大环分子载体液膜传输--一种新型的分离技术

大环主体分子能选择地与客体分子如金属离子,中性分子结合,这一特性使其可作为液膜分离的高选择性载体。评述了大环超分子载体的液膜传输的数学模型以及在金属阳离子,中性离子,中性分子,氨基酸的传输,协同传输中的应用。     

杯[4]芳烃衍生物对Pb2＋的液膜传输动力学

以3类含不同基团的杯[4]芳烃衍生物作为离子载体在H2O-CHCl3-H2O液膜传输体系下分别对Pb2＋进行液膜传输实验. 简要讨论了以杯[4]芳烃衍生物作为离子载体对Pb2＋液膜传输的动力学机理. 重点研究了不同载体种类, 载体浓度, 搅拌速度, 传输时间等因素对Pb2＋传输的影响. 实验结果表明: 以含Br原子的杯[4]芳烃衍生物和含S原子的杯[4]芳烃衍生物作为离子载体对Pb2＋有明显的传输效果. 可以用本文的动力学模型来描述整个传输体系的动力学特性.     

有机掺杂体系中的光生载流子的产生

研究苯基取代的聚苯撑乙烯共聚物PhPPV和盘状液晶分子HBC-PhC12掺杂不同比例的酰亚胺分子PDI体系的稳态光电流行为.结果表明,PDI含量在0.1%～10%范围时,光生载流子的量子效率与体系的种类和掺杂剂含量无关;PDI含量>10%时,与未掺杂时相比,光生载流子的产率增加2～3个数量级.     

Transport of Ca^2＋ Ion through a Bubbling Pseudo—emulsion Liquid Membrane with Calixarenes and Calixcrowns as Carriers

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Piezoelectric Crystal Membrane Chemical Sensors Based on Fullerene and Macrocyclic Polyethers

Various reusable and sensitive piezoelectric (PZ) quartz crystal membrane sensors with home‐made computer interfaces for signal acquisition and data processing were developed to detect organic/inorganic vapors and organic/inorganic/biologic species in solutions, respectively. Fullerene(C60), fullerene derivatives and artificial macrocyclic polyethers, e.g., crown ethers and cryptands, were synthesized and applied as coating materials on quartz crystals of the PZ crystal sensors. The oscillating frequency of the quartz crystal decreased due to the adsorption of organic or inorganic species onto coating material molecules on the crystal surface. The crown ether‐coated PZ crystal gas detector exhibited high sensitivity with a frequency shift range of 10–340 Hz/(mg/L) for polar organic gases, a short response time (< 2.0 min.), good selectivity, and good reproducibility. The Ag(I)/crptand22 and Ru(III) / crptand22 coated PZ gas detectors were also prepared for nonpolar organic vapors, e.g., alkynes and alkenes. The frequency shifts of the nonpolar PZ sensors were in the order: alkynes > alkenes > alkanes. A Ti(IV)/Cryptand22‐coated PZ crystal sensor was also developed to detect the inorganic air pollutants, e.g., CO and NO₂. A piezoelectric gas sensor for both polar/nonpolar organic vapors based on C60‐cryptand22 was also prepared. The cryptand22‐coated PZ gas sensor was also employed as a GC detector for organic molecules. The cryptand22‐coated piezoelectric GC detectors compared well with the commercial thermal conductivity detector (TCD). The interaction between fullerene C60 and organic molecules was studied with a fullerene coated PZ gas detector. A multi‐channel PZ organic gas detector with PCA(Principal Component Analysis) and BPN (Back Propagation Neural) analysis methods was developed. Various liquid piezoelectric crystal sensors based on long‐chain macrocyclic polyethers, e.g., C₁₀H₂₁‐dibenzo‐16‐crown‐5, C₁₈H₃₇‐benzo‐15‐crown‐5, (C₁₇CO)₂‐cyptand22 and fullerene derivatives, e.g., C60‐NH‐cryptand22 and dibenzo‐16‐crown‐5‐C60, were also developed as HPLC detectors for metal ions, anions, and various organic compounds in solutions. The sensitive and highly selective PZ bio‐sensors based on enzymes, polyvinylaldehyde, polycinnaldehyde‐C60 and C60‐cryptand22 were developed to detect various biologic species, e.g., proteins, glucose, and urea. A quite sensitive EQCM (Electrochemical Quartz Crystal Micro‐balance) detection system was also developed for detection of trace heavy metal ions.     

基于大环合成受体的超分子纳米阀门

在特定外界刺激下, 修饰于介孔纳米材料表面的超分子纳米阀门可以有效地控制所包封物质如药物模型分子、 抗癌药物分子和寡核酸等生物分子的靶向释放, 在药物释放、 基因转染及传感等领域有广泛的应用前景. 本文结合本课题组的工作, 综述了国内外在基于大环合成受体的超分子纳米阀门体系的化学构筑及功能等方面的研究进展.     

Environmental Effect of Macrocyclic Molecules on the Oxidation of Triethylamine by Ferricyanide Ion in Aqueous Solution

The effect of 18-crown-6 and kryptofix (2,2,1) on the oxidation of triethylamine byaqueous ferricyanide ion has been studied at pH 4, 7, and 9.The macrocycle retarded the normal oxidation process at all pH values,the effect depending on the macrocyclic ligand concentration Kryptofix (2,2,1) had a greater effect than 18-crown-6 at all pHvalues in this study. For 18-crown-6, retardation decreases in the order pH 9 > 4 > 7 while forkryptofix it follows the order pH 9 > 7 > 4.     

含羟基环多胺金属配合体系切割DNA及其体外抗肿瘤活性研究

研究了3-羟基-1,5,8-三氮杂环癸烷(L1)和3,13-二羟基-1,5,8,11,15,18-六氮杂二十元环胺(L2)与Ni(Ⅱ),Ca(Ⅱ),Co(Ⅱ),Cu(Ⅱ)离子在不同配比下与质粒pBR322DNA及肝癌细胞BEL-7402的相互作用情况.发现L1的单核体系和L2的双核体系能有效地将超螺旋DNA同时切割得到切口开环型和线型DNA,并对BEL-7402表现出明显的生长抑制作用.     

New Macrocyclic Diamides as Neutral Ionophores for Highly Selective and Sensitive PVC‐Membrane Electrodes for Be2+ Ion

Five recently synthesized macrocyclic diamides were investigated to characterize their ability as beryllium ion carriers in potentiometric PVC‐membrane electrodes. The electrodes based on 1,15‐diaza‐3,4;12,13‐dibenzo‐5,8,11‐trioxabicyclo[13,2,2] heptadecane‐2,14‐dione exhibited a Nernstian response for Be²⁺ ion over wide concentration ranges (from 3.0×10^?6 to 3.0×10^?2 M for polymeric membrane electrode, PME, and from 5.0×10^?7 to 2.0×10^?2 M for coated glassy carbon electrode, CGCE) and very low detection limits (2.0 ×10^?6 M for PME and 4.0×10^?7 M for (CGCE). The electrodes possess low resistances, fast responses, satisfactory reproducibilities and, most importantly, good selectivities relative to a variety of other common cations. The potentiometric response of the electrodes is independent of pH of test solution in the pH range of 4.0–7.5. The proposed sensors were used to determine beryllium ion in water samples.     

Applications of Macrocyclic Polyethers in Analytical Sensors and Ion Separation

Artificial macrocyclic polyethers were synthesized and applied as neutral carriers for ion-selective PVC membrane electrodes, ion-chromatographic packing materials, extractants and adsorbents for ion separation, coating materials for piezoeletrical membrane sensors for organic species, and ion-transport carriers through liquid membranes. Ion-selective electrodes such as those for K⁺ Na⁺, UO₂²⁺, Cs⁺, Pb²⁺, Fe³⁺, Hg²⁺ and Ag⁺ ions based on crown ether-phosphotungstic acid (PW) precipitates and dithio crown ethers respectively were prepared and showed good sensitivity and selectivity. Crown ether-PW precipitates were applied as adsorbents of rare-earth ions and some common heavy-metal ions. Some rare-earth ions were easily extracted with crown ethers, especially 15-crown-5. Poly(stytene/divinyl benzene) cryptand-22 resin was synthesized and applied as a bifunctional stationary phase of ion chromatography to separate bom cations and anions, even some organic carboxylate geometric isomers. Crown ethers such as mono-benzo-15-crown-5 was successfully applied as a coating material on piezoelectric quartz membrane sensors for some organic species. The oscillation frequency of the crown-ether quartz-membrane sensor was sensitive to organic vapours such as amines and alcohols. Upon adsorption of organic species on the crown-ether quartz membrane, the oscillation frequency of the sensor decreased obviously. Special crown ether such as dibenzo-16-crown-5-oxyacetic acid, decyl-cryptand-22 and 1, 4-dihydro-pyridine-18-crown-5 were synthesized and successfully applied as ion-transport carriers (ionophores) for transport of Na⁺ K⁺ and Mg²⁺ ions through liquid membranes.     

Selective Transport of Alkali—Metal Cations through Liquid Membranes by Non—Cyclic Carriers

The emission spectra of a series of naphthalene end-labeled oligo-oxyethylene(N-Pn-N) and their facilitated transport of cations across liquid membranes have been investigated.Alkali-metal cations enhance or inhibit the intramolecular excimer formation of N-Pn-N remarkably,suggesting that the polyether chain of N-Pn-N in solution complexes with the cations,and the orientation of the terminal chromophores depends on the cation size and the length of the polyether chain. These compounds are able to act as carriers to facilitate transport of alkali-metal cations through organic liquid membranes.The transport efficiencies are comparable with those of cyclic carriers such as crown ethers,and show remarkable selectivity.     

Studies on PNPP Hydrolysis Catalyzed by Divalent Metal Ion Macrocyclic Schiff Base Complexes in Micellar Solution

Two transitional metal ion macrocyclic Schiff base complexes, NiL and CuL were synthesized and characterized, and the metallomicelles made up of the nickel(II) and copper(II) complexes and surfactants(LSS, Brij35, CTAB), as mimic hydrolytic metalloenzyme, were used in catalytic hydrolysis of carboxylic ester (PNPP). The analysis of specific absorption spectrums of the hydrolytic reaction systems indicates that key intermediates, made up of PNPP and Ni(II) or Cu(II) complexes, have formed in the reaction processes of the PNPP catalytic hydrolysis. In this, based on the analytic result of specific absorption spectrum, the mechanism of PNPP catalytic hydrolysis has been proposed; a kinetic mathematical model, applied to the calculation of the kinetic parameter of PNPP catalytic hydrolysis has been established on the foundation of the mechanism proposed; the acid effect of reaction system, structure effect of the complexes, effect of temperature and effects of micelle on the rate of PNPP hydrolysis catalyzed by the complexes also have been discussed.     

大环手性磷酰胺对氨基酸衍生物的分子识别研究

以(S)-α-甲基苯乙胺和天然氨基酸(L-丙氨酸、L-苯甘氨酸及L-苯丙氨酸)为手性源,以2,5-二(邻羟基苯基)-1,3,4- 二唑和2,4-二(邻羟基苯基)-1,3,5- 二唑为刚性单元,合成了一系列具有光学活性的新型含 二唑磷酰胺和磷酯手性大环化合物.用NMR,IR和FABMS方法研究了所合成的手性大环对氨基酸甲酯盐酸盐和二肽的分子间相互作用和分子识别.结果表明,这些主体对D-或L-氨基酸甲酯盐酸盐和二肽具有选择性的结合作用.     

基于新型离子交换膜过程的含盐废水零排放技术

离子交换膜过程作为连续的离子交换过程,具有绿色、经济、可持续、无污染等优点。本文以近年来出现的新型离子交换膜过程的结构组成、分离机理等为出发点,结合含盐废水零排放过程面临的高能耗、易结垢、分盐难等关键问题,介绍了选择性电渗析、置换电渗析、反电渗析等新型离子交换膜过程在零排放领域的最新应用与研究进展;针对这些过程与其他分离技术的系统性集成操作进行了介绍与总结,并对其进行了初步分析和评述,以期为以后的研究工作提供参考。     

糖基修饰大环化合物的研究进展

糖类分子作为生命过程中多种特殊受体的底物,在生物信息传递中发挥着重要的作用.近年来,已通过各种方法高效率地制备了一些新型的糖基修饰的杯芳烃、环糊精和冠醚等大环分子,它们在生物凝集素特异性识别、选择性离子识别及手性催化等方面的应用引起了研究者的广泛兴趣.本文从糖基修饰大环分子的合成、功能化及其相关应用方面综述了目前糖基功...     

Novel Strategies for the Complexation of Neutral Guest Molecules by Synthetic Macrocyclic Hosts

Abstract

Complexes of macrocyclic polyethers with neutral guests have been studied in solution. The first part, a systematic study of complexes of malononitrile with a variety of macrocyclic polyethers, allowed the evaluation of the thermo-dynamic parameters of complexation. The second part deals with the complexation of urea. Complexes with simple 18-membered macrocycles were prepared. Protonation of urea allowed the phase transfer of urea from aqueous to chloroform solution. Finally the complexation of urea by 2-carboxy-1,3-xylyl crown ethers is described.     

Review of Selective Ion Separations at BYU Using Liquid Membrane and Solid Phase Extraction Procedures

Research in selective ion separations at Brigham Young University hasinvolved the use of liquid membranes of the bulk, emulsion, thin sheetsupported, hollow fiber supported, and two-module hollow fiber supportedtypes as well as solid phase extraction using immobilized ligands. By use ofdesigned cation and anion selective macrocyclic ligands, it has beenpossible to accomplish a wide range of interesting separations. Theprinciples underlying the separations and a comparison of the advantages anddisadvantages of the various systems are given. Some of the solid phaseextraction systems have been commercialized by IBC Advanced Technologies,Inc. Examples of commercial applications are presented in the analytical,environmental, metallurgical, precious metals, and nuclear waste areas.     

Kinetics of the Protonation of Macrocyclic Amines in the Presence of Monovalent Cations in Aqueous Solution

Abstract

For macrocyclic bases such as: 1-aza-15-crown-5 (N15C5),1,4,10-trioxa-7,13-diazacyclopentadecan (21), 1,7,10,16-tetraoxa-4,13-diazacyclooctadecan (22) and 1, 4, 7, 13, 16-pentaoxa-10, 19-diazacycloheneicosane (23), the kinetics of deprotonation and protonation reactions in the presence of monovalent cations was studied using the temperature jump technique. For the sake of comparison, the measurements were also performed for 1,4-diazabicyclo[2,2,2]octane (DABCO) base, which does not form complexes with monovalent cations. The monovalent cations affect the temperature dependence of the kinetic parameters of deprotonation. They also affect the activation parameters, which is shown by a distribution of ΔH≠ and ΔS≠ values, but do not influence the value of ΔG≠.