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 mixe...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 ℃ 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.展开更多
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-perform...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.展开更多
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 recoveri...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).展开更多
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 accord...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.展开更多
Enantiomer of (-pyrrolidinyl phenylpropanol was studied by capillary electrophoresis using (-cyclodextrin polymer as chiral selector. We determined the enantiomeric excess value of (-pyrrolidinyl phenylpropanol with R...Enantiomer of (-pyrrolidinyl phenylpropanol was studied by capillary electrophoresis using (-cyclodextrin polymer as chiral selector. We determined the enantiomeric excess value of (-pyrrolidinyl phenylpropanol with RSD 0.48%.展开更多
According to the chemical design, electrorheological properties of supramolecular complex from b-cyclodextrin polymer (b -CDP) were discussed. Six supramolecular complexes of -cyclodextrin polymer with substituted sal...According to the chemical design, electrorheological properties of supramolecular complex from b-cyclodextrin polymer (b -CDP) were discussed. Six supramolecular complexes of -cyclodextrin polymer with substituted salicylic acid and 3-hydroxy-2-naphthoic acid were syn-thesized 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 b-CDP. Among them, that of b-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 dif-ferent 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.展开更多
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 nanoparti...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.展开更多
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.Usi...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.展开更多
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, mo...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.展开更多
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 s...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.展开更多
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 A...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.展开更多
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 c...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.展开更多
A one-step and facile strategy toward the construction of multicolor polymers via supramolecular selfassembly was proposed.Multicolor polymers were simply prepared by the self-assembly of adamantane-labeled fluorescei...A one-step and facile strategy toward the construction of multicolor polymers via supramolecular selfassembly was proposed.Multicolor polymers were simply prepared by the self-assembly of adamantane-labeled fluorescein,adamantane-labeled rhodamine B and β-cyclodextrin polymers via host-guest interaction between β-cyclodextrin and adamantane.Multicolor polymers showed several interesting properties:multiple emission signatures by a single wavelength excitation,easy tunability,intense fluorescence,high photostablility.In addition,the self-assembly approach implied a facile and flexible strategy for constructing functionalized materials,such as multicolor materials for biological labeling and imaging,and sensing materials for the detection of physiological parameters.展开更多
文摘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 ℃ 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.
基金the financial support from the National Natural Science Foundation of China(Nos.21155001 and 21375117)a project funded by the Priority Academic ProgramDevelopment of Jiangsu Higher Education Institutionsthe Foundation of the Excellence Science and Technology Invention Team in Yangzhou University
文摘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.
基金supported by National Natural Science Foundation of China(21868002 and 21961160741)the Natural Science Foundation of Guangxi Province(2018GXNSFAA281206,2020GXNSFGA297001,2020GXNSFAA297044)+2 种基金Dean Project of Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology(2021Z010)Specific research project of Guangxi for research bases and talents(AD18126005)special funding for‘Guangxi Bagui Scholars’,Guangxi scholarship fund for the middle-aged backbone teachers。
文摘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).
基金The project is supported by National Natural Science Foundation of China
文摘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.
文摘Enantiomer of (-pyrrolidinyl phenylpropanol was studied by capillary electrophoresis using (-cyclodextrin polymer as chiral selector. We determined the enantiomeric excess value of (-pyrrolidinyl phenylpropanol with RSD 0.48%.
基金This work was supported by the National Namral Science Foundation of China(Grant No.59832090)the National Natural Science Foundation of China for Distinguished Young Scholar(Grant No.50025207)the'863'Foundation(Grant No.2001AA327130).
文摘According to the chemical design, electrorheological properties of supramolecular complex from b-cyclodextrin polymer (b -CDP) were discussed. Six supramolecular complexes of -cyclodextrin polymer with substituted salicylic acid and 3-hydroxy-2-naphthoic acid were syn-thesized 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 b-CDP. Among them, that of b-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 dif-ferent 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.
基金financially supported by the Guangdong Natural Science Foundation(No.020891)
文摘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.
基金the National Natural Science Foundation of China(Nos.21865003,21562003)China Postdoctoral Science Foundation(No.2018M640114)+1 种基金National Undergraduate Training Programs for Innovation and Entrepreneurship(No.201910418003)the Gannan Normal University Innovation Fund(No.YCX19A002)for generous support.
文摘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.
文摘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.
基金financially supported by the National Natural Science Foundation of China (Nos. 21305002 and 21705002)the Scientific Research Foundation of Anhui Agricultural University (No. yj2017-19)
文摘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.
基金supported by the National Natural Science Foundation of China (Nos. 21675047, 21375034, 21190040)the Foundation for Innovative Research Groups of National Natural Science Foundation of China (No. 21521063)
文摘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.
文摘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.
基金supported by the National Natural Science Foundation of China(Nos.21190044,21175035)National Basic Research Program(No.2011CB911002)International Science & Technology operation Program of China(No.2010DFB30300)
文摘A one-step and facile strategy toward the construction of multicolor polymers via supramolecular selfassembly was proposed.Multicolor polymers were simply prepared by the self-assembly of adamantane-labeled fluorescein,adamantane-labeled rhodamine B and β-cyclodextrin polymers via host-guest interaction between β-cyclodextrin and adamantane.Multicolor polymers showed several interesting properties:multiple emission signatures by a single wavelength excitation,easy tunability,intense fluorescence,high photostablility.In addition,the self-assembly approach implied a facile and flexible strategy for constructing functionalized materials,such as multicolor materials for biological labeling and imaging,and sensing materials for the detection of physiological parameters.