.     

复杂“星形”表面活性聚合物自组装行为的耗散粒子动力学模拟

表面活性聚合物因其改变溶液表面张力的功能,广泛应用于医疗以及化工领域.在溶液中表面活性聚合物自组装形成胶束形态决定溶液的流变性,影响自组装结构形成的因素是其研究的热点.采用耗散粒子动力学模拟方法,考察了多臂“星形”表面活性聚合物的自组装结构,通过改变表面活性聚合物链的亲疏水性,亲水基团和疏水基团的种类以及表面活性聚合物结构探索了各因素对“星形”表面活性聚合物自组装行为的影响.结果表明:“星形”表面活性聚合物能够自组装形成球形、层状、柱状/管状及囊泡胶束,溶剂条件、疏水链长度及亲疏水基团种类对胶束形态作用显著,囊泡变形规律受次级拓扑结构作用明显.     

反相微乳液中血红蛋白生物催化聚合芳杂环高分子

血红蛋白在双[2-乙基己酯]-磺酸基琥珀酸钠(Aerosol OT,AOT)形成的反相微乳液胶束中,在过氧化氢的存在下生物催化聚合邻苯二胺,所得产物与化学法合成的聚合物的热稳定性相当.推测所得产物为含有2,3-二氨基吩嗪和喹喔啉重复单元的芳杂环高分子纳米结构材料.     

疏水凝胶及疏水相互作用研究进展

综述了近年来疏水凝胶及疏水相互作用研究的最新进展．详尽地报道了该类凝胶的合成与表征方法，探讨了凝胶结构与性能的直接关系，介绍了疏水作用的定量描述方法和疏水作用的物理场论．深入研究凝胶中的疏水相互作用，对于揭示疏水凝胶对药物的控释机理和缓释机理有非常重要的意义．     

Helical self-assembled polymers from cooperative stacking of hydrogen-bonded pairs

The double helix of DNA epitomizes this molecule's ability to self-assemble in aqueous solutions into a complex chiral structure using hydrogen bonding and hydrophobic interactions. Non-covalently interacting molecules in organic solvents are used to design systems that similarly form controlled architectures. Peripheral chiral centres in assemblies and chiral side chains attached to a polymer backbone, have been shown to induce chirality at the supramolecular level, and highly ordered structures stable in water are also known. However, it remains difficult to rationally exploit non-covalent interactions for the formation of chiral assemblies that are stable in water, where solvent molecules can compete effectively for hydrogen bonds. Here we describe a general strategy for the design of functionalized monomer units and their association in either water or alkanes into non-covalently linked polymeric structures with controlled helicity and chain length. The monomers consist of bifunctionalized ureidotriazine units connected by a spacer and carrying solubilizing chains at the periphery. This design allows for dimerization through self-complementary quadruple hydrogen bonding between the units and solvophobically induced stacking of the dimers into columnar polymeric architectures, whose structure and helicity can be adjusted by tuning the nature of the solubilizing side chains.     

水溶性高分子金属卟啉络合物的合成及其与DNA作用的研究

利用荧光探针技术和圆二色谱等分析手段对两种水溶性高分子金属卟啉络合物同DNA的作用进行了初步研究．实验表明,所合成的高分子金属卟啉络合物在同DNA作用时存在有嵌入模式,金属卟啉络合物大的平面环疏水结构和亲水性基团的引入促进了这种作用．     

[CH3ONO2]H+正离子与R-OH型分子相互作用的DFT研究

用密度泛函(DFT)(B_³LYP) 方法,在6-31G(d,p)基组水平上优化了两种质子化的硝酸甲酯异构体几何构型和能量,研究了异构体与H₂O、CH₃OH等分子之间的氢键的相互作用,提出了氢键超分子复合物的两种平面结构。研究发现在酯位质子化异构体的相对稳定性高于在硝氧位质子化的异构体。但当异构体在液相中与ROH类分子发生分子间相互作用后这一顺序发生了反转,说明了该体系中的分子间相互作用对异构体较强的影响。     

Preparation and Characterization of Polymeric Micelles from Poly（D, L-lactide） and Methoxypolyethylene Glycol Block Copolymers as Potential Drug Carriers

Amphiphilic diblock copolymers composed of methoxy polyethylene glycol (MePEG) and poly(D,L- lactide) (PDLLA) were prepared for the preparation of polymeric micelles. The use of MePEG-PDLLA as drug carriers has been reported in the open literature, but there are only few data on the application of a se- ries of MePEG-PDLLA copolymers with different lengths in the medical field. The shape of the polymeric mi- celles is also important in drug delivery. Studies on in vitro drug release profiles require a good sink condi- tion. The critical micelle concentration of a series of MePEG-PDLLA has a significant role in drug release. To estimate their feasibility as a drug carrier, polymeric micelles made of MePEG-PDLLA block copolymer were prepared by the oil in water (O/W) emulsion method. From dynamic light scattering (DLS) measurements, the size of the micelle formed was less than 200 nm. The critical micelle concentration of polymeric micelles with various compositions was determined using pyrene as a fluorescence probe. The critical micelle con- centration decreased with increasing number of hydrophobic segments. MePEG-PDLLA micelles have a considerably low critical micelle concentration (0.4-0.5 μg/mL), which is apparently an advantage in utilizing these micelles as drug carriers. The morphology of the polymeric micelles was observed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The micelles were found to be nearly spherical. The yield of the polymeric micelles obtained from the O/W method is as high as 85%.     

Review on aggregation of acid extractants in solvent extraction of metal ions: remark on the general model

The aggregation behavior of various acid extractants in the solvent extraction systems of metal ions is re-examined and explained according to knowledge obtained in recent work. The conclusions are as follows. (1) Complexes formed by the extractants and metal ions can form reversed micelles in organic diluents, depending on the microstructures of the complexes. The dimers of the acid extractant cannot percolate to the metal-extractant aggregates, and the acid-salt complexes are always formed in the aggregates. The reversed micelles or the W/O microemulsions formed by different species cannot be associated with each other to form a unified aggregate. (2) In solvent extraction systems, hydration of the extractants and metal ions can be considered as the driving force of forming reversed micelles. (3) Information of the first approach to the insight of the bicontinuous microemulsion of NaDEHP shows that various components in the aqueous phase behave confined and very similar to the typical AOT/n-heptane W/O microemulsions. (4) In the extraction of lanthanide ions by the W/O microemulsion of sodium naphthenate, the saponification is a process of forming reversed micelle or W/O microemulsion, while the extraction step is a process of destroying reversed micelles or W/O microemulsion droplets.