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Table of Content

    10 January 2008, Volume 29 Issue 1
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    综合评述
    Review and Progress in the Study of Mesongen-Jacketed Liquid Crystalline Polymer
    CHEN Xiao-Fang, FAN Xing-He, WAN Xin-Hua, ZHOU Qi-Feng*
    2008, 29(1):  1-12.  doi:
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    Progress in the study of molecular structure and property relationship of mesogen-jacketed liquid crystalline polymers(MJLCPs) was reviewed. Different from traditional side chain liquid crystalline polymers, MJLCPs have semirigid polymer chain conformation due to the strong interaction between the side chain mesogens and the polymer backbone. Supramolecular liquid crystalline columnar phases are thus formed in most of MJLCPs systems. The self-assembly behavior of the block copolymers containing MJLCPs as rod segments have been studied as well both in melt and in solutions. Lamellar and perforated lamellar microphase separated structures could be found in diblock copolymers, while in solutions micelles with MJLCP core surrounded by the coil corolla were easily formed. Meanwhile, MJLCPs and the related block copolymers could be exploited as the functional materials with unique electro-optical properties. An outlook for the future development in this area is proposed in the last part of this review.
    研究论文
    Preparation and Characterization of Ordered Mesoporous Alumina with High Specific Surface Area with F127 as Template
    LI Zhi-Ping1, ZHAO Rui-Hong2, GUO Fen1*, CHEN Jian-Feng1, WANG Gang1
    2008, 29(1):  13-17.  doi:
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    Ordered mesoporous alumina was synthesized by sol-gel method with isopropoxide alumina as the source of alumina and PEO-PPO-PEO block copolymer F127 as the template. The results show that the mesoporous alumina surface area(480 m2/g), narrow pore size distribution(2—20 nm), and lange pore volume(over 1.2 cm3/g). Worm-like pore was formed and ordered to some extent. The structure of the synthesized sample was investigated by BET, TEM, and XRD technologies. The influence of various conditions on the structure of ordered mesoporous alumina was discussed.
    Synthesis of Nickel Hydroxide Flower-like Microspheres by Template-free Liquid Process
    WANG Ru-Na, LI Qun-Yan*, WANG Zhi-Hong, WEI Qi, NIE Zuo-Ren
    2008, 29(1):  18-22.  doi:
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    Flower-like Ni(OH)2 microspheres were successfully synthesized with a facile template-free liquid process with hydrofluoric acid solution as the nickel ion ligand to form nickel-fluoro complex, NH3 aqueous solution as the OH- supplier and supplemental nickel ion ligand. The flower-like Ni(OH)2 microspheres were composed of dozens of nanoflakes with α-Ni(OH)2 and β-Ni(OH)2 mixed crystallinity. Morphologies of the Ni(OH)2 microspheres are influenced greatly by Ni(Ⅱ) concentrations while other solution conditions are fixed. When Ni(Ⅱ) concentration is 0.03 mol/L, the uniform flower-like Ni(OH)2 microspheres with average diameters of about 2 μm were obtained and composed of nanoflakes with length of about 400 nm and thickness of about 60 nm. The formation mechanism from aggregation growth and surface growth to surface dissolution was proposed, which was in good agreement with observation on the Ni(OH)2 samples during the reaction process.
    Size-controlled Synthesis, Characterization and Microwave Absorption Efficiency of Fe3O4 Nanocrystallines
    YAN Ai-Guo, QIU Guan-Zhou, LIU Xiao-He*, SHI Rong-Rong, ZHANG Ning, YI Ran, LI Yong-Bo, GAO Guan-Hua
    2008, 29(1):  23-27.  doi:
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    Fe3O4 nanocrystallines were successfully prepared by using the mixed surfactants of SDS and PEG as the protective reagents. The sizes of the nanoparticles can be varied from 10 to 200 nm by adjusting the experimental conditions. The microstructure, size and morphology of the products were investigated in detail by X-ray diffraction(XRD), transmission electron microscopy(TEM), and scanning electron microscopy(SEM). The results indicate that uniform spinel Fe3O4 nanospheres were achieved. Magnetic studies on the samples with different sizes reveal that when the size of product is below 80 nm, the saturation magnetization(Ms) increases as the particle size increases, where the coercive force (Hc) decreases as the particle size decreases. Both of electromagnetic performance and microwave adsorption property of Fe3O4 nanocrystallines with different sizes were measured by a vector network analyzer(VNA) technique in the frequency region of 2—18 GHz. The results indicate that when the sizes of the samples are below 100 nm, Fe3O4 nanocrystallines exhibit a better microwave adsorption property. For example, the reflection loss is up to 32 dB for the sample with the nanoparticle size of 20 nm.
    Controlled-synthesis of ZnO Nanorings
    PENG Yin*, BAO Ling
    2008, 29(1):  28-32.  doi:
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    ZnO nanorings were prepared on a large scale by a facile solution-based method at 70 ℃ for 5 h via hexamethylenetetramine(C6H12N4) and Zn(NO3)2·2H2O as the raw materials in the presence of surfactant PAM-CTAC. The structure and morphology of as-prepared products were characterized by X-ray powder diffraction(XRD) and scanning electron microscopy(SEM). The studies of the influences of experimental conditions such as concentration of surfactant and reactants, reactive temperature and time on the structure and morphology of as-prepared products were carried out. Probable formation mechanism of ZnO nanoring in the presence of surfactant PAM-CTAC was discussed. The results show that as-prepared products are wurtzite hexagonal structure ZnO nanorings with the inner diameter of 220 nm and the wall thickness of nanoring of 70 nm. Reaction temperature and concentration of reactants have influence on the formation and size of ZnO nanorings, but the surfactant PAM-CTAC plays the key role in the formation of ZnO nanorings. Through adjusting the concentration of PAM-CTAC, ZnO nanorings can be synthesized under control. A room temperature FL spectrum of ZnO samples shows that the full width at half maximum(FWHM)(~7 nm) of the UV emission is much narrower than that of commercial ZnO bulk crystals(~18 nm), the narrow FWHM confirms the uniformity and narrow size distribution of the as-synthesized ZnO crystals.
    Hydrothermal Synthesis and Crystal Structure of Cluster Compound {[Ni(enMe)2][SiW12O40]}[Ni(enMe)2(H2O)2]2·3H2O
    YANG Xiao-Gang1,2, LIU Zhi3, YU Qing1,2, WANG Ben4, HOU Bao-Rong1*
    2008, 29(1):  33-36.  doi:
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    The novel One-dimensional chain structure of the title cluster compound was synthesized and characterized by elemental analysis, IR spectra, TGA and X-ray single-crystal diffraction. The title cluster compound crystallized in a monoclinic system with space group C2/c, a=1.2656 nm, b=2.20656(4) nm, c=2.26763(4) nm, β= 92.078°, V=6.32852(16) nm3, Z=4, Dc= 3.801 g/cm3, μ=2.271 mm-1, F(000)=6512, R1=0.0549, wR2=0.1087. The structure building block of the structure is the polyanion [SiW12O40]6- with α-Keggin structure. The clusters were linked together with one-dimensional infinite chain through [Ni(enMe)2]2+ cations. The [Ni(enMe)2(H2O)2]2+ cations and water molecules were filled in the structure. The cluster compound was expanded to three-dimensional framework by hydrogen bond interactions among molecules.
    Novel Fluorescent Method of Protein Detection Using Hairpin Nucleic Acid Aptamer Based on Polymerase Reaction
    GUO Qiu-Ping, YANG Xiao-Hai, WANG Ke-Min*, MENG Xiang-Xian, LI Jun, TAN Wei-Hong
    2008, 29(1):  37-40.  doi:
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    Aptamers are a new class of oligonucleotides generated from in vitro selection with a high affinity and specificity to targets. In this paper, a novel fluorescent method of protein detection was developed via hairpin aptamer based on polymerase reaction. The hairpin aptamer was designed as protein ligand and template of the polymerase reaction. When the aptamer was bound to the target protein, it would change to a linear strand and induce the polymerase reaction. Then protein detection was carried out by monitoring the polymerase reaction without directly labeling with the aptamer, with a linear range of 0.5—8 nmol/L and detection limit of 0.5 nmol/L. This proposed method has a potential advantage to design other protein probe with linear aptamer with a complex structure and can be used as a simple and general tool for protein detection.
    Proteomics Comparative Analysis of Thermo-sensitive Genic Male-sterile
    Rice Zhu-1S and Its Dwarfing Variant SV14 Stem
    XIAO Xiao-Juan1, YANG Yuan-Zhu2, LIN Jian-Zhong1, TONG Chun-Yi1,
    YANG Yue-Jun1, HUANG Lü-Hong1, LI Yan1, LIU Xuan-Ming1*
    2008, 29(1):  41-45.  doi:
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    The stem of thermo-sensitive genic male-sterile rice Zhu-1S and its dwarfing variant SV14 were separated by 2-DE. Twelve differential spots were identified by MALDI-TOF-MS.In the 2-DE protein patterns of SV14, one up-regulated proteins and eleven down-regulated proteins were identified. According to the functional classification of identified proteins, they were divided into the following categories: (1) energy metabolism; (2) secondary metabolism; (3) regulatory proteins; (4) proteins with unknown function. Furthermore, semi-quantitative RT-PCR was carried out to verify the different expressions. These results shows converse changes in expression at both the RNA and protein levels. The converse changes suggest that during the process of stem development some kind of post-transcriptional modification of these genes occurred. The results show that these proteins may be related to dwarfing rice stem and provide another pathway for finding the dwarfing gene.
    Preparation and Characterization of Hydrophilic Quantum Dot-tagged Nanoparticles and Their Application in Biodetection
    LI De-Na1, ZHANG Bing-Bo1, MA Gui-Ping2, LIU Xu-Hui2, TIAN Hui1, ZHANG Tai-Ping1, CHANG Jin1*
    2008, 29(1):  46-49.  doi:
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    Hydrophilic nanoparticles for biological assay were prepared by encapsulating luminescent quantum dots into an amphiphilic polymer via the method of ultrasonic emulsification(O/W). The samples were characterized via photoluminescence(PL) and transmission electron microscope(TEM). The results indicated that the method was simple, time/energy-saving and environmentally friendly. QDs-tagged nanoparticles obtained by this procedure were water-soluble, highly stable and bright in fluorescence emission with a size of 70 nm. After being water-solubilized by amphiphilic polymer, the QDs were labeled by IgGs and used in the biodetection. Spectral analysis showed that on FRET appeared in the water-soluble QDs modified by amphiphilic polymer. The immunofluorescence in vitro indicated that the QDs-IgGs bioconjugates had excellent specific bingding detection ability with nearly non-specific binding. On the basis of the properties QDs-tagged nanoparticles may have great potential for biodetection.
    Novel Surface-enhanced Resonance Raman Scattering Probe for Nitric Oxide
    LUO Chun-Hua, WU Zhao-Yang*, SHEN Guo-Li, YU Ru-Qin
    2008, 29(1):  50-54.  doi:
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    A novel diamino-azobenzene dye was designed and synthesized as a Raman indicator for NO. The Raman chemical transformation of the diamino-azobenzene structure is based on the reactivity of diamines with NO in the presence of dioxygen. The N-nitrosation of the diamino-azobenzene, yielding the benzotriazole-based compounds which exhibit a strong propensity to bind to Ag nanoparticles, offers a simple protocol for the direct detection of NO. As the addition of NO, the SERS spectra of the system changed evidently in the range of 1200—1700 nm and turned out a strong SERS peak at 1300 nm. The effects of the concentration of the dye, the aggregation of the nanoparticles and the pH of the solution were evaluated in detail. The result shows that the detection limit of the SERS probe reaches 10-8 mol/L and the system is independent of pH in the range of 4.5—7.5.
    Studies on the Biotransformation of Aconitine in Human Intestinal Bacteria Using Soft-ionization Mass Spectrometry
    ZHAO Yu-Feng1,2, SONG Feng-Rui1, GUO Xin-Hua1, LIU Shu-Ying1*
    2008, 29(1):  55-59.  doi:
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    To study the biotransformation of aconitine in human intestine, aconitine was incubated with human intestinal bacteria in vitro. Aconitine and its metabolites formed the protonated molecule [M+H]+ in positive ion mode. According to the m/z of [M+H]+, the metabolites of aconitine were investigated by electrospray ionization tandem mass spectrometry directly. Aconitine can be transformed by human intestinal bacteria. Aconitine was converted into more than twenty kinds of new metabolites such as mono-ester aconitum alkaloids, diester aconitines and lipo-alkaloids by deacetylation, dehydroxylation, demethylation and esterification.
    Determination of Toluidine Blue by Combination of Surface Plasmon Resonance with Cyclic Voltammetry
    CHEN Shou-Hui1, NI Yong-Nian1*, YANG Fan2, YANG Xiu-Rong2
    2008, 29(1):  60-63.  doi:
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    A method based on the combination of surface plasmon resonance(SPR) with cyclic voltammetry(CV) with the aid of wavelet transform technique was established for the detection of toluidine blue. The gold film of the sensor chip was used as both the generator of SPR measurement and the work electrode of electrochemistry analysis, Ag/AgCl electrode as the reference electrode, and the Pt electrode as the counter electrode. The scans of SPR and CV were performed simultaneously. The results show that due to electro-chemical polymerization of toluidine blue, the potential of oxidation peak shifted positively, the potential of reduction peak remained constant, and the response of SPR fell totally. The results obtained by taking derivative on the SPR response were processed by wavelet transform, and it was found that the response increased linearly with the concentration in range of 8.18—16.35 mmol/L for toluidine blue, with the limit of detection(LOD) of 4.01 mmol/L. Both the linear range and the LOD obtained by the proposed method compare well with the figures of merit given by the CV.
    Preparation of Bovine Hemoglobin-imprinted Polymer Beads via Photografting Surface-Modified Method
    GAI Qing-Qing1,3, LIU Qiu-Ye1, LI Wen-You1, HE Xi-Wen1*, CHEN Lang-Xing1, ZHANG Yu-Kui1,2*
    2008, 29(1):  64-70.  doi:
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    Molecularly imprinted polymers(MIP) based on photografting surface-modified polystyrene beads as matrices were prepared with acrylamide as the functional monomer, bovine hemoglobin as the template molecule and N,N′-methylene bisacrylamide as the crosslinker in a phosphate buffer. The results of IR, scanning electron microscope(SEM) and elemental analysis demonstrate the formation of a grafting polymer layer on the polystyrene-bead surface. Subsequent removal of the template leaves behind cavities on the surface of polymer matrix with a shape and an arrangement of functional groups in complementary binding sites to the original template. And the adsorption studies show that the imprinted polymers have a good adsorption capacity and specific recognition for bovine hemoglobin as the template molecule. Our results demonstrated that the polymer prepared via photografting surface-modified method exhibited a better selectivity for the template. Attempt to employ the new method in molecular imprinting techniques may indroduce new application to MIPs and facilicate the probable protein separation and purification.
    Determination of Honokiol and Magnolol in Both Human Plasma and Complex Magnoliae Officinalis by Second-order Calibration Coupled to Three-dimensional Excitation-emission Fluorescence Spectra
    JIANG Jun-Duo, WU Hai-Long*, XIA A-Lin, ZHU Shao-Hua, LIU Di-Si, ZHANG Hui-Feng, YU Ru-Qin
    2008, 29(1):  71-76.  doi:
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    A simple method, second-order calibration coupled to three-dimensional excitation-emission fluorescence spectroscopy, was described for the direct determination of honokiol and magnolol in human plasma and complicated magnoliae officinalis. When the component number(N) was set to 3, the obtained recoveries of honokiol and magnolol in human plasma by using the parallel factor analysis(PARAFAC) were (99.5±2.6)% and (90.2±1.8)%, respectively. As the alternating trilinear decomposition(ATLD) was utilized, the recoveries of honokiol and magnolol were (104.2±3.2)% and (98.7±4.0)% for N=3, (102.7±2.9)% and (99.0 4.6)% for N=4, respectively. And the method was used to determine honokiol and magnolol in complex magnoliae officinalis, the obtained results were also satisfactory. It was shown that the proposed method can be used to determine directly honokiol and magnolol, even in the presence of unknown interferences, with a simple pretreatment procedure.
    Selenium Speciation in Enriched Laminaria Japonica by HPLC-ICP-MS
    ZHONG Na1,2, WANG Xiao-Ru3*, YANG Huang-Hao3, CAO Xuan1, WANG Geng4
    2008, 29(1):  77-80.  doi:
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    In the present study, the concentration and speciation of selenium in Laminaria, enriched with selenite during its growth, was performed by establishing a RP-HPLC-ICP-MS method to separate selenite, MeSeCys and SeMet successively. There were three of systems ion-pairing agent and buffer chromatograph: (1) Alltima C8 column, mobile phase: 5 mmol/L citric, 5 mmol/L hexanesulfonic acid(pH 3.5)-methonol(95∶5, volume ratio); (2) Alltima C8 column, mobile phase: water-methnol(98∶2, volume ratio)-0.1%TFA; (3) Alltima C18 column, mobile phase: 20 mmol/L ammonium acetic-methonol(95∶5, volume ratio).Three solvent of 0.1 mol/L HCl, 20 mmol/L Tris-HCl and 20 mmol/L ammonium acetic buffer were used for the extraction of seleno-compound from enriched Laminaria, the major selenospecies determined were selenite, MeSeCys, SeMet, compared with the relative retention time of Se standards.
    研究快报
    Sensitive Determination of Norepinephrine by Capillary Electrophoresis with Indirect Electrochemiluminescence Detection and Its Application to Analysis of Human Urine
    LIU Yan-Ming*, CAO Jun-Tao, ZHENG Yan-Li
    2008, 29(1):  81-82.  doi:
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    A new method for sensitive and rapid indirect electrochemiluminescence(IECL) detection of norepinephrine(NE), synephrine, and isoproterenol with capillary electrophoresis(CE) was developed. IECL detection is based on their quenching effects on Ru(bpy)32+/tripropylamine(TPA) system. Under the optimum conditions, the detection limits(S/N=3) were 2.6×10-8 mol/L for NE, 6.6×10-9 mol/L for synephrine, and 8.4×10-8 mol/L for isoproterenol. The RSD of migration time and peak area were less than 1.3% and 4.4%, respectively. The proposed method was successfully applied to the analysis of NE in the urine samples of 10 healthy people and 10 diabetic nephropathy patients. The results indicate that the content of NE in diabetic nephropathy patients is much higher than that in healthy people.
    Synthesis of Fluorescent Nanoparticle Sensors for Simultaneous Determination of Double Targets
    FEI Yan-Qun1, LUO Gui-Min1, FENG Guo-Dong2, FEI Qiang2, CHEN Huan-Wen2, LIANG Xue-Kai2, ZHAO Xiao-Jun3*, HUAN Yan-Fu1,2*
    2008, 29(1):  83-85.  doi:
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    New fluorescent silica nanoparticles for sensors simultaneous determination of double targets were synthesized via a reverse microemulsion method based on the fluorescence resonance energy transfer(FRET). Nanoparticle A was doped with a dye complex which consisted of two dye molecules, fluorescein and tetramethylrhodamine. These dye molecules were first linked with avidin and biotin, respectively. They then formed a stable dye complex through avidin-biotin bridge within the distance of FRET. Nanoparticle B was doped with fluorescein only. As a result of this combination, the nanoparticles emit double wavelengths when a single excitation wavelength is used. The results show that the fluorescent nanoparticles are promising fluorescent labeling reagents for the sensitive detection of double targets.
    研究论文
    Synthesis and Evaluation of a Trace for Peripheral Benzodiazepine Receptors
    LI Bin1, LI Jian-Feng2, FU Lei3, SUN Xiao-Guang1, LIU Jian-Jun1, HUANG Gang1*
    2008, 29(1):  86-89.  doi:
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    The 2-iodophenyl-imidazo[1,2-a]-pyridines tirfluoromethyl derivative(ITFZOL) was prepared to study the PBR. The [125I] analogue was prepared via iododestannylation reaction in radiochemical yields of 75%—85% and a specific activity>76 GBq/μmol. After injection of [125I] ITFZOL into mice through the tail vein, high accumulations of radioactivity were found in PBR-rich tissues such as adrenal, lung, kidney, heart, olfactory bulb and cerebellum. Per-administration of PBR-selective PK11195 displayed a significant reduction of radioactivity, suggesting a high specific binding of [125I] ITFZOL to PBR. The biological data reveal that [125I] ITFZOL is a potential and selective single photo emitting radioligand for PBR.
    Synthesis and Herbicidal Activities of 4-Alkoxy/benzyloxyphenyltetrazoles and 1,3,4-Oxadiazoles
    WANG Bao-Lei, LI Zheng-Ming*, LI Yong-Hong, WANG Su-Hua
    2008, 29(1):  90-94.  doi:
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    Tetrazoles and 1,3,4-oxadiazoles are important heterocyclic compounds with a wide range of pharmaceutical and biological activity. Their syntheses and herbicidal activity have been of interest for a long time. In our previous research, a series of 4-alkoxy(benzyloxy)benzamidines were synthsized and showed a favourable herbicidal activity and KARI inhibitory activity. For searching potent herbicidal activity compounds, in this paper, five 4-alkoxy/benzyloxyphenyltetrazoles and seventeen new 2-substituted-5-(4-alkoxy/benzyloxy)phenyloxadiazoles were designed on the basis of the structure of 4-alkoxy(benzyloxy)benzamidine and synthesized via 4-cyanophenol as the starting material. All synthesized novel compounds were confirmed by elemental analysis, 1H NMR and MS. The preliminary herbicidal assay indicates that some of them displayed a good herbicidal activity on di-cotyledonous rape(Brassica campestris) and mono-cotyledonous barnygrass(Echinochloa crusgalli).
    Multi-KNN-SVR Combinatorial Forecast and Its Application to QSAR of Fluorine-Containing Compounds
    TAN Xian-Sheng1,2, YUAN Zhe-Ming1*, ZHOU Tie-Jun2, WANG Chun-Juan1, XIONG Jie-Yi1
    2008, 29(1):  95-99.  doi:
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    To further understand the quantitative structure-activity relationship (QSAR) of fluorine-containing pesticide and improve the prediction precision of QSAR models, a novel nonlinear combinatorial forecast me-thod named Multi-KNN-SVR, multi-K-nearest neighbor based on support vector regression, was proposed. The novel method includes the following key steps: firstly, seeking the best kernel automatically based on the minimum mean square error (MSE); secondly, screening descriptors nonlinearly by F-test; finally, carrying out the combinatorial forecast with multiple KNN sub-models. Multi-KNN-SVR was applied to the QSAR for the antibacterial bioactivities of 33 fluorine-containing pesticides against 5 different plant diseases. The results of leave-one-out test show that screening descriptors and sub-models were essential, and the combinatorial forecast after screening sub-models could get a better precision than single KNN model. The predicte results also indicated that Multi-KNN-SVR had the advantages of high prediction precision (MSE=0.005—0.015, MAPE=2.136—3.164), high stability, strong generalization ability, structural risk minimization, non-linear characteristics and avoiding the over-fit in all reference models. Multi-KNN-SVR, therefore, can be widely used in QSAR and other related fields.
    Novel Method for Biomimetic Synthesis of Cyclohexyl Ketone Compounds
    LI Jian-Li, YIN Wen-Ting, ZHANG Jin, GUO Yuan, WU Xiang-Long, BAI Yin-Juan, SHI Zhen*
    2008, 29(1):  100-103.  doi:
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    The tetrahydrofolate coenzyme is the methyl source of the methylation for many materials (including the DNA and RNA) in the living body to transfer one carbon unit for the biosynthesis and metabolism. On the basis of the one-carbon unit transfer reaction of tetrahydrofolate coenzymes, six cyclohexyl ketone compounds were synthesized successfully with benzimidazolium salt as the tetrahydrofolate coenzyme model at formic acid oxidation level and Grignard reagent as a nucleophile to which one carbon unit was transferred via addition-hydrolysis reaction. Their structures were characterized by elemental analysis, 1H NMR, IR and MS spectra. A novel method for the convenient biomimetic synthesis of cyclohexyl ketone compounds was provi-ded. The reaction mechanism and the effects of reaction conditions on the yield were investigated.
    Expression and Identification of FMDV 3ABC Truncated Gene in Pichia Pastoris
    ZHENG Min1,2,3, JIN Ning-Yi2*, LI Chang2, LU Hui-Jun2, MA Ming-Xiao1, SHEN Guo-Shun1, HUO Xiao-Wei1, MA Hai-Li1, CHEN Xiao-Yue1, QU Yong-Gang1
    2008, 29(1):  104-108.  doi:
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    Foot-and-mouth disease virus(FMDV) is an important pathogen worldwide; consequently, an important goal is the developments of diagnostic methods. To acquire an optimal diagnostic antigen allows one to distinguish vaccinated anionals from infected animals, a recombinant expression plasmid pPIC9K-3ABCt was constructed by inserting of FMDV 3ABC truncated gene(525 bp) into yeast expression vector pPIC 9K. Se-condly, plasmid pPIC9K-3ABCt was linearized by BglII, and transformed into GS115 cells by electroporation. Positive clones were selected with MD/MM plates and confirmed by PCR and RT-PCR. Finally, expression product of 3ABCt was analyzed by SDS-PAGE and Western blot. The results show that the induced recombinant Pichia pastoris GS115/pPIC9K-3ABCt could secret 3ABC protein mainly in dimer form into culture supernatant, which had good immunoreactivity and antigen specificity and its molecular weight output was about 40000. Expression of 3ABCt protein reached peek at 96 h after induction, maximum expression was accumulated up to 18% of the total supernatant protein, and production was about 23.4 mg/L.
    Stability of a Hyperthermophilic Esterase APE1547 from an Archaeon Aeropyrum pernix K1
    XIE Gui-Qiu1,2, GAO Ren-Jun1, BI Yun-Feng1, WANG Zhong-Yu1, LIU Na1, FENG Yan1, CAO Shu-Gui1*
    2008, 29(1):  109-112.  doi:
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    The gene APE1547 from an archeaon Aeropyrum pernix K1 were cloned and expressed in E. coli BL21. The recombinant enzyme shows an esterase activity and its optimum reaction temperature was 90 ℃. In this paper, the stability of a hyperthermophilic esterase APE1547 from an archeaon Aeropyrum pernix K1 was studied. The experimental results indicate that APE1547 was one of the most stable hyperthermophilic enzymes. Its half-life was 20 h at 90 ℃(0.4 mg/mL), and it was stable in an alkalinous environment. At the same time, the change of the fluorescence and the activity was detected when the enzyme was thermally denatured. With the exposure of hydrophobic amino acids, its activity reduced gradually. Furthermore, this enzyme has a good pH stability and shows a good organic solvents resistance. The present results indicate that this enzyme will be useful in specific industry process such as high temperature or organic reaction.
    Electrochemical STM Investigation on Self-assembled Structure of a Tetraazacalixarenetriazine Derivative on Au(111) Surface
    CHEN Ting, YAN Hui-Juan, PAN Ge-Bo, WAN Li-Jun*, WANG Qi-Qiang, WANG Mei-Xiang*
    2008, 29(1):  113-116.  doi:
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    Electrochemical scanning tunneling microscopy(EC-STM) and cyclic voltammetry were employed to investigate the self-assembled structure of a new heteroatom-bridged calix(hetero)aromatics, tetraazacalixarenetrizaine derivative on Au(111) surface. High-resolution STM images reveal that the molecules form long-range ordered monolayers. Moreover, the molecule adopts a 1,3-alternate conformation. Two triazine rings lie flatly on Au(111) surface, while two phenyl rings were tilted. This could be attributed to a balance between intermolecular and molecule-substrate interactions.
    MCSS Analysis of Drug Binding Sites for Candida albicans N-Myristoyltransferase
    SHENG Chun-Quan1, ZHU Jie2, ZHANG Wan-Nian1*, XU Hui1, SONG Yun-Long1,ZHANG Min1, YAO Jian-Zhong1, MIAO Zhen-Yuan1
    2008, 29(1):  117-123.  doi:
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    NMT is a promising target for the development of novel anfifungal agents with a new mode of action. In order to know the important functional residues and regions in the active site of Candida albicans N-myristoyltransferase(CaNMT) in detail, multiple copy simultaneous search(MCSS) was used to identify the hydrophobic pockets, hydrogen-bonding sites and electrostatic negative sites. The results from MCSS calculation reveal that there were two hydrophobic pockets. One pocket was lined with Tyr107, Tyr119, Val108, Phe117, Phe123, Ala127, Phe176 and Leu33, the other pocket was lined with Phe115, Phe240 and Phe339. Moreover, two hydrogen-bonding sites were identified by MCSS calculations. Among those hydrogen-bonding residues, Tyr119, His227, Asn392 and Leu451 could form hydrogen bond with the benzofuran inhibitors and Tyr107, Asn175, Thr211 and Asp412 were newly discovered hydrogen-bonding residues, which were highly conserved residues across the NMT family and would play an important role in the design of NMT inhibitors with novel chemical scaffold. Important functional residue Leu451 could serve as both hydrogen-bonding site and electrostatic negative site, which was indispensable in inhibitor design. The above results could provide important clues for the de novo design and virtual high-throughput screening of novel NMT inhibitors.
    Preparation and Properties of a Novel Multiple Responsive Supramolecular Hydrogel Based on Host-Guest Interaction
    YAN Jun-Lin, LIU Jing, CHEN Xi, FANG Yu*
    2008, 29(1):  124-129.  doi:
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    A novel supramolecular hydrogel was prepared by utilizing the host-guest interaction between 6-deoxy-6-amino-β-cyclodextrin(β-CDNH2) and N,N′-bis(ferrocenyl-methylene)diaminobutane(FBI) in an aqueous phase. The phase state of the hydrogel is sensitive to the changes of temperature and pH. Furthermore, introduction of a chemical oxidant, (NH4)2Ce(NO3)6, resulted in dissolution of the gel, and correspondingly the color of the system changed from light yellow to dark green. SEM measurements reveal that the network structure of the hydrogel is characterized by belt-like fibers. It is the fibers that intertwine into 3-dimensional networks. 1H NMR, FTIR, CV, and XRD studies demonstrate that the host-guest interaction between FBI and β-CDNH2, and the intermolecular hydrogen bonding between β-CDNH2 are the main driving forces for the formation of the gel.
    Preparation of Au@SiO2 Core-shell Nanoparticles and Their Surface-Enhanced Raman Spectra
    FAN Xiao-Min, ZOU Wen-Jun, GU Ren-Ao, YAO Jian-Lin*
    2008, 29(1):  130-134.  doi:
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    Gold nanoparticles were prepared with chemical reduction method and the size was controlled via adjusting the molar ratio of citric acid to chloroauric acid. By measuring the TEOS and ammonia, the layer of SiO2 was attached onto gold nanoparticles with different thicknesses to produce Au@SiO2 core-shell nanoparticles. The relationship between the intensities of surface enhanced Raman spectroscopic(SERS) bands and the thickness of SiO2 was determined by employing thiophenol as the probe molecule. The results indicate that the electromagnetic enhancement(EM) was damped with the increase in the thickness of SiO2, and the damping effect was weaker that the dual-metal core-shell structure with the same size as the Au@SiO2. Moreover, the probe molecule was adsorbed onto the Au@SiO2 surface with physical interaction, and the probe was removed through the appropriate solvent for the cycle-SERS detection.
    Epoxidation of Styrene via Anhydrous t-Butylhydroperoxide Catalyzed by Supported Au/Fe(OH)3
    WANG Ya-Li1, SUN Jian-Hong2, XIANG Dan1, WANG Lu1, SUN Jian-Min1*, XIAO Feng-Shou1
    2008, 29(1):  135-139.  doi:
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    This paper reports the epoxidation of styrene by t-butyl hydroperoxide(TBHP) over the Au/Fe(OH)3 catalyst prepared by co-precipitation method. The influences of calcination temperature, chemical states of Au and Fe, gold loadings of the catalyst and reaction time on the activity of styrene epoxidation are studied in detail. The results suggest that the conversion and selectivity of styrene epoxide are significantly influenced by the calcination temperature and Au loadings.Au/Fe(OH)3 with a mass fraction 4.67% shows the best activity to the epoxidation of styrene, the conversion is 84.1% and selectivity is 71.5% under the reaction condition of 80 ℃ for 3 h. The XRD, XPS and Fe Mössbauer spectra indicate that Au and Fe chemical states are responsible for the good activity of Au/Fe(OH)3 catalyst. The synergistic effect of Au3+ and Fe(OH)3 leads to its good activity for the styrene epoxidation.
    Time-Resolved Spectral Analysis of Ultrafast Isomerization Dynamics of Retinal in Bacteriorhodopsin
    WU Yi-Shi1,2, ZHONG Sheng3, AI Xi-Cheng2, HU Kun-Sheng3, ZHANG Jian-Ping2*
    2008, 29(1):  140-143.  doi:
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    The ultrafast photoisomerization process of retinal in Bacteriorhodpsin's(BR) photocycle was investigated via femtosecond time-resolved absorption spectroscopy. Singular value decomposition(SVD) combined with model-based global fitting was employed to analyze the time-resolved spectra, and the related difference spectra(SADS) and the population dynamics of I460, J625 and K590 intermediates were derived on the basis of our proposed reaction scheme. The detailed photoisomerization pathways were discussed. Moreover, the SADS of Franck-Condon state(H intermediate), radiative transition of which accounts for the stimulated emission around 700 nm, was also detected, and its time constant was 0.04 ps. Our results prove the involvement of the H-intermediate in ultrafast photoisomerization process of retinal in BR.
    Investigation on Influence Factors and Mechanism of Microbial Fuel Cell
    ZHAN Ya-Li*, WANG Qin, ZHANG Pei-Pei, YAN Guang-Xu, GUO Shao-Hui
    2008, 29(1):  144-148.  doi:
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    Microbial fuel cell is a equipment in which microbial is used as anodic catalyst and chemical energy is directly changed into electrical energy. In this paper, a mediator- and membrane-less microbial fuel cell was constructed, domestic waste water was used as inoculant and sodium acetate was used as its fuel. The effects of concentration of acetate, outer resistance, temperature and oxygen addition on the cell were investigated, outer voltage and electrode potentials were monitored and microcosmic mechanism was proposed. The results show that the activity of the microbe adsorbed on the electrode is a key factor of the cell voltage, and the more active the microbe, the higher the outer voltage; the activity is affected by the concentration of the solution, temperature and oxygen addition; the voltage increases with the concentration increases and the relationship between outer electrical pressure and concentration is in agreement with Monod equation; the voltage remarkably reduces with the existence of oxygen that restrain the growth of the microbe; the voltage increases and the microbial activity gets enhanced, but when the temperature rapidly rises to 50 ℃, the microbial activity is lost and outer voltage is very low; the cathodic potential is controlled by the H+ concentration; the polarized cell is in agreement to general battery; the output power density is the function of outer resistance, and reach the biggest, 346 mW/m2, when outer resistance is 200 Ω.
    Singlet Excited State Energy Transfer Among Pigments in HL-LH2
    ZHAO Xiao-Hui1,2,3, LIANG Jun1,2, MA Fei1,2, SU Wen-Jie2, WANG Peng2*, FU Li-Min2, AI Xi-Cheng2, ZHANG Jian-Ping1,2
    2008, 29(1):  149-153.  doi:
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    Under excitation of 500 and 800 nm, femto-second time-resolved absorption spectroscopy was used to observe the characteristic absorption of carotenoids(Cars) with various conjugation lengths and bacteriochlorophyll a(BChl a) with different Qy bands, i.e. B800 and B850 aggregates, in the high light cultured peri-pheral light-harvesting complex(HL-LH2) from Rhodopseudomonas(Rps.) palustris. Spectroscopic dynamics analysis suggests that the complicated singlet excited state energy equilibrium possibly exists among various carotenoids and multi-channel singlet excited state energy transfer occurs between Cars and BChl as. B800 mainly accepts the excitation energy from S1 and S2 states of Cars, and B850 from the S1 state of Car with the longest conjugation length(conjugated double bonds number n=13) and B800 as well. The whole singlet excited state energy transfer process can be completed in 3—5 ps.
    Preparation and Properties of Cermets Inert Anode with Adding MnO2
    ZHANG Li-Peng1,2, YU Xian-Jin2*, DONG Yun-Hui2, LI De-Gang2
    2008, 29(1):  154-158.  doi:
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    Cermets with adding MnO2, used as the inert anode in aluminum electrolysis, were prepared. The effects of MnO2 on the properties of inert anode were researched. The inert anode on corrosion resistance properties were also studied, and determination of the conductivity of the sample in the temperature change range of 500—1000 ℃ was made. The effects of MnO2 on sintering properties of inert anode were investigated. The results indicate that MnO2 improved sintering properties, crystal of cermets with adding MnO2 grew ideally, the cermets inter anode had a high density, high anti-oxidation, corrosion resistance and high conductivity. The annual corrosion rate of cermets with adding MnO2 was 12.32 mm/a. The electric conductivity was stable and good, which belongs to the electric conductivity property of the semiconductor. The conductivity increased with temperature increasing. The conductivities of cermets with adding MnO2 was 67 S/cm at 850 ℃.
    Ab initio Study on Luminescent Mechanism of [Au(PH3)]+ Complexes with Aryl and Alkynyl Ligands
    JIAO Yu-Qiu1, PAN Qing-Jiang1,2, ZHANG Hong-Xing1*
    2008, 29(1):  159-164.  doi:
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    The structures of Au(I) complexes, H3PAuC≡CPh(a), H3Pau(C≡C-1,4-C6H4)Ph(b) and H3PAu(C≡C-1,4-C6H4)C≡CPh(c) were optimized by the ab initio MP2 and CIS methods for the ground states and excited states, respectively. It was shown that the electron transitions weaken the bonding between Au and ligands. The lowest-energy phosphorescent emissions from A3A′→1A′ were predicted at 530, 610, and 615 nm for complexes a—c, respectively, agreeing well with experimental data. The emissions were attributed to the pπ*(Ph)→pπ(Ph) transition nature modified by the Au→C charge transfer(MLCT) and the Au(6p)→Au(5d) transition (MCCT). With the increase of conjugated lengths of complexes, the participation of Au(p) orbital decreases in the excited state. Consequently, the corresponding emission wavelength redshifts.
    Interactions of [Mo6O19]2- and Its Derivatives Substituted with Organic Groups Inhibitor with SARS-CoV 3CLpro by Molecular Modeling
    SHAO Chen1, WANG Jian-Ping1, YANG Guo-Chun1, SU Zhong-Min1,2*, HU Dong-Hua1, SUN Chia-Chung2
    2008, 29(1):  165-169.  doi:
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    Polyoxometalates(POMs) were proved with the properties of both anti-tumor and anti-HIV. The potential anti-SARS activities of the polyoxometalates [Mo6O19]2- and its derivatives substituted with organic groups were investigated in this paper by molecular modeling method. The 3c like(3CL)protease hydrolyze, namely 3CLpro, is the key protease for virus replication as well as transcription, and thus can be taken as one of the key targets for anti-SARS drug design. InsightII/Dicover 3, affinity, Profile-3D modules were used to explore possible binding locations and properties for POMs/3CLpro interaction. We studied the energy changing tend and investigated the possible inhibiting mechanism of POMs' with SARS-CoV. The results show that POMs bind with 3CLpro in the active site with a high affinity, mainly via electrostatic interactions and H-bond interactions. For the POMs/3CLpro complex, POMs substituted with organic groups with higher negative charge are prefer to bind with 3CLpro than non-substituted ones, and this agrees well with relative quantum chemical calculations. Organic substitutions in ligands have an influence on the stability of complexes by steric hindrance. Our study may provide theoretical reference and illustrations to anti SARS-CoV drug design.
    Theoretical Study of Potential Energy Surface for the Reaction NO+HCCCO
    WANG Song1, YU Jian-Kang1,2*, DING Da-Jun2, SUN Chia-Chung1
    2008, 29(1):  170-173.  doi:
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    A mechanistic study of the NO+HCCCO reaction, in which products Pi with i=1,2,3,4 are involved, is carried out by means of CCSD(T)/6-311G(d,p)//B3LYP/6-311G(d,p)+ZPVE computational method to determine a set of reasonable pathways. It is shown from the potential energy surface that P1(HCCO+NCO) is the major product channel, with a minor contribution of both P3[HC(N)CO+CO] and P4(HCN+2CO), whereas the P2(HCCNO+CO) is less favorable. The present work will provide some useful information for the experimental studies.
    Theoretical Studies on Vibrational Frequencies and Decomposition Channels of HXeBr
    ZHU Hua1* , XIE Dai-Qian2
    2008, 29(1):  174-176.  doi:
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    Ab initio calculations at the MP2 and CCSD(T) levels of theory were performed to analyze the equilibrium structure and vibrational spectra of HXeBr compound. The calculated vibrational frequencies, corrected for anharmonicity and matrix effects, are 1492 cm-1(H—Xe stretching), 509 cm-1(bending) and 174 cm-1(Xe—Br stretching). These are in good agreement with the observed values. The energetic stabilities and decomposition channels(HXeBr→Xe+HBr and HXeBr→H+Xe+Br) are calculated via single-configurational CCSD(T) and multireference averaged quadratic coupled-cluster(MR-AQCC) methods, respectively. The calculation results indicate that the energy barrier for HXeBr→Xe+HBr and HXeBr→H+Xe+Br is 1.39 and 0.89 eV, respectively. The three-body decomposition channel is found to be the dominate decomposition channel for HXeBr.
    Theoretical Studies of the Structure Optimization, Frontier Orbitals and Properties of Bifluorene and Its Derivatives
    WANG Ji-Fen1,2*, FENG Ji-Kang2*
    2008, 29(1):  177-181.  doi:
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    The structures of bifluorene and its derivatives was optimized by the density functional theory with B3LYP/6-31G functional while their maximal absorption wavelength λabs were studied by employing the time dependent density functional theory(TD-DFT) and ZINDO. On the basis of fully optimized structures, the molecular orbitals of bifluorene and its derivatives DFE, DFA, DFBT, FDBO and FSCHD were analyzed by comparison. The derivatives DFE, DFA and DFBT were better conjugated and their HOMO-LUMO gaps were narrower than that of BF. So they were better conductor than BF. And the absorption spectra of them were red shifting. How-ever, FDBO and FSCHD were in the other way round. The thermochemical properties were studied in this paper and these properties were important to experiment. It is found that DFBT has the lowest total energy in these molecules from analyzing the thermochemical parameters.
    Theoretical Studies on Hydrogen overfall Mechanism for Catalyzed Hydroisomerization of n-Hexane
    AI Chun-Zhi1,2, SUN Ren-An1*, WANG Chang-Sheng1, MA Lin1, YANG Ling2
    2008, 29(1):  182-186.  doi:
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    The mechanism and the related reaction paths in the hydroisomerization of n-hexane were studied with DFT calculations at the B3LYP/6-311++G** level. Five possible transition states were theoretically predicted and verified by the vibration frequency analysis as well as the calculations of intrinsic reaction coordinates(IRC). Further more, the related reaction barriers were evaluated on the basis of single point energy with zero point vibration correction, and the distribution of natural charge was analyzed at MP2/6-311++G** level. Consequently, six pathways were found and the barrier energy of the main isomerization pathway is 42.52 kJ/mol.
    Synthesis and Properties of Core-shell Fluorosilicone-containing Acrylate Latexes
    HE Ling, XU Yan, ZHU Jiang-Gan, LIANG Jun-Yan*
    2008, 29(1):  187-192.  doi:
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    The core-shell silicon-containing fluorinated acrylate latex was obtained via semi-continuous seed emulsion polymerization in which butyl acrylate(BA) served as the core, methyl methylacrylate(MMA), methyl dodecafluorinacrylate(DFHMA in commercial name), 3-methacryloxypropyltrimethoxysilane(MPTMS) and methyltrimethoxysilane(MTMS)(BA/MMA/DFHMA MPTMS/MTMS) served as the shell of copolymer. FTIR, SEM-EDX, and DSC were used not only to analyze the properties of the latexes and films, but also to investigate the effect of DFHMA and MPTMS/MTMS content on the latexes and films. TEM was employed for characterizing the morphology structure and the particle size of the core-shell latex. The results indicate that the copolymers presented uniform spherical core-shell partials with 20—30 nm in diameter, the content of F and Si element on the surface of films have a great effect on the characteristics of the films, and when m(DFHMA)/m(MPTMS+MTMS)=3/1, the film shows much more favorable characteristics both in latex and in film.
    Synthesis and Characterization of Hyperbranched Poly(β-cyclodextrin)
    TIAN Wei, FAN Xiao-Dong*, JIANG Min, DING Wen-Xiu, WANG Hao, LIU Yu-Yang
    2008, 29(1):  193-196.  doi:
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    Hyperbranched poly(β-cyclodextrin) was successfully prepared via hydrosilylation from ABx type cyclodextrin monomer. The molecular structures of ABx monomer and hyperbranched polymer were characterized with 1H NMR, 13C NMR, 29Si NMR, MALDI-TOF MS and elemental analysis. In addition, molecular weight, molecular weight distribution(MWD) and intrinsic viscosity of hyperbranched polymer were obtained via size exclusion chromatography/multi-angle laser light scattering(SEC/MALLS) technology.
    Orthogonal Test of Preparation of Poly(L-glutamic acid) Through Deprotection of Poly(γ-benzyl L-glutamate)
    XIE Yong-Tao1, YIN Jing-Bo1*, ZHAO Chang-Wen2, CHEN Xue-Si2*
    2008, 29(1):  197-200.  doi:
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    Poly(L-glutamic acid)(PLGA) was prepared by removing the benzyl groups from poly(γ-benzyl L-glutamate)(PBLG) through 33%(volume fraction) HBr and acetic acid solution. Orthogonal test method was applied to study the effect of temperature, the reacting time, the quantity of the solvent and 33%HBr and acetic acid solution on the molecular weight of PLGA during the process of deprotection.The result show that PLGA molecular weight would be decreased with the increase of the temperature, the reacting time, and the solvent quantity, for the degradation of PBLG. However, the effect of HBr was reverse, for the acidity of 33%HBr and acetic acid solution was weaker than that of dichloroacedic acid(Cl2HAc), and PBLG could not be dissolved in 33%HBr and acetic acid solution.
    Comparison of Formation Mechanism of Nanocapsules Through Miniemulsion Polymerization in the Presence or Absence of N-Isopropyl Acrylamide
    CAO Zhi-Hai, SHAN Guo-Rong*
    2008, 29(1):  201-205.  doi:
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    According to the morphologies of latexes with and without the crosslinking agent, the escape of hydrocarbon which can be suppressed by the introduction of some amounts of crosslinking agent was considered as the main reason to form small solid particles. On the basis of these results, the comonomer, N-isopropyl acrylamide, was introduced in the system for synthesis of nanocapules through miniemulsion polymerization with liquid hydrocarbon as the template. The oligomers of poly(N-isopropyl acrylamide)(PNIPA) which can be dehydrated and separated from aqueous phase at polymerization temperature were adsorbed by the mini-droplets. Due to the thermodynamic force and electrostatic interaction, the oligomer radicals of PNIPA anchoring at the interface of droplets make the interface to be the loci of polymerization. Monomers diffused from the interior of droplets to supply for further polymerization. The nanocapsules can be obtained through the encapsulation of hydrocarbon by the newly-produced polymers separated at the interface of droplets. The mechanisms of formation of nanocapsules in the system with or without NIPA were compared.
    Synthesis and Characterization of Novel Bioadhesive Material Thiolated Chitosan
    WANG Xin, ZHENG Chao , ZHANG Xin-Ge , WANG Zhen , LI Chao-Xing*
    2008, 29(1):  206-211.  doi:
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    The use of mucoadhesive thiolated polymers as the carriers can improve the adsorption of drugs by prolonging the residence time on the nasal mucosa on the basis of the formation of disulphide bonds between thiol groups on polymer and cysteine-rich domains of mucus glycoproteins. In this study, a novel thiolated polymer, N-acetyl-L-cysteine-g-chitosan conjugate(CS-NAC) was synthesized and characterized. Swelling and mucoadhesive properties of CS-NAC conjugates were evaluated in vitro. The cytotoxicity of CS-NAC conjugates was measured on L-929 mouse fibroblast cells by utilizing MTT method. The obtained CS-NAC conjugate displayed the most content of thiol group (589.3±38.6) μmol/g. The conjugates exhibited a fast swelling behavior in comparison to the unmodified chitosan. The mucoadhesive properties of CS-NAC conjugate showed more than 30-fold increase in mucoadhesion time and 3-fold increase in adhesive force versus the unmodified chitosan. Moreover, CS-NAC did not cause a significant increase in cytotoxicity. Therefore, the novel thiolated chitosan is a promising potential bioadhesive material.
    Preparation and Swelling Behaviour of Polyampholyte Hydrogels Composed of Acryloyloxyethyl-trimethyl Ammonium Chloride and Acrylic Acid
    XUE Dong-Hua1, WANG Ji-Hua1, SU Xue-Feng2, XU Kun2, WU Xiu-Li1, ZHANG Wen-De2, WANG Pi-Xin2*
    2008, 29(1):  212-216.  doi:
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    A series of poly(acryloyloxyethyl trimethyl ammonium choride-co-acrylic acid) hydrogels were synthesized by solution polymerization and the structure of hydrogel was characterized by FTIR and NMR. Meanwhile, the swelling behavior of hydrogels in distilled water with vairous pH values and the salt solutions with different concentrations were investigated. The results show that the hydrogel with equal molar negative charges and positive charges presented an antipolyelectrolyte effect. Ionic strength drastically affected the swelling behavior of hydrogels. At the same time, the swelling kinetic parameters of swelling process of hydrogels were also calculated in salt solutions with different concentrations and the results illuminated that the first 60% swelling process of hydrogels was governed by Fickian diffusion mechanism (n≤0.5) in the salt solution with a high ionic strength. With the increase of ionic strength, the swelling ratio of the hydrogels and diffusion coefficients increased.
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