Immobilization of β-Cyclodextrin as Insoluble β-Cyclodextrin Polymer and Its Catalytic Performance

Insoluble β-cyclodextrin polymers were prepared from β-cyclodextrin(β-CD) using epichlorohydrin(EPI) as crosslinking agent under basic conditions.The polymers were characterized by Fourier Transform Infrared(FTIR),Thermogravimetry(TG),X-ray diffraction(XRD) and TG-FTIR.The results demonstrated that the polym-erization between EPI and β-CD indeed occurred,and a number of CD rings were interconnected to form a three-dimensional network.Moreover,different factors influencing the polymerization,e.g.molar ratio of EPI to β-CD,the concentration of NaOH and reaction temperature,have been investigated.The polymer prepared under the optimal conditions(the molar ratio EPI:β-CD of 44,the NaOH concentration 50% in mass,and the temperature at 65 ℃) showed excellent thermal stability and insolubility in organic solvents or strong acid/base.In addition,the β-cyclodextrin polymers also presented high catalytic activity for aqueous oxidation of benzyl alcohol with hy-pochlorite as oxidant.

Preparation of insoluble β-CD polymer and its application to enantiomers and isomers separation

An insoluble β-cyclodextrin polymer cross-linked with epichlorohydrin was prepared, and its structure was identified with infrared spectrum. Colloid stationary phase was prepared by dissolving the polymer in the mixed solvent of diisopropyl ether, methylene dichloride and benzene and treated for 0.5 h by ultrasonication, and then was coated on a fused silica capillary column. The optimun reaction conditions are as follows: the mole ratio of epichlohydrin to β-cyclodextrin is 12.1:1, reacting at 65 °C for 24 h. The Chromatographic performance such as column efficiency, thermal stabilities and polarity were studied, two kinds of disubstituted benzene isomers and eight pairs of enantiomers were separated on the capillary column. The results show that the β-cyclodextrin polymer is suitable for use as a capillary gas chromatographic stationary phase, and possess excellent chromatographic properties in separating enantiomers and position isomers.

Ionic liquids functionalized β-cyclodextrin polymer for separation/analysis of magnolol

Ionic liquids functionalized β-cyclodextrin polymer, a mono-6-deoxy-6-（1,2-dimethylimida- zolium）-β-cyclodextrin iodide polymer （ILs-β-CDCP）, was synthesized as a solid-phase adsorbent coupled with high-performance liquid chromatography for separating or analyzing magnolol in drug samples. The results showed that magnolol was adsorbed rapidly on ILs-D-CDCP and eluted with methanol. Under the optimum conditions, preconcentration factor of the proposed method was 12. The linear range, limit of detection （LOD）, correlation coefficient （R） and relative standard deviation （RSD） were found to be 0.02-8.00 μg/mL, 1.9 ng/mL, 0.9992 and 2.76% （n=3, c=2.00 pg/mL）, respectively. The interaction between 1Ls-]）-CDCP and magnolol was studied through the inclusion constant, FTIR and TGA analysis. This proposed method has been successfully applied to the determination of magnolol in real samples.

Efficient recovery of aromatic compounds from the wastewater of styrene monomer and propylene oxide co-production plant via hypercrosslinked aryl-rich starch-β-cyclodextrin polymeric sorbent

Adsorptive recovery of valuable components from industrial wastewater is highly desirable for avoiding resource wastage but remains a challenge.Herein,we develop an efficient continuous adsorption process for recovering aromatic compounds in wastewater from styrene monomer and propylene oxide coproduction(SMPO)plant.Based on our insight into the potential of bio-based porous materials for adsorption application,starch-graft-polystyrene(SPS)and aryl-modifiedβ-cyclodextrin(ACD)were prepared,and novel hypercrosslinked porous polymers combined SPS with ACD(HSPS-ACDs)were synthesized through external crosslinking approach.In a binary-component system,the best-performing one HSPS-ACD(H)with high ACD content and large specific surface area possessed superior capacities for the representative aromatic compounds,acetophenone(AP,2.81 mmol·g^(-1))and 1-phenylethanol(1-PE,1.35 mmol·g^(-1))compared with the previously reported materials.Further,the adsorption properties of aromatic compounds on HSPS-ACD(H)were investigated in batch mode.For practical application,continuous adsorption experiments were conducted in a HSPS-ACD(H)-packed fixed bed,where the target aromatic components in wastewater were effectively retained and further released by elution.Besides showing the reversible adsorption and efficient enrichment effect,the HSPS-ACD(H)-packed fixed bed also maintained great stability in multiple cycles.Moreover,quantum chemical calculations were performed to elucidate the potential mechanism of adsorption of AP and 1-PE onto HSPS-ACD(H).

Preparation of a novel biodegradable β-cyclodextrin-containing polymer

A novel cyclodextrin-containing polymer was prepared by graftingβ-cyclodextrin onto the backbone of poly(D,L-lactic acid)(PLA).First,mono(6-(2-aminoethyl)amino-6-deoxy)-β-cyclodextrin(β-CD-6-en)was prepared by sulfonylation and amination ofβ-cyclodextrin and modified poly(D,L-lactic acid)(MPLA)was prepared by free radical polymerization of maleic anhydride and PLA.Then,grafting ofβ-cyclodextrin derivative to MPLA backbone was carried out by N-acylation reaction of MPLA andβ-CD-6-en in dimethyl formamide.The...

STUDIES ON THE POLYMERIZATION OF β-CYCLODEXTRIN WITH EPICHLOROHYDRIN

Different proportions of β-cydodextrin and epichlorohydrin were used to prepare a group of β-cyclodextrin polymers. The relationship between the reaction extent and the molar ratios of reactants was discussed according to the results of ~1H-NMR, ^(13) C-NMR spectra and elemental analysis. Especially, high resolution ~1H-NMR spectra were usd for studying the reaction active sites and the extent of reaction. The solubility of oil soluble drugs in water was largely improved in the presence of water-soluble β-cyclodextrin polymer.

非水溶性钾矿制取碳酸钾:副产硅铝胶凝材料

白云鄂博稀土-铌-铁矿床上部围岩产富钾板岩,其K2O平均含量达13.0%,钾资源储量巨大.矿石的物相组成以微斜长石、黑云母为主,是一种重要的非水溶性钾矿资源.实验表明,以碳酸钠为助剂,经中温烧结,矿石分解率达98.2%以上.烧结物料中K2O的浸出率约70%,且在水浸酸化反应过程中,大部分Fe3+、Ti4+、Mn2+、Mg2+、Ca2+等杂质离子与硅铝质胶体同时沉淀析出,为制取电子级碳酸钾提供了可能.硅铝质胶体滤渣用于制备矿物聚合材料.采用本项技术开发利用此类非水溶性钾矿资源,符合节能高效和“清洁生产”的要求,兼有规模化经济效益和良好的环境效益.

水不溶性聚合物杀菌剂

综述了水不溶性聚合物杀菌剂 ,主要介绍了聚碘化合物杀菌剂、含氮水不溶性杀菌剂和含磷水不溶性杀菌剂 ,引用了近年来国内外研究人员在这方面的研究成果 ,也阐述了目前研制的产品仍存在的一些问题。聚碘化合物杀菌剂 ,具有杀菌谱广、效率高等优点 ,但它的余碘问题很难解决 ,尤其是在水中阴离子浓度较高或接触时间较长时更严重。目前研制较多的水不溶性含氮阳离子杀菌剂 ,一方面解决了现在普遍使用的水溶性杀菌剂的不足 ,另一方面还具有缓释、长效、可再生重复使用的优点 ,但杀菌活性和杀菌速率需进一步提高。含磷水不溶性杀菌剂 ,尤其是聚季 盐杀菌剂已显示出高效、快速和广谱的杀菌性能 ,但它们的制备条件苛刻 ,所制得的聚季 盐杀菌剂尚有一定水溶性需要解决。参考文献2

Eudragit L-100固定球毛壳霉菌木聚糖酶酶学性质的研究

采用可逆溶解性聚合物EudragitL-100对球毛壳菌木聚糖酶进行了吸附固定化。在1.0%EudragitL-100浓度时获得10.6IU/mg载体的固定化酶活和88.47%的酶活回收。酶固定化后最适温度不变,最适pH向碱性方向移动了一个pH单位。固定化酶热稳定性和操作稳定性显著提高,循环利用6次仍保留65%初始酶活。木聚糖水解产物测定表明,在同酶用量的条件下固定化后总还原糖产量明显高于游离酶,二者水解产物均以低聚糖为主,酶固定化后水解产物木二糖含量显著高于游离酶,成为主要的产物。木聚糖酶固定化后各方面特性明显优于游离酶,在低聚糖生产中有实际应用价值。

非水溶性的β-环糊精聚合物的主客体包合作用及在过氧化氢生物传感器中的应用

非水溶性的β-环糊精交联聚合物(β-CDP)与戊二醛缩聚生成的聚合物带有悬挂的羰基,使辣根过氧化酶共价固定化;β-CDP与介体甲苯胺兰(TB)发生主客体包合作用将介体固定在电极表面,既避免了介体的流失又保证了介体有充分的流动性,实现了介体和酶的同时固定化。由于包络物的形成,使得H_2O_2生物传感器有较好的稳定性及较高的灵敏度,其线性相应范围为5.0μmol/L～10mmol/L,检测限为1μmol/L,达95％稳态响应电流所用时间少于30s。

TDI交联β-环糊精聚合物的制备及其催化氧化肉桂醛

以β-环糊精(-βCD)为原料,通过调整交联剂甲苯-2,4-二异氰酸酯(TD I)用量,合成了亲水性能理想的不溶性β-环糊精聚合物(β-CDP)。利用红外光谱仪、X射线衍射仪、综合热分析仪进行了表征,同时对溶解度和溶胀能力进行了测定。结果表明,TD I与-βCD发生交联后,生成的聚合物保留了β-CD的空腔结构,分解温度提高至350℃。同时,该聚合物在常见溶剂中的溶解度低于0.1%,在水中的溶胀能力仅为0.4 mL/g,说明产物在热稳定性、化学稳定性和机械强度等方面均得到了提高。最后,将该聚合物用于肉桂醛氧化生成苯甲醛的反应,催化效果明显,苯甲醛的收率提高至48%,且可重复使用。说明该聚合物不仅保留了-βCD的包结催化性能,并且能够稳定地用于水相有机反应中。

Supramolecular complex formation of β-cyclodextrin polymer with substituted salicylic acid or 3-hydroxy-2-naphthoic acid and their electrorheological behaviors

According to the chemical design, electrorheological properties of supramolecular complex from β-cyclodextrin polymer (β -CDP) were discussed. Six supramolecular complexes of β-cyclodextrin polymer with substituted salicylic acid and 3-hydroxy-2-naphthoic acid were synthesized by the solid-phase self-assembly method, and their component and structure were characterized by NMR, FT-IR, UV-vis and the fluorescence analysis. Then the electrorheological properties of their suspensions in silicone oil were investigated under DC electric fields. It was found that the yield stresses of these supramolecular complex ER fluids were 7.3–9.8 kPa at 4 kV/mm in DC electric field, which were enhanced by 34%–72% compared with that of pure β-CDP. Among them, that of β-CDP/3-hydroxy-2-naphthoic acid ER fluid was the highest. It was also found that the ER effect of supramolecular complexes can be controlled by changing different guests. When the substituted group is at phenyl ring, ER behavior can be slightly adjusted by the different substituted groups, their number as well as their position at phenyl ring. This can be proved by the measurement of dielectric properties.

Preparation and characterization of cross-linked β-cyclodextrin polymer/Fe_3O_4 composite nanoparticles with core-shell structures

Cross-linkedβ-cyclodextrin polymer/Fe3O4 composite nanoparticles with core-shell structures were prepared via cross linking reaction on the surface of carboxymethylβ-cyclodextrin（CM-β-CD） modified Fe3O4 nanoparticles inβ-cyclodextrin alkaline solution by using epichlorohydrin as crosslinking agent.The morphology,structure and magnetic properties of the prepared composite nanoparticles were investigated by transmission electron microscopy（TEM）,Fourier transform infrared（FTIR） spectrometry,X-ray diffraction（XRD） measurement,thermogravimetric analysis（TGA） and Vibrating sample magnetometry （VSM）,respectively.

β-Cyclodextrin polymer networks stabilized gold nanoparticle with superior catalytic activities

Support materials play a significant role in heterogeneous nanocatalysis.In this work,β-cyclodextrin(β-CD)was used directly as a monomer to construct polymer networks for gold nanoparticles(Au NPs)immobilization.Using the simple nucleophilic substitution reaction,β-CD based polymer networks(β-CDP-N andβ-CDP-C)were successfully prepared.Compared toβ-CDP-C,the hydroxyl groups and N atoms inβ-CDP-N played a synergistic role in immobilizing smaller Au NPs,thus leading to high catalytic activities.Notably,the apparent rate constant(Kapp)value for Au@β-CDP-N in the reduction of 4-nitrophenol to 4-aminophenol is 14.15×10^(-2)s^(-1),which shows a significant improvement over all previously reported Au NPs with solid supports under similar conditions.Considering the negligible porosity of theβ-CDP-N support,we purposed a"capture-catalysis-release"model to explain the high catalytic activity of Au@β-CDP-N.This explanation is supported by the guest-responsive properties ofβ-CDP-N.Moreover,the Au@β-CDP-N is easily recycled and maintained its high catalytic efficiency after seven successful cycles.

Study on the Synthesis and Characterization of Novel Immobilized β-Cyclodextrin Polymer (Ⅰ)

<正> A series of novel β-cyclodextrin polymers was synthesized by immobilization of β-cyclodextrin on the chloromethylated crosslinked polystyrene carriers. The synthetic conditions such as reaction time, temperature, molar feeding ratio of reactants, the degree of crosslinking of polystyrene and the catalysts used were studied in detail and the chemical and physical structures of the formed β-CDpolymers were characterized. Results show that the preparation method is simple and the amount of β-CD immobilized is high. As biomedical adsorbents, they were tested for removal of various endogenous and exogenous toxins such as phenols, aromatic amins, barbitals and unconjugated bilirubin. Results indicate that the adsorptión capacity for those toxins can be enhanced by the inclusion interaction among the β-CD, the substrate molecules and the β-CD polymers.

Recent progress in encapsulation and controlled release of pesticides based on cyclodextrin derivative carriers

In the context of the continuous increase in global grain production,accompanied by a large amount of investment in various pesticides,herbicides,fungicides,and other chemical pesticides.It has caused inevitable environmental problems and food safety problems.Current research suggests that the use of cyclodextrins and their derivatives to protect pesticides can significantly reduce the number of agrochemicals that pollute the environment.Using the cavity properties of cyclodextrins,we can refer to the similar way in which drug molecules make cyclodextrins and cyclodextrin polymers to form inclusion compounds.Overall,β-cyclodextrin and its derivatives are used as a new pesticide excipient to improve the stability of pesticides,prevent their oxidation and decomposition,improve the solubility and bioavailability of pesticides,reduce the toxic side effects of drugs,and mask the odour of drugs.In this review,we focus on summarising the recent research progress ofβ-cyclodextrins and their derivatives in pesticides and other fields,and provide a systematic classification ofβ-cyclodextrin polymers,as well as new synthesis methods and techniques in various applications.Finally,the future development of cyclodextrin-like polymers is foreseen,and issues arising from the research are discussed and addressed in depth.

β-Cyclodextrin polymer based fluorescence enhancement method for sensitive adenosine triphosphate detection

Adenosine triphosphate plays a crucial role in regulation of many biological pathways and has been used as an indicator for many diseases.In this pape r,based on the fact that β-cyclodextrin polymer(polyβ-CD)could significantly enhance pyrene fluorescence through supramolecular assembly(host-gest interaction),a sensitive and facile method for adenosine triphosphate detection has been developed.A 3’-pyrene-labelled ATP-binding aptamer was employed as the fluorescence probe,which could be digested by exonuclease I to obtain mononucleotides,with pyrene attached on.The pyrene attached on mononucleotides could easily enter the hydrophobic cavity of polyβ-CD,accompanied with prominent fluo rescence enhancement.While ATP was introduced,ATP and its aptamer could combine together and the obtained hairpin complex could not be cleaved by exonuclease Ⅰ,The pyrene labelled on the probe could not enter the cavity of polyβ-CD belong to the complex’steric hindrance,accompanied with the weak pyrene’fluorescence.So we could quantify the concentration of adenosine triphosphate facilely by measuring the fluorescence intensity of the system.The detection limit of this method for adenosine triphosphate was 11 μmol/L(S/N=3),The developed method showed sufficient selectivity and could successfully assay adenosine triphosphate in biological samples.The developed method provides a potential platform for biological micromoles assay.

A simple and sensitive assay for apurinic/apyrimidinic endonuclease 1activity based on host-guest interaction of β-cyclodextrin polymer and pyrene

Apurinic/apyrimidinic endonuclease 1（APE1） plays an important role in protecting the fidelity of genetic material and is also a promising biomarker of cancers. Herein, a simple and sensitive fluorescent method for APE1 activity detection was designed based on host-guest interaction between β-cyclodextrin polymer（β-CDP） and pyrene. In this method, pyrene-labelled DNA probes（AP-S1 S2） and β-CDP functioned as fluorescent signal producer and enhancer, respectively. When APE1 was absent, pyrene on the AP-S1 S2 could not enter the cavity of β-CDP because of steric hindrance, leading to a weak fluorescence intensity/anisotropy. When APE1 was present, it would recognize and cleave AP site in APS1 S2, thus producing a dissociated pyrene-labelled oligonucleotide segment. Pyrene labelled at the 50 end of oligonucleotide segment could be easily trapped into the cavity of β-CDP via host-guest interaction, leading to a significant enhancement of fluorescence intensity/anisotropy. This assay offered a dynamic range of 0.05 U/m L–5 U/m L and an estimated detection limit of 0.05 U/m L. Furthermore,assessment of APE1 activity in He La cell extracts was successfully implemented, which hold the potential for APE1-related cancer diagnosis and biological researches.

影响聚合物产品不溶物指标因素的分析及控制措施

聚合物生产工艺中聚合反应的好坏直接影响到产品的粘度,如果粘度偏低,则达不到分子量指标;若粘度偏高,则易使水解后的产物不溶物指标偏高甚至超标。影响聚合反应的因素有流量计准确性;吹氮过程中氮气含氧量;催化剂加入量;熟化时间;反应胶体造粒的大小和PH值等影响因素。控制措施包括减少杂质含量,控制PH值范围,优化聚合操作等。

β-cyclodextrin assists salt-resistance polymer flooding:Injectivity improvement

Polymer flooding method has attracted wide attentions in petroleum industry because of its relatively simple process equipment,low cost of agents and good performance on enhancing oil recovery.However,common polymer can hardly meet the technical requirements of the oilfields with high salinity.Existing salt-resistance polymer solutions get a large viscosity in high salinity condition by changing polymer molecules aggregation which,however,may result in the poor adaptability between polymer molecules and the pore sizes of reservoir.β-cyclodextrin(β-CD),a kind of chemical agent,is found to enhance the injectivity of salt-resistance polymer solutions by wrapping the hydrophobic groupings of salt-resistance polymer molecules.For a certain reservoir,the addition ofβ-cyclodextrin into salt-resistance polymer solution can balance the effect of plugging the layers with high permeability and the purpose of diverting to the layers with low and medium permeability.In this paper,viscosity of polymer solution is tested in condition of different concentrations ofβ-CD.On that basis,experiments on seepage characteristics are carried out to evaluate the injectivity of salt-resistance polymer solution.Finally,an appropriate concentration ofβ-CD,which is added into salt-resistance polymer solution,is chosen to adapt a certain reservoir with heterogeneity.