Table of Content

10 June 2010, Volume 31 Issue 6

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Contents

Content of Chemical Journal of Chinese Universities Vol.31 No.6(2010)

2010, 31(6):  0. 

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Review

Bionics and Biomimetic Materials Bioinspired by Natural Spider Silks

LIU Quan-Yong, JIANG Lei*

2010, 31(6):  1065-1071. 

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Learning from the nature and being bioinspired, we can design, synthesize and prepare novel biomimetic materials based on bionics, which has been developing rapidly in the latest years. Natural spider silk is a kind of natural biologic protein elastomeric fiber, which presents high specific strength(5 times than that of steel), excellent elasticity(10 times than that of Kevlar 49) and toughness(the highest fracture energy in fibers). It is one of the best structural and functional materials made by the nature, and has great potential applications in the fields of aviation and spaceflight, military, building, biomedicine etc. Recently, the studies on spider silk inspired biomimetic materials have met a chance, and many original methods of bioinspired design have been shown. This paper reviews the development of biomimetic materials bioinspired by natural spider silks from different bionics angles, and some opinions and ideas are put forward.

Letters

Synthesis and Characterization of 5,5′-Dimethyl-2,2′-bisindan-1,1′,3,3′-tetrone

LI Ping*, MENG Ji-Ben

2010, 31(6):  1072-1074. 

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Based on the synthesis of 2,2′-bisindan-1,1′,3,3′-tetrone(1), 5,5′-dimethyl-2,2′-bisindan-1,1′,3,3′-tetrone(2) was obtained. This paper described the synthetic process and confirmed the characteristic of compound 2 by elemental analysis, ¹H NMR, FTIR and MS, then discussed a possible existing form. Compound 2 maily existed as en-ol form and had H-bonds in the molecule. At the same time, the ESR value of compound 2 was given as g=2.0042, could form stable radical.

Novel Two-photon Fluorescent Probe 2,7-BHVC for DNA Imaging

JIA Peng-Fei, LIU Heng*, ZHANG Yuan-Hong, LIU Xin, ZHAO Ning, YU Xiao-Qiang*

2010, 31(6):  1075-1077. 

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2,7-BHVC, a novel two-photon fluorescent probe for DNA with large two-photon excited fluorescence action cross sections, was synthesized and characterized. It emits weak two-photon fluorescence in aqueous solution while its two-photon fluorescence is strongly restored upon binding to DNA. The two-photon imaging in cell demonstrated that 2,7-BHVC can exactly label nuclear DNA.

Synthesis and Characterization of New Electroactive Polyaryletherketone Containing Benzonitrile Structure

YAO Lei, CHAO Dan-Ming, LIU Xin-Cai, LI Zhi-Liang, WANG Ce*

2010, 31(6):  1078-1080. 

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A new electroactive polyaryletherketone containing benzonitrile(EPEEK-CN) was synthesized from 2,6-difluorobenzonitrile, p-benzenediol and difluoromonomer containing phenyl-capped aniline tetramer segment, via ternary polycondensation. The obtained EPEEK-CN shows certain extent solubility in organic solvents, and its film casted from DMAc solution exhibits interesting electrical, mechanical and dielectric properties.

Synthesis and Hybrid of a(4-Phosphonic acid)phenylated Poly(arylene ether sulfone)

LIU Bai-Jun*, LI Xue-Feng, GUO Mei-Mei, LIU Chang, LI Long, JIANG Zhen-Hua

2010, 31(6):  1081-1083. 

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A bromine-containing poly(arylene ether sulfone) was synthesized from a(4-bromo)phenylhydroquinone monomer. A phosphonated derivative was prepared based on above brominated polymer using palladium-catalyst. Aimed at improving the properties for fuel cell applications, a composite membrane was obtained by incorporating sulfonic acid-functionalized polysilsesquioxane into the phosphonated polymer through a sol-gel processing. Both phosphonated membrane and its hybrid membranes show good thermal and dimensio-nal stability. The hybrid membrane has low methanol permeability of 1.07×10^-7 cm²/s and proton conducti-vity of 0.06 S/cm at 80 ℃.

Articles

Preparation of Au-Ag Nanoflowers by Seeding Approach

SUN Xue-Jiao, ZHAO Li-Li, JI Xiao-Hui*, YANG Wen-Sheng

2010, 31(6):  1084-1087. 

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Au-Ag nanoflowers were prepared by gold nanoflowers as the seeds and the mixture of AgNO₃ and ascorbic acid as the growth solution. With increasing the molar ratio of Ag/Au from 0∶1 to 0.3∶1, the surface plasmon band of the Ag-Au nanoflowers shifted from 592 nm to 518 nm. When the molar ratio was higher than 0.3∶1, there was obvious self-nucleation of Ag and the resulting Ag-Au composite particles became spherical-like in shape. Surface enhanced Raman scattering(SERS) measurements by p-mercaptobenzoic acid(p-MBA) indicated that the Au-Ag nanoflowers exhibited improved SERS activity than the gold ones.

Mesoporous Carbon Preparation by in-situ Carbonization via a Reaction Under Autogenic Pressure at Elevated Temperature

ZHAO Jun-Hua, LI Hong-Liang*, LIN Qing, LI Ke-Xun, PENG Zhi, ZHAO Xiu-Song

2010, 31(6):  1088-1092. 

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As-prepared SBA-15 synthesized with different contents of surfactant was put into a swagelok-like high pressure reactor to yield a carbon/porous silica composite. The surfactant was then in-situ carbonized and deposited inside the channels of the pores of SBA-15 via a reaction under Autogenic Pressure at Elevated Temperatures(RAPET). The surfactant acted as both soft-template for as-SBA-15 and carbon precursor for the carbon/porous silica composite. Mesoporous carbon was obtained after etching the silica using an H₂O/ethanol solution of NaOH. Nitrogen adsorption/desorption measurements show that the carbon materials possess a high surface area and a narrow pore size distribution. The advantage of the RAPET process, which can simplify the experiments, has been verified with control experiments by calcining the as-prepared SBA-15 in a porcelain boat under nitrogen atmosphere.

Porous Hydroxyapatite Nanoparticles as a Carrier of Ascorbic Acid

SHAO Feng-Wei, CAI Yu-Rong, YAO Ju-Ming*

2010, 31(6):  1093-1097. 

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Hydroxyapatite(HAP) is the most important ceramic material for biomedical applications for drug carrier and bone fillers because of its similarity to the biominerals in bone and hard tissues in mammals. It is one of few materials that are classed as bioactive, meaning that it will support bone ingrowth and osseointegration when used in orthopaedic applications. In this work, HAP nanoparticles were fabricated by chemical co-precipitation method with the assistant of the ultrasonic treatment in the present of ascorbic acid(AA). The as-prepared HAP nanoparticles were characterized by TEM, nitrogen adsorption, XRD, FTIR and ultraviolet spectrophotometer. The results showed that the porous HAP nanoparticles were obtained, which had an average diameter of about 140 nm and an average pore diameter of about 15 nm. The porous particles could load AA and the release speed of AA could be controlled by the ultrasonic treatment with different powers. This work indicated that the porous HAP nanoparticle was a promising candidate for drug carrier.

Preparation and Characterization of Monodisperse α-Fe₂O₃ Nanostructured Hollow Submicrosphere

LI Qun-Yan*, LOU Zai-Liang, WANG Zhi-Hong, XIE Lin-Yan, WEI Qi, NIE Zuo-Ren

2010, 31(6):  1098-1102. 

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The home-made monodisperse SiO₂ submicrospheres were coated with β-FeOOH by a new solution growth method. The size of SiO₂ submicrospheres had great influence on the microstructures of β-FeOOH coatings. When the average diameter of the submicrospheres was 250 nm, the β-FeOOH coating was uniform and the average thickness of β-FeOOH coatings was about 35 nm after the first cycle of coating. The thickness of β-FeOOH coatings increased greatly with multistep coating. After three cycles of coating, the thickness of β-FeOOH coatings increased to about 100 nm. The core-shell composites were immersed in NaOH solution(5%, mass fraction) at 40 ℃ for 24 h to remove the silica cores and then calcined at 600 ℃ for 24 h to prepare the monodisperse α-Fe₂O₃ hollow submicrospheres. The α-Fe₂O₃ shells in the hollow submicrospheres were constructed with α-Fe₂O₃ nanorods interconnected.

Highly-Ordered Hierarchical Composite Pore Materials Using Natural Plants as Templates

MA Jin-Yan, QU Feng-Yu*, XU Ying-Pu, LI Xiao-Feng

2010, 31(6):  1103-1107. 

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Two kinds of highly-ordered hierarchical pore materials with large poresize of 40—80 μm and mesoporous phase in inner-wall were synthesized successfully using two kinds of natural plants as macroporous templat, P123 as mesoporous templat. The hydrothermal stability of the samples was investigated in 37 ℃ water. Scanning electron microscopy(SEM), powder X-ray diffraction(XRD), high-resolution transmission electron microscopy(HRTEM) and N₂ adsorption/desorption are used to characterize the structure and properties of the products. The results confirmed that as-synthesized products own the macroporous and mesoporous phases. And the sample prepared with the stem of cattail as template shows good hydrothermal stability. This method can be used to replicate macroporous plant templates precisely. Since the aperture and pore structure of different plants are variable, it provides a natural condition for the synthesis of materials of different aperture holes and pore structure, and the organizational structure of the pore is to transport nutrient and water, so the hierarchical porous materials may have more superrior performance and application in the field of macromolecules separation, bone tissue regeneration ang drug delivery.

Synthesis of β-MnO₂ Nanofibers Based on MCM-41 Template and Their Catalytic Decomposition of Methylene Blue Dye

YANG Ze-Heng*, LI Hong-Yan, ZHANG Wei-Xin

2010, 31(6):  1108-1112. 

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β-MnO₂ nanofibers were successfully prepared based on MCM-41 mesoporous template. Firstly, Mn-MCM-41 was synthesized by impregnating mesoporous MCM-41 template with an aqueous ethanol solution of Mn(NO₃)₂ and heating at 450 ℃ for 4 h under air, and then the manganese oxide was obtained through dissolving the MCM-41 template with NaOH solution. Through X-ray diffraction, high resolution transmission electron microscopy and N₂ adsorption and desorption isotherm characterizations, the as-prepared manganese oxide was shown to be the pure phase of β-MnO₂ nanofibers with diameters less than 3 nm. These ordered β-MnO2 nanofibers formed a mesoporous structure similar to the MCM-41 template, with a high surface area of 136.5 m²/g. We demonstrated the high catalytic efficiency of β-MnO₂ nanofibers as catalyst in the oxidation of methylene blue(MB) dye with H₂O₂. The decoloration rate of 60 mg/L MB solution reached 97.59% within 100 min, indicating that the catalyst can degrade high concentration of MB solution efficiently.

Photoluminescence Properties of ZnO Nanorod Films Prepared by Wet-chemical Method

WEN Yan, WANG Yu-Hua*

2010, 31(6):  1113-1117. 

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Pure ZnO nanorod films were fabricated on nonconductive glass substrates by the simple wet-chemical method at 80 ℃. The structures and morphology of as-gown ZnO nanorod films were investigated by X-ray diffraction(XRD) and scanning electron microscopy(SEM). The results show that the nanorod array at the growth time of 30 min is Wurtzite structure and the mean diameter is about 80—90 nm. Besides, the photoluminescence(PL) properties of ZnO nanorod films at different low anneal temperatures as well as different anneal atmospheres are also studied. It is indicated that the ZnO film annealed at 450 ℃ in O₂ atmosphere for 1 h shows a stronger visible emission in the range of 550—750 nm with a maximum peak at 650 nm than the films annealed in the air and 5%H₂/95%N₂ atmosphere, and the broad absorption band of the sample(200—370 nm) is well matched with the emission wavelength of the long-ultraviolet(long-UV) light emitting diodes(LEDs)(λ_ex=350—420 nm).

CdTe/CdS Semiconductor Quantum Dots as a Highly Sensitive Sensor for Pesticide Paraquat

BIAN Qian-Qian, LIU Ying-Fan, YU Jun-Sheng*

2010, 31(6):  1118-1125. 

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The highly fluorescent water-soluble CdTe/CdS quantum dots(QDs) have been synthesized with tiopronin(TP) as a stabilizer and thioacetamide(TAA) as a sulfur source. The interaction of as-prepared CdTe/CdS QDs with the ten kinds of pesticides demonstrates that QDs fluorescence could be strongly quenched by paraquat at room temperature. When ten kinds of 4.76×10^-6 mol/L pesticides were added to 6.0×10^-4 mol/L CdTe/CdS QDs solution, respectively, maximum quenching observed was 87.3% for paraquat and 0.1%—5.1% for other nine kinds of pesticides, such as acephate, phoxim, triadimefon, acetochlor, dichlorvos, cypermethrin, acetamiprid, glyphasate-isopropylammonium and malathion. The result shows that the CdTe/CdS QDs is highly sensitive sensor for paraquat. The quenching mechanism of the CdTe/CdS quantum dots by paraquat has been investigated by absorption spectroscopy and time-resolved luminescence technique. The intensity Stern-Volmer plot for quenching by paraquat shows clear upward curvature with K=2.03×10⁶. The lifetime Stern-Volmer plot is linear with K=4.25×10⁵ , and shows less quenching than the intensity data. It is clear that the fluorescence intensity of QDs is decreased by both complex formation with paraquat as well as collisional quenching by paraquat. A highly sensitive fluorimetric method for the determination of paraquat is established by using CdTe/CdS QDs as a sensor. The calibration curve is linear over the concentration range of 9.90×10^-9—1.50×10^-6 mol/L with a correlation coefficient of 0.999, and a limit of detection of 6.39×10^-9 mol/L. The proposed method has been applied to the determination of paraquat residues in rice, wheat-flour, lettuce leaves and waste-water samples with standard addition recoveries of 82.2%—98.5% and RSD of 2.62%—8.35%.

Influence of the Number and Relative Position of the Interacting Groups in Template Molecule on Molecular Imprinting Effect

ZHANG Tie-Li*, LIU Feng, LI Ke-An

2010, 31(6):  1126-1130. 

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In order to explore the influence of the interacting group′s number and relative position of the template molecule on molecular imprinting effect, in the present study four molecularly imprinted polymers(MIPs) were prepared using a series of hydroxybenzoic acids with different numbers of —OH groups and their positio-nal isomers such as 3,4,5-trihydroxybenzoic acid(3,4,5-THBA), 3,4-dihydroxybenzoic acid(3,4-DHBA), 2,4-dihydroxybenzoic acid(2,4-DHBA) and 3-hydroxybenzoic acid(3-HBA) as model templates, respectively, acrylamide as functional monomer, ethyleneglycol dimethacrylate as cross-linker and acetonitrile(MeCN) as porogen by bulk non-covalent imprinting technique. The molecular recognition performances were characte-rized by high-performance liquid chromatography. The results showed that all of the imprinted polymers exhibited molecular imprinting effects for the corresponding templates and the imprinting factors were 5.51, 5.55, 2.60 and 2.03 for 3,4,5-THBA, 3,4-DHBA, 2,4-DHBA and 3-HBA, respectively, in the mobile phase of H₂O/MeCN(volume ratio, 1:99). Furthermore, the comparison of molecular recognition ability was made among them and gentisic acid-, salicylic acid-, 4-hydroxybenzoic acid-imprinted polymers, which were previously prepared under the same conditions as the above four hydroxybenzoic acids-imprinted polymers except for the template molecules. By comparative study on all of the above mentioned hydroxybenzoic acid-imprinted polymers, the following conclusions are drawn: (1) the template with multi-functional groups facilitates the preparation of MIP with high imprinting efficiency; (2) it was found that the positions of —COOH relative to —OH on the benzene ring have marked influence on the imprinting effects of templates. Specifically, the imprinting efficiency is higher for the template with —COOH and —OH at para-position than that at meta-position, whereas the imprinting effect will decrease if —COOH and —OH are at ortho-position owing to their forming intramolecular hydrogen bond. In addition, a baseline separation of the mixture of 3,4,5-THBA and 2,4-DHBA was obtained on 3,4-DHBA-imprinted polymer, which is a close analogue of 3,4,5-THBA. This provides the potentiality for the selective separation and detection of bioactive 3,4,5-THBA.

Fe₃O₄@Au Nanoparticles as Labels for Electrochemical Immunodetection of E.coli in Water

LIU Hui-Jie, TENG Ying-Qiao, ZHANG Xin-Ai, FU Ying, ZHANG Wen*, JIN Li-Tong

2010, 31(6):  1131-1136. 

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Fe₃O₄@Au nanoparticles were synthesized in this paper. The surface of nanoparticles was modified with horseradish peroxidase(HRP)-anti-E.coli antibody for amplified electrochemical immunoassay of E.coli. Poly-thionine(PTH) film was electro-polymerized on the GCE as an electron-transfer mediator. Gold nanoparticles(GNPs) on the PTH film constructed an effective antibody immobilization matrix. Using the typical sandwich type immmunoassay, E.coli could be detected according to the H₂O₂ reduction currents catalyzed by HRP labeled on anti-E.coli antibody. The method allowed quantitative determination of E.coli concentration from 50 to 1×10⁵ cfu/mL, with a detection limit of 20 cfu/mL. By introducing pre-enrichment steps, a concentration of 2 cfu/mL E.coli was detected with this method.

Studies on Chemical Constituents of Compound Indigowoad Root Granule by Mass Spectrometry

LIU Shu1,3, YAN Jun2, LI Hui-Lin1, SONG Feng-Rui1, LIU Zhong-Ying2, LIU Zhi-Qian

2010, 31(6):  1137-1142. 

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Muti-tandem electrospray ionization mass spectrometry(ESI-MSⁿ) and Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS) have been applied to analyse the chemical constituents from water and 95% ethanol extract of Compound Indigowoad Root Granule. A number of compounds were identified including amino acid, sugar and their derivatives, organic acid, primary products of the Maillard reaction of amino acid with monosaccharide and epigoitrin. This method is sensitive and rapid, suitable for analyzing the chemical composition of traditional Chinese medicine extract.

Differential Proteomic Study of Human T Lymphocytic Leukemia Protein Induced by Ionizing Radiation

LIANG Feng, SHI Ying, ZHANG Xuan, LIU Zhong-Ying, LIU Zhi-Qiang*

2010, 31(6):  1143-1147. 

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Two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrorometry(MALDI-TOF-MS) have been acknowledged as the efficient methods in proteomics studies. In this report, the total proteins of human T lymphocytic leukemia(Jurkat cells) treated by ionizing radiation were separated with two-dimensional electrophoresis. The differential expression of cellular proteins induced by ionizing radiation was analyzed by PDQUEST software. Six differential protein spots were identified by MALDI-TOF-MS, including Lamin B1, heterogeneous nuclear ribonucleoprotein, p47 protein isoform a, alternative splicing factor 1, prohibitin, and 6-phosphogluconolactonase. The results may help researchers better understand the underlying mechanism involved in cellular protein alteration induced by ionizing radiation.

Synthesis of pH Probe Based on Styrylcyanine Dyes and Fluorescence Image in Live Cell

WANG Bing-Shuai, WANG Li, WU Tong, YANG Zhi-Gang, PENG Xiao-Jun*

2010, 31(6):  1148-1151. 

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Fluorescent pH indicators have been widely applied in recent years to monitor changes in intracellular pH. Though some pH probes were synthesized and applied to sense the acidic organelles in live cells. However, the syntheses of these probes were very complicated. So, one pH fluorescence probe based on amino-styrylcyanine was synthesized with good yield and its purification was easy. Its abilities as pH probe were tested in ethanol-water solution. The results showed the absorption intensity of the base form(short-wavelength) decreased with the decreasing of pH, at the same time, the absorption intensity of the protonated forms(long-wavelength) increased. The color of the solution changed from yellow to pink. The base form had no fluorescence, but the fluorescence intensity of the protonated form increased remarkably. The pK_a of the probe was about 4.97. Live cell fluorescence images indicated the probe possesses good cell membrane permeation and can associate with lower pH yield inside the cytosol which can be applied to sense acidic organelles in live cells.

Purification and Characterization of New Special Saikosaponin-glycosidase

FU Yao-Yao, AN Jia-Yan, YU Hong-Shan, SONG Hai-Mei, SU Xiao-Feng, ...

2010, 31(6):  1152-1157. 

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Radix bupleuri, a well-known traditional Chinese herb-drug, is often used to treat common cold with fever. One of the major physiologically active ingredients in radix bupleuri is saikosaponin which has the properties of anti-inflammation, anti-hypersusceptibility, anti-thrombus. The natural structures of saikosaponins are not suitable for physiological or pharmacological effects, the enzymatic transforming generally improves the bioactivity of natural productions. In this paper, a new special saikosaponin-glycosidase hydrolyzing 3-O-β-(1→3)-glucoside and 3-O-β-fucoside of saikosaponin A or B2 was isolated from Aspergillus oryzae c42 strain, purified and characterized. The methods of centrifugation, ammonium sulfate precipitation, ion-exchange chromatography on DEAE-cellulose column and vertical slab polyacrylamide gel electrophoresis(PAGE) were used to purify the enzyme, and its partial characteristics were studied. The molecular weight of saikosaponin-glycosidase was about 58000 by SDS-PAGE. The enzyme hydrolyzed 3-O-β-(1→3)-glucoside of saikosaponin A or B2 into 3-O-β-fucoside-saikosapogenin A or B2, and further hydrolyzed 3-O-β-fucoside of 3-O-β-fucoside-saikosapogenin A or B2 into their aglycone(saikosapogenin A or B2) exhibiting significant differences from all previously reported glycosidases. The optimum temperature of the saikosaponin-glycosidase was 40 ℃; the optimum pH was 5.0. The activity of this enzyme was not apparently affected by Na⁺ and K⁺ ions, but it was significantly inhibited by Cu²⁺, Hg²⁺ and Ag⁺ ions; and slightly affected by Ca²⁺ and Mg²⁺ ions. Further study on saikosaponin-glycosidase will bring new insight to the understanding of glycosidases.

Synthesis of β-Indolylketones Catalyzed by BrΦnsted Acidic Ionic Liquid [HSO₃-bpy][HSO₄]

YU Chuan-Ji, LIU Chen-Jiang*

2010, 31(6):  1158-1161. 

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The BrΦnsted acidic ionic liquid [HSO₃-bpy][HSO₄] was reported as an efficient catalyst for the Michael addition reaction of indoles to α,β-unsaturated ketones. The reactions were carried out at 80 ℃ in acetonitrile for 3 h with stirring. Satisfactory results were obtained, with excellent yields and a simple experimental procedure. In addition, the ionic liquid was environmentally friendly and reused for three times without any noticeable decrease in the catalytic activity.

Synthesis and Biological Activities of Organotin 2-[(1,2,4-Triazol-1-yl)methylthio]benzoates

ZHANG Xiao-Yan, YANG Guang, ZHANG Jun, ZENG Guang-Tong, TANG Liang-Fu*

2010, 31(6):  1162-1166. 

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Triazole and its derivatives have attracted broad attention owing to their good coordination ability as well as extensive biological activities. In this paper, a new carboxylic acid with triazole moiety, namely 2-[(1,2,4-triazol-1-yl)methylthio]benzoic acid, was synthesized by the reaction of thiosalicylic acid with 1-chloromethyl-1,2,4-triazole-HCl. Five organotin 2-[(1,2,4-triazol-1-yl)methylthio]benzoates were obtained upon treatment this acid with (R₃Sn)₂O(R=Et, n-Bu, Ph), Cy₃SnOH(Cy=cyclohexyl) and Et₂SnO. The molecular structure of tri(n-butyl)tin 2-[(1,2,4-triazol-1-yl)methylthio]benzoate determined by X-ray crystallography showed that the tin atom was a five-coordinate distorted trigonal bipyramidal geometry with the exodentate nitrogen atom on 4-position of triazole ring and carboxyl oxygen atom occupying the apical position. Moreover, this complex formed a linkage coordination polymer through the intermolecular Sn…N interactions. All these complexes displayed good antifungal activities in vitro against Alternaria solani, Cercospora arachidicola, Gibberella zeae, Physalospora piricola and Botrytis cinerea.

Solid Synthesis and Photosensitive Properties of Chloroindium Phthalocyanine

TAN Ting-Feng, WANG Shi-Rong*, BAI Xiang, LI Xiang-Gao

2010, 31(6):  1167-1171. 

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Metallophthalocyanines are known not only as classical dyes in practical use but also as modern functional materials. However, detailed preparation of chloroindium phthalocyanine wasn′t reported up to the present. In this paper, chloroindium phthalocyanine was synthesized by the solid reaction of urea, phthalic anhydride, molybdic ammonium with hydrated indium trichloride using acetic sodium as catalyzer. The structure was verified by elemental analyst, UV-Vis, IR and XRD. Molar ratio of materials, catalyzer, reaction temperature and reaction time were discussed on the effect of yield of chloroindium phthalocyanine, so the optimal conditions were summarized as follows: n(urea)∶n(phthalic anhydride)∶n(indium trichloride)=14∶4.5∶1, acetic sodium was used as catalyzer. Firstly, reaction mixture was kept at 130 ℃ for 0.5 h, and then the reaction was carried out at 220 ℃ for 4 h. 88% H₂SO₄ was used to purify the product. In addition, the photosensitive properties of photosensitive resistance films were also studied. It was found that when 0.2 g chloroindium phthalocyanine and 0.6 g PVB were used to prepare photosensitive resistance films, the optimal dosage of dispersant butanone-cyclohexanone is 36 mL. The resistance sensitivity and integral ratio sensitivity of the chloroindium phthalocyanine films were over 1.50×10⁸ and 30 μA/(lx·V), respectively. These results show that chloroindium phthalocyanine films have good photosensitive properties.

Synthesis of Gambogic Acid Oxidative Analogues and Their Dimension Quantity Structure-activity Relationship Analysis

WANG Jin-Xin, YANG Yan, MA Jun-Hai, ZHANG Lei, GUO Qing-Long, YOU Qi-Dong

2010, 31(6):  1172-1178. 

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35,40-Dihydroxyl-6-methoxyl-gambogic acid methyl ester(1), 9,10-dihydroxyl-6-methoxyl-gambogic acid methyl ester(2) and 2-deisohexylene-2-(2-formyl)ethyl-6-methoxyl-gambogic acid methyl ester(3) were first synthesized. And their antitumour activities on several cancer lines were tested. Meanwhile via Tripos Sci QSAR software calculationthe QSAR equation explains the relationship between activity and structure with 2D QSAR method, and the biological activities are closely related to polarity volume ratio, the absolute value of the total charge, valence connectivity indexes and molecular volume. Our research can provide some guide meaning for the following research on studies of gambogic acid derivates.

Synthesis of Fluoroalkyl Substituted Biphenol A Derivatives

TANG Ting, YANG Xue-Yan, CHEN Xi, WU Fan-Hong*

2010, 31(6):  1179-1183. 

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Synthesis of new biphenol A derivatives are significant due to their utility as monomers. In this paper, the fluoroalkylation of phenol derivatives initiated by sodium dithionite in the presence of CTMAB as phase catalyst was investigated to give fluoralkyl phenols. When biphenol A was used as the substrate, some new biphenol A derivatives was obtained. Mono-, di- or tetra-fluoroalky subtstitued biphenol A derivatives, which may be important monomers, were prepared when different molar ratio of fluoroalkyl iodides and biphenol A was employed.

Probing Target and Designing Nicotinoid Derivatives for Antitumor Leading Compound MED

ZHANG Lian-Ru*, YI Yu-Ting, CHEN Jun-Jie, ZHANG Wei, HUANG Yao-Jian, ZHENG Zhong

2010, 31(6):  1184-1189. 

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Antitumor lead compound mycoepoxydiene(MED) was isolated from marine fungus in the year of 2002, but till now the mechanism of MED against cancer is still unclearly. Heat shock protein 90(Hsp90) has emerged in recent years as a promising new target for anticancer therapies, owing to a lot of tumorigenesis relative client proteins need the help of Hsp90 for folding and keeping stable. The experiment of denatural luciferase renature showed that MED is a potential inhibitor of Hsp90, which stimuli us to perform the research for MED both as a novel inhibitor of Hsp90 and the antitumor leading compound. The nicotinoid derivatives of MED(NDM) was designed based on the structure of MED and the prediction of molecular docking program. MTT assay showed that nicotinoid derivate 4-NDM exhibited antitumor activity against HeLa cells in vitro with IC₅₀ 4.7 μmol/L. The derivate 4-NDM also can induce deregulation of the client protein Akt, Raf-1 and P-Akt, when treated HeLa cell with the compound, just as MED done. Compare with MED, 4-NDM not only showed stronger antitumor activity, but also exhibited higher affinity for Hsp90. The results illustrate that MED and its nicotinoid derivatives may be target for Hsp90 as the inhibitor has antitumor activity.

Effect of Ethanol on the Catalysis of CGTase

WANG Liang, GU Zheng-Biao*, CHENG Li, HONG Yan

2010, 31(6):  1190-1194. 

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UV absorption spectroscopy was used to study the stability constant(K_s) and free energy change(ΔG)of the inclusion reaction of ethanol or cyclohexane with β-cyclodextrin. The K_s and ΔG of ethanol with β-cyclodextrin was 4.71 L/mol and -3.84 kJ/mol; the K_s and ΔG of cyclohexane with β-cyclodextrin was 19.56 L/mol and -7.37 kJ/mol. The binding ability of cyclohexane with β-cyclodextrin is higher than that of ethanol. The effect of ethanol added is shown not to be related to the product inhibition of CGTase, the way of action is different from cyclohexane. Ethanol can not only increase the activities of CGTase, but also inhibit the effect of the coupling reaction and hydrolysis reaction, resulting in an increase in cyclodextrins yield.

Study on Periodic Mesoporous Rh(Ⅰ) Organometallic Catalyst for Water-medium Heck Reaction

HUANG Jian-Lin, YANG Xu-Shi, WANG Mei-Tao, LI He-Xing, ZHANG Fang*

2010, 31(6):  1195-1199. 

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Periodic mesoporous Rh(Ⅰ) organometallic catalyst[Rh(Ⅰ)-PPh₂-PMO(Ph)] was synthesized by coordinating Rh(PPh₃)₃Cl complex with PPh₂-ligand originally incorporated into the phenyl-bridged periodic mesoporous organosilica(PMO) via surfactant-directed co-condensation approach. The Rh(Ⅰ) heterogeneous catalyst were characterized by FTIR, NMR, XRD, TEM and N₂ sorption technologies. This catalyst can be effectively applied in water-medium Heck reaction, which results demonstrated it afforded similar catalytic performance to that of the corresponding homogeneous catalyst. It could be attributed to the large surface area and ordered mesoporous channels of the PMOs support, leading to the high dispersion of Rh(Ⅰ) active sites and the reduced diffusion limit. Meanwhile, the phenyl fragments embedded in the pore walls could enhance surface hydrophobility, which further promoted the diffusion and adsorption of organic molecules, leading to the enhanced activity. Besides, the Rh(Ⅰ)-PPh₂-PMO(Ph) could be used repetitively, showing a good potential in industrial applications.

Preparation and Its Electrocatalytic Properties of Multilayered Composite Films Containing Molybdovanadophosphate and Poly(amidoamine) Dendrimer

SHI Yuan-De, LIN Shen*, XU Hui-Hong, LUO Ming-Hong, ZHENG Si-Ning

2010, 31(6):  1200-1205. 

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Dawson-type molybdovanadophosphate was synthesized and then used for fabricating organic-inorganic multilayer films with a generation-4 poly(amidoamine) dendrimer as an organic spacer on electrode substrate. The multilayer films were characterized by XPS, UV-Vis, CV and AFM. The results show that the multilayer films grow gradually and uniformly, and four redox processes are observed in CV, the formal potentials of the composite films are shifted linearly to negative position at higher pH. The multilayer films electrode is stable and show good electrocatalytic activity toward the reduction of NO₂^-, BrO₃^- and the oxidation of ascorbic acid. The results show a convenient method to obtain the multilayer composite films which have potential applications in the field of electrochemical biosensors and multifunctioanal electrocatlytic materials.

Preparation of TiO₂-pillared HTiNbO₅ and Catalytic Performance in Vapor Phase Beckmann Rearrangement Reaction of Cyclohexanone Oxime

GUO Xian-Ji*, HOU Wen-Hua, LIU Shu-Min, LI Li-Min

2010, 31(6):  1206-1212. 

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A mixture of titanium isopropoxide, acetic acid and deionized water in a volume ratio of 1∶16∶40 generated a solution containing Ti(Ⅳ) polycation species, which was allowed to exchange with alkylammo-nium ions in the interlayers of the n-decylamine-preswelled titanoniobate. This exchange reaction led to the formation of Ti(Ⅳ) polycation-intercalated layered titanoniobate with an interlayer distance of 1.70 nm. The ordered layered structure of the novel material was still retained upon calcination at 623 K. Characterizations of XRD and N₂ adsorption-desorption isotherms indicated that the TiO₂-pillared HTiNbO₅ (abbreviated to TiO₂-HTiNbO₅) obtained by calcination at 723 K in air environment was a porous layered materials with an interlayer distance of 0.97 nm and a BET specific surface area of 89 m²/g. The vapor phase Beckmann rearrangement reaction of cyclohexanone oxime was studied with TiO₂-HTiNbO₅ and B₂O₃/TiO₂-HTiNbO₅ as catalysts. The cyclohexanone oxime conversion and the selectivity for the formation of ε-caprolactam on B₂O₃/TiO₂-HTiNbO₅ were higher than those on TiO₂-HTiNbO₅. The B₂O₃/TiO₂-HTiNbO₅ catalyst with B₂O₃ loading mass fraction of 7.31% exhibited a near-100% conversion of the oxime within 4.5 h and a near 90% selectivity for ε-caprolactam. FTIR spectra indicated that highly dispersed BO₄ species were present in the surface of B₂O₃/TiO₂-HTiNbO₅ with a low B₂O₃ loading; for the B₂O₃/TiO₂-HTiNbO₅ samples with a B₂O₃ loading higher than 7.31%, BO₃ species were dominant. BO₄ and BO₃ species on the surface of TiO₂-HTiNbO₅ showed synergistic promotion effect for vapor-phase Beckmann rea-rrangement reaction of cyclohexanone oxime.

Fabrication and Catalytic Activity of Nickel Core-shell Structure

HAO Wei-Chang*, ZHAI Ting-Ting, WANG Xu, WANG Tian-Min

2010, 31(6):  1213-1217. 

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Nickel has received wide application in industry catalyst field. PS/Ni core-shell structure and Ni nanoparticles were fabricated by soft chemical methods, and SEM, XRD were used to characterize the morphology and structure of samples. The catalytic performances of the PS/Ni and Ni nanoparticles were evaluated using methylene blue as a model reagent. This experiment realized degradation of dye and hydrogen production via NaBH₄ hydrolysis in one step. The results show that the core-shell structure promotes the catalytic activity of nickel. The degradation efficiency of dye and hydrogen production velocity using PS/Ni catalyst is 1.42 and 4.76 times higher than that using Ni nanoparticle catalyst, respectively. The advantage of core-shell structure in catalysis is proved.

Effect of Complex Formation on Resonance Raman Scattering Cross Section of β-Carotene

SUN Cheng-Lin*, ZHANG Xue-Ya, LI Zhan-Long, ZHOU Mi, OUYANG Shun-Li, ....

2010, 31(6):  1218-1221. 

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β-Carotene is the polyenes linear biological molecule, which can form charge transfer complex in iodine solution. We measured the UV-Vis absorption and Raman spectra by the Avaspec-2048-2 spectrophotometer and the micro Raman spectrometer(Renishaw InVia Raman microscope), respectively. The result show that the UV-Vis absorption spectra at 460 nm of β-carotene disappeare in polar solvent 1,2-dichloroethane. And a new, intense absorption band of complex which was formed by β-carotene and iodine was found at 1000 nm. So the resonance Raman spectra of β-carotene in complex couldn′t be observed by 514.5 nm Laser. And Raman cross section of β-caroten that wasn′t in the complex reduced. Due to the solution of β-carotene and iodine was unstable, the molecule structural order of β-caroten weaked, which lead to the weak of coherent weakly damped C-C vibrations, and made the Raman scattering cross section reduced.

Volumetric Properties of Binary Systems of n-Alkane/JP-10

YANG Feng-Jun, GUO Yong-Sheng*, WEI Hui, XING Yan, FANG Wen-Jun, LIN Rui-Sen

2010, 31(6):  1222-1226. 

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The densities and viscosities of the binary mixtures of n-octane/JP-10 and n-decane/JP-10 were determined at 298.15 K by the Anton Paar vibriating-tube densimeter and Ubbelohde viscometer, over the entire composition range. Excess molar volumes, apparent molar volumes, partial molar volumes and the contribution to the excess volume of the components were calculated. The experimental data indicate that the addition of n-alkane has a distinct effect on the density and viscosity of JP-10 and V_m^E of the binary systems are negative.Thermodynamic functions of activation of the binary systems were calculated according to the absolute rate theory approach of Eyring, which indicate ΔS^0≠ plays a major role. Conclusions were qualitatively discussed in terms of molecular interactions, which provide important information on the research and application of JP-10 and blended fuel.

Low-temperature Heat Capacities and Thermochemistry Properties of Ethylene Diamine Dihydrochloride

LIU Yu-Pu, DI You-Ying*, HE Dong-Hua, KONG Yu-Xia, YANG Wei-Wei, DAN Wen-Yan

2010, 31(6):  1227-1230. 

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Ethylene diamine dihydrochloride was synthesized by solvothermal synthesis. X-ray crystallography was applied to characterize its structure. Low-temperature heat capacities of the title compound were measured by a precision automated adiabatic calorimeter over the temperature range from 78 K to 370 K. A polynomial equation of heat capacities as a function of the temperature was fitted by least square method. A reasonable thermochemical cycle was designed on the basis of a designed thermochemical reaction(1.0 mol/L NaOH solution was chosen as the calorimetric solvent), and standard molar enthalpies of dissolution for the reactants and products of the reaction in the selected solvent were measured by an isoperibol solution-reaction calorimeter, respectively. Eventually, the standard molar enthalpy of formation of the title compound was derived to be -(540.74±1.33) kJ/mol by the Hess thermochemical cycle. The reliability of the designed thermochemical cycle was verified by UV-Vis spectroscopy and the data of the refractive indices. The standard molar enthalpy of formation of the title compound is negative with a larger absolute value. The results show that the title compound has lower energy and more stable structure in comparison with the stabile elementary substance.

Microbial Fuel Cell Using Sequential Anode-cathode to Treat Brewery Wastewater

WEN Qing*, WU Ying, WANG Gui-Ling, ZHAO Li-Xin, SUN Qian, KONG Fan-Ying

2010, 31(6):  1231-1234. 

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A sequential anode-cathode double-chamber MFC, in which the effluent of anode chamber was used as a continuous feed for an aerated cathode chamber, was constructed to treat brewery wastewater. The chemical oxygen demand(COD) can also be removed by heterotrophic bacteria in the cathode chamber. The performances of electricity generation and brewery wastewater treatment were studied. The results showed that the sequential anode-cathode MFC had a great potential for substrate removal in both anode and cathode. Total COD removal efficiency of 92.2%—95.1% was achieved, with COD removal efficiency of 47.6%—56.5% in anode chamber. The open circuit voltage of the MFC is 0.451 V and the maximum power output is 2.89 W/m³. According to electrode potential measurement and electrochemical impedance spectroscopy, the key limited factor was polarization loss of cathode. The performance of MFC can be optimized by decreasing COD of cathode chamber, using more superior cathode materials, increasing oxygen concentration etc.

Properties of H₂ Adsorption on the Alkali-metal-doped Carbon Nanotube

CHEN Yuan-Mei, LI Qing, HUANG Yuan-He*

2010, 31(6):  1235-1239. 

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The H₂ adsorption on the alkali-metal-doped armchair single-walled carbon nanotube was investigated using density functional theory(DFT) with full geometric optimization. The alkali metal doping both inside and outside the tube are considered. The calculations show that the electrons are transferred from the doped alkali-metal atoms to the carbon nanotube. Compared with the alkali-metal atom doping into the tube inside, the doping of alkali-metal atoms on the wall outside is more favorable to the H₂ adsorption. It is found that the coordination interaction between the H₂ and the nanotube exists in the most stable structure for the H₂ adsorption.

Theoretical Study on the Mechanism and Dynamic of CF₃CH₂CH₃ Reaction with OH Radicals

WANG Yong-Xia, GAO Hong, WANG Qin, LIU Jing-Yao*

2010, 31(6):  1240-1245. 

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The optimized geometries and frequencies of all the stationary points involved in each reaction channel of the CF₃CH₂CH₃+OH reaction were calculated at the BB1K/6-31+G(d,p) level, and the potential energy profile is further refined by single-point energy calculations at the BMC-CCSD, MC-QCISD and G3(MP2) levels. The rate constants of all channels were evaluated by variational transition state theory(VTST) at the BMC-CCSD//BB1K, MC-QCISD//BB1K, G3(MP2)//BB1K and BB1K levels over a wide temperature range of 200—1000 K, and the contribution of H-abstraction from the —CH₂ and —CH₃ groups to the total reaction was discussed. The present calculations show that the rate constants evaluated at the BMC-CCSD//BB1K level are in excellent agreement with the available experimental values in the measured tempe-rature range. Finally, the three-parameter rate-temperature expression of the total reaction over the whole temperature range 200—1000 K was given as k=1.90×10^-21T^3.21exp(-292.62/T).

Theoretical Study on the Properties of CO and CH₃O Adsorption on Cu₂O(111) Surface and Co-adsorption

ZHANG Ri-Guang, ZHENG Hua-Yan, WANG Bao-Jun, LI Zhong*

2010, 31(6):  1246-1251. 

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Based on density functional theory in the generalized gradient approximation, together with periodic slab model, CO and CH₃O adsorption and co-adsorption on Cu₂O(111) non-polar surface were systematically investigated. Four molecular orientations of CO and O-down orientation of CH₃O over different adsorption sites, Cu_CUS, Cu_CSA, O_SUF and O_SUB of the Cu₂O(111) surface were considered. The adsorption energy, geometrical parameter and Mulliken charge indicate that Cu_CUS is the active site for CO adsorption, Cu_CSA is the active site for CH₃O adsorption. CO and CH₃O adsorption mode improves the relaxation of Cu₂O(111) surface. In co-adsorption system, the interaction between CO and CH₃O is 75.89 kJ/mol, which help to product CH₃OCO, the calculated results are in agreement with experimental facts.

Microspheres Prepared from Ultrahigh Molecular Weight Polyethylene in Supercritical CO₂ Fluid

WANG Chang-Ming, ZHANG Xiu-Qin, ZHAO Ying, HAN Bu-Xing, WANG Du-Jin*

2010, 31(6):  1252-1256. 

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The hollow microspheres were prepared from ultrahigh molecular weight polyethylene(UHMWPE) in supercritical CO₂ fluid. The sphere size is Gaussian distribution, and can be controlled at a narrow range. There are pores on the surface of hollow microspheres due to the CO₂ gas releasing from confined location in the microsphere with decreasing the temperature of supercritical fluid. The crystallinity increases and monoclinic crystals can be generated for prepared UHMWPE microspheres in supercritical CO₂ fluid. The isothermal crystallization process can increase both the crystallinity and the content of orthorhombic crystals of UHMWPE.

Copolymerization of β-Pinene and Norbornene with 2-Aminopyridine Nickel(Ⅱ) Complexes/MAO Catalysts

HUANG Zeng-Fang, GAO Hai-Yang, WU Qing*

2010, 31(6):  1257-1262. 

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In the presence of methylaluminoxane(MAO), 2-aminopyridine Ni(Ⅱ) complexes [(2-PyCH₂NAr)NiBr, Ar=2,6-dimethylphenyl(a), 2,6- diisopropylphenyl(b), 2,6-difluorophenyl(c)] presented highly catalytic activity for the copolymerizations of β-pinene and norbornene and afforded the copolymers with broad molecular weight distribution(PDI≈3.7—5.5). Complex c exhibited highest catalytic activity for the copolymerization under same conditions.After being extracted by CHCl₃ and THF, the crude product could be divided into two fractions with narrow molecular weight distribution(PDI≈2.0), CHCl₃-soluble but THF-insoluble fraction and THF-soluble fraction. The former contains high norbornene content(x_N＞90%) with higher molecular weight and the latter contains high β-pinene content with lower molecular weight, indicating that there exist two kinds of catalytic species in the copolymerization systems. The TGA analyses of the copolymers show that there are two thermal decomposition stages, and the loss of mass in the low thermal decomposition temperature stage decreases with an increase of norbornene content in the copolymer.

Thermal and Electrical Conductivities of the Graphitized Carbon Nanotube/poly(methyl methacrylate) Composites Based on Weak Nanotube-polymer Interactions

ZENG You*, ZHAO Long, LIU Peng-Fei, DU Jin-Hong, LIU Chang

2010, 31(6):  1263-1267. 

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Electrical and thermal conductivities of carbon nanotube(CNT)/polymer composites are greatly hindered by polymer-wrapping around CNTs due to high surface energy of CNTs. The graphitized multi-walled CNTs filled poly(methyl methacrylate)(PMMA) were investigated on the basis of surface physical chemistry and wetting thermodynamics. The electrical and thermal conductivities of the graphitized CNT/PMMA compo-sites were measured to evaluate enhancing effects of the graphitized CNTs. The graphitized CNT/PMMA composites exhibit high electrical conductivity and a low percolation threshold of is 0.8%(mass fraction), and the thermal conductivity of the composites with 3%(mass fraction) increases by 193% in comparison with that of the neat PMMA, which is due to the integrated microstructures of the graphitized CNTs, weak CNT-PMMA interactions, low contact resistance between CNTs, and efficient conducting CNT-networks. We suggest that high-performance composites can be designed and fabricated by fully considering the surface energy of components and the filler-polymer interactions.

Surface and Antibacterial Properties of Polyurethane with Fluorinated Bis-ammonium Salts Attached to Hard Segments

LUO Jian-Bin*, MA Chen, LIAO Rong, WAN Jing, ZHANG Peng, ZHANG Jie

2010, 31(6):  1268-1273. 

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The surface properties of the novel polyurethanes with fluorinated bis-ammonium salts group(FQPUs) were studied by contact angle test and XPS test. For polyurethanes with pendant fluorinated bis-ammonium salts, addition of little fluorinated bis-ammonium salts chain extender(EDF) made the polyurethane surface saturated with ammonium salts and fluorinated chains. The fluorinated alkyl chains endowed polyurethane with very low surface energy and antibacterial adhesion properties as proven by surface free energy test. Water contact angle demonstrated that the fluorinated chains could not overturn and the antibacterial adhesion properties of polyurethane would be maintained. Moreover, this properties can make polyurethane with lower water adsorption. It was found by plate count that polyurethanes with fluorinated bis-ammonium salts chain extender(EDF)(FQPUs) all had excellent antibacterial properties against gram positive bacteria, i.e. S. aureus and a little lower antibacterial properties against gram-negative bacteria, i.e. E. coli.

Effect of Self-nucleation Process on Isothermal Crystallization Behavior of Polybutylene Succinate

LUO Fa-Liang, ZHANG Xiu-Qin, LI Rong-Bo, GAN Zhi-Hua, JI Jun-Hui, WANG Du-Jin

2010, 31(6):  1274-1279. 

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Self-seeding nucleation technique can improve the nucleation efficiency of semi-crystalline polymers, reduce the crystal particle size and improve polymer performance. The appropriate temperature scope of self-seeding nucleation, the effect of self-seeding nucleation on crystallization and subsequent melting behavior of bio-degradable poly(butylenes succinate)(PBS)were studied by DSC. The results show that the suitable temperatures of self-seeding nucleation for PBS are scope of 118 ℃ to 120 ℃. The crystallization temperature of PBS increases obviously(about 20 ℃) after suffered the self-seeding nucleation process. Isothermal crystallization in the range of temperature between 100 ℃ and 104 ℃ after melting for 5min at 118 ℃ were investigated, and the isothermal crystallization kinetics were analyzed by Avrami equation. The results suggest that the Avrami equation also can be applied to analysis the isothermal crystallization process of self-seeding nucleation PBS samples and the relative parameters including K and n were calculated. The n value is high closing to 6, which results from the increasing of the growth point in crystal nucleus. The melting processes after isothermal crystallization were analyzed and the equivalent melting point of PBS was discussed by Hoffman-Weeks Equation. Multiple melting peaks can also be found on the heating DSC curves and there is no effect of the self-seeding nucleation process on equivalent melting point of PBS. Additionally, based on Arrhenius equation, the isothermal crystallization active energy of self-seeding nucleation PBS was calculated and the value was -286 kJ/mol.

Synthesis, Self-assembly and Gene Transfection Hyperbranched Polyethylenimine-poly(β-benzyl-L-aspartate) Copolymer

JIAO Yong-Hua, ZHOU Jun, LI Yan, ZHANG Kai, FU Yu*

2010, 31(6):  1280-1284. 

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A novel amphiphilic and biodegradable copolymer of hyperbranched polyethylenimine-poly(β-benzyl-L-aspartate)(PEI-PBLA) was synthesized by ring opening polymerization of the N-carboxyanhydride of β-benzyl-L-aspartate(BLA-NCA) with hyperbranched polyethylenimine(PEI) as initiator and characterized by ¹H NMR. PEI-PBLA copolymers could form micelles in both organic solvent and water. The micelle formation of PEI-PBLA in CH₂Cl₂ was displayed by extraction of methyl orange indicator from aqueous solutions. As for PEI-PBLA micelle in water, the critical micelle concentration(cmc) was determined by fluorescence probe method and corresponding morphology was observed by TEM. Meanwhile, the complexation of PEI-PBLA with DNA was explored by gel retardation. The studies imply that PEI-PBLA has great potential in many applications, such as drug delivery, gene transfection and so on.