检索结果-南通市图书馆

Journal of Wuhan University of Technology(Materials Science) 2006年第4期21卷 95-98页

作者：贲亚琍刘德立 College of Life Science HuaZhong Normal University Wuhan 430079 ChinaJianghan University Wuhan 430016 China College of Life Science HuaZhong Normal University Wuhan 430079 China

The difference of sensitivity to indole- 3-acetic acid （ IAA ） combined with horseradish peroxidase （HRP） in K562 and BXPC- 3 cells was investigated. The cell proliferation was determined by MTF assay. The cell cycle and apoptosis of K562 and BXPC-3 cells were examined by a fluorescence flow cytometer （FCM） and terminal deoxynacleotidyl transferase-mediated dUTP nick-end labeling （TUNEL） respectively. The experimental results show that IAA and HRP could inhibit BXPC- 3 cell proliferation greatly compared with K562 cell during the first 48 h . The cell cycle was arrested predominantly at G2/ M phase in K562 and BXPC- 3 cells. The cell apoptosis of K562 and BXPC- 3 was induced by IAA/ HRP. There was a significant difference between the two cell lines since BXPC-3 cells were more sensitive than K562 cells by treatments with combination of IAA and HRP.

关键词： indole- 3-acetic acids horseradish peroxidase BXPC- 3 cell K562 cell apoptosis

Effect of Tetrabutylammonium Bromide on Enzymatic Polymerization of Phenol Catalyzed by horseradish peroxidase

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2014年第7期32卷 906-913页

作者： Hua Duan Ke Zheng 崔元臣 Yu-dong Li Lei Zhang Key Laboratory of Ministry of Education for Special Functional Materials Henan University College of Chemistry and Chemical Engineering Henan University

In this article tetrabutylammonium bromide （TBAB） was first added in buffer to compose a convenient and environmentally friendly system, and enzymatic polymerization of phenol catalyzed by horseradish peroxidase （HRP） could proceed efficiently in this system. When TBAB was added, the most conversion of phenol could reach 99.1%. The phenol polymer was considered to consist of a mixture of phenylene （Ph） and oxyphenylene （Ox） units by IR analysis, and the ratio of phenylene to oxyphenylene units （Ph/Ox） was measured by titration. Moreover, the effects of the dosage of horseradish peroxidase （HRP） and pH value on the conversion of phenol were investigated. The reaction performed very effectively in this novel system when the addition of HRP was only 0.2 mg. In all cases, the weight-average molecular weight calculated by GPC-SLS was in a range from 12000 Da to 30000 Da. The phenol polymer prepared in the present research possessed good thermal stability shown by TG analysis.

关键词： horseradish peroxidase Phenol Polymerization Tetrabutylammonium bromide.

Effects of different valences of cerium ion on conformation of horseradish peroxidase

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2008年第6期26卷 857-863页

作者：相丽葛志强 Education Ministry Key Laboratory of Systems Bioengineering College of Chemical Engineering and Technology Tianjin University

Our previous studies demonstrated that Ce^4＋could induce reactive oxygen species （ROS） burst as a signal to promote pacilitaxel biosynthesis in suspension cultured Taxus cuspidate cells. To further understand the mechanism of cerium ions inducing ROS burst, circular dichroism （CD）, synchronous fluorescence, and electron paramagnetic resonance （EPR） were used to detect them inducing conformational change of horseradish peroxidase （HRP）. horseradish peroxidase activity was reduced by 78% by 0.1 mmol/L Ce^4＋, whereas it was only reduced by 28% by 0.1 mmol/L Ce^3＋. Circular dichroism spectra showed that the percentage of transition from helical content and other structure to β strands and flturns was 23.1 when induced by Ce^4＋, whereas it was only 13.2 when induced by Ce^3＋. In synchronous fluorescence spectra, Ce^4＋ led to red shift and intensity-elevation of tryptophan fluorescence emission maximum, whereas in the case of Ce^3＋, the results were a contrast to the above. Furthermore, g factor （gx and gy） in electron paramagnetic resonance （EPR） induced by Ce^4＋ and Ce^3＋ was significantly different. These results indicated that the different valence of cerium ion induced various conformations of HRP, and Ce^4＋ was more effective than Ce^3＋. This suggested that Ce^4＋ affected the burst of ROS through changing the conformation of oxidoreductase.

关键词： cerium conformation horseradish peroxidase heme rare earths

A Chemiluminescence Optical Fiber Glucose Biosensor Based on Co-immobilizing Glucose Oxidase and horseradish peroxidase in a Sol-gel Film

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2002年第1期18卷 12-15页

作者： LI Ying-xiu, ZHU Lian-de and ZHU Guo-yi State Key Lab of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P.R. ChinaZHAO Chun College of Chemistry, Jilin University, Changchun 130023, P Chinese Acad Sci Changchun Inst Appl Chem Electroanalyt Chem Lab Changchun 130022 Peoples R China Jilin Univ Coll Chem Changchun 130023 Peoples R China

An optical fiber bienzyme sensor based on the luminol chemiluminescent reaction was developed and demonstrated to be sensitive to glucose. Glucose oxidase(GOD) and horseradish peroxidase(HRP) were co-immobilized by microencapsulation in a sol-gel film derived from tetraethyl orthosilicate(TEOS). The calibration plots for glucose were established by the optical fiber glucose sensor fabricated by attaching the bienzyme silica gel onto the glass window of the fiber bundle. The linear range was 0 2-2 mmol/L and the detection limit was approximately 0 12 mmol/L. The relative standard deviation was 5.3% ( n =6). The proposed biosensor was applied to glucose assay in ofloxacin injection successfully.

关键词： Fiber optical biosensor Sol-gel Chemiluminescence Glucose oxidase horseradish peroxidase Glucose assay

A novel application of horseradish peroxidase:Oxidation of alcohol ethoxylate to alkylether carboxylic acid

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2008年第12期19卷 1411-1414页

作者： Li Fei Zhi Qiu Xiao Li Yun Ling Li China Research Institute of Daily Chemical Industry Taiyuan 030001 China

A novel application of horseradish peroxidase （HRP） in the oxidation of alcohol ethoxylate to alkylether carboxylic acid in the present of H2O2 was reported in this paper. We propose the mechanism for the catalytic oxidation reaction is that the hydrogen transfers from the substrate to the ferryl oxygen to form the α-hydroxy carbon radical intermediate. The reaction offers a new approach for further research structure and catalytic mechanism of HRP and production of alkylether carboxylic acid.

关键词： horseradish peroxidase Alcohol ethoxylate Alkylether carboxylic acid

Methylene green-mediated sensor highly sensitive to hydrogen peroxide based on entrapment of horseradish peroxidase in composite membrane of regenerated silk fibroin and poly(vinyl alcohol)

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 1996年第4期14卷 359-366页

作者： Wu, YX Liu, HY Qi, DY Liu, YC Qian, JH Liu, SH Yu, TY Deng, JQ SHANGHAI UNIV DEPT CHEM & CHEM ENGNSHANGHAI 200072PEOPLES R CHINA FUDAN UNIV DEPT MACROMOL SCI & CHEMSHANGHAI 200433PEOPLES R CHINA

A novel composite membrane of poly(vinyl alcohol) and regenerated silk fibroin was employed to immobilize horseradish peroxidase (HRP) and IR was used to give a useful insight into the structure of the composite membrane before and after ethanol treatment. A methylene green-mediated sensor sensitive to hydrogen peroxide was fabricated, based on the composite membrane as immobilization matrix for HRP. Cyclic voltammetry and amperometric measurement were for the first time utilized to demonstrate the suitability of methylene green as an electron transfer mediator between immobilized HRP and a glassy carbon electrode in bioelectrocatalytic reduction of hydrogen peroxide. Performance and characteristics of the sensor were evaluated in respect to response time, detection limit, applied potential and concentration of the mediator. The sensor possesses a variety of characteristics including good sensitivity, rapid response time and low detection of limit of 0.1 mu mol/L.

关键词： sensor poly(vinyl alcohol) regenerated silk fibroin methylene green horseradish peroxidase hydrogen peroxide

Development of an Amperometric Hydrogen Peroxide Biosensor based on the Immobilization of horseradish peroxidase onto Nickel Ferrite Nanoparticle-Chitosan Composite

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2011年第2期3卷 91-98页

作者： Furkan Yalcner Emre Cevik Mehmet Senel Abdulhadi Baykal Department of Chemistry Faculty of Arts and SciencesFatih University

Nickel ferrite(NiFe_2O_4) nanoparticles have been dispersed in chitosan solution in order to fab ricate nanocomposite *** peroxidase(HRP) has been immobilized onto this chitosan NiFe_2O_4 nanocomposite film via physical *** size of the NiFe_2O_4 nanoparticles has been estimated us ing X ray diffraction pattern and scanning electron microscopy(SEM) to be 40±9 *** chitosan NiFe_2O_4 nanocomposite film and HRP/chitosan NiFe_2O_4 bioelectrode have been characterized using SEM *** HRP/chitosan NiFe_2O_4 nanocomposite bioelectrode has a response time of 4 s,linearity as 0.3 to 12 m M of H2O2,sensitivity as 22 n A/m *** effects of p H and the temperature of the immobilized HRP electrode have also been studied.

关键词： Biosensor NiFe_2O_4 horseradish peroxidase Nanoparticle Chitosan

Direct Electrochemistry of horseradish peroxidase Immobilized in a Low Molecular Weight Gel

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2014年第3期32卷 263-268页

作者： Yan Hu Yanwen Sun Lu Lu Xirong Huang Key Laboratory of Colloid&Interface Chemistry of the Education Ministry of China Shandong UniversityJinanShandong 250100China

The ternary system of dodecylpyridinium bromide(DDPB)/acetone/H2O with appropriate composition can form a gel spontaneously and the gel is stable in hydrophobic ionic liquid 1-butyl-3-methylimidazolium hexafluorophos-phate([Bmim]PF_(6)).Based on the gelation phenomenon we observed,the low molecular weight gelator(LMWG)was first tried to immobilize horseradish peroxidase(HRP)on glassy carbon electrode(GCE).The scanning elec-tron microscope(SEM)images,the UV-Vis spectra and the bioactivity measurement indicate that the gel is suitable for the immobilization of *** direct electrochemistry of the HRP-gel modified GCE(HRP-gel/GCE)in[Bmim]PF_(6)shows a pair of well-defined and quasi-reversible redox peaks with the heterogeneous electron transfer rate constant(ks)being 14.4 s^(−1),indicating that the direct electron transfer between HRP and GCE is *** HRP-gel/GCE is stable and *** the electrode exhibits good electrocatalytic effect on the reduction of trichloroacetic acid(TCA),showing good promise in bioelectrocatalysis.

关键词： low molecular weight gelator horseradish peroxidase electron transfer bioelectrocatalysis biosensors

Tetra-substituted Amino Aluminum Phthalocyanine as a New Red-region Fluorescent Substrate for horseradish peroxidase Based Enzyme-linked Immunosorbent Assay

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2002年第12期20卷 1573-1578,1463页

作者：杨黄浩李东辉陈小兰曲会英丁马太许金钩 Key Laboratory of Analytical Science of Ministry of Education Department of Chemistry Xiamen University Xiamen Fujian 361005 China Department of Material Science Xiamen University Xiamen Fujian 361005 China Cancer Research Center Xiamen University Xiamen Fujian 361005 China Email: Jin-Gou Xu (jgxu@***)

The use of tetra-substituted ammo aluminum phthalocyanine (TAAIPc) as a new red-region fluorescent substrate for horseradish peroxidase (HRP)-based enzyme-linked immunosorbent assay was investigated. TAAIPc displayed an excitation maximum at 610 nm and emission maximum at 678 nm in a strong acidic medium. In the presence of HRP, trace amounts of H2O2 could rapidly and significantly react with TAAIPc, thus quenching the fluorescence of TAAIPc. The Michaelis-Menten parameters Km and Vmax were measured to be 2.82 × 10?6 mol/L?1 and 6.0 × 10?9 mol·L?1, respectively. In this paper, TAAIPc was used in an HRP-based enzyme-linked immunosorbent assay (ELISA) of α-fetoprotein (AFP) in human serum with satisfactory results. AFP could be determined in the concentration range of 0.5–200 ng/mL with a detection limit of 0.2 ng/mL, which was close to that of radioimmunoassay. The advantage of proposed method was strongly minimizing the interference resulting from background fluorescence or scattering light and had a high analytical sensitivity.

关键词： tetra-substituted amino aluminum phthalocyanine red-region fluorescent substrate horseradish peroxidase enzyme-linked immunosorbent assay

Direct Electrochemical Reaction of horseradish peroxidase Immobilized on the Surface of Active Carbon Powders

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2004年第4期15卷 453-454页

作者： DongMeiSUN ChenXinCAI WeiXING TianHongLU ChangchunInstituteofAppliedChemistry ChineseAcademyofSciencesChangchun130022 DepartmentofChemistry NanjingNormalUniversityNanjing210097

It is reported for the first time that horseradish peroxidase (HRP) immobilized on the active carbon can undergo a direct quasi-reversible electrochemical reaction. In addition, the immobilized HRP showed the stable b... 详细信息

关键词： Direct electrochemical reaction horseradish peroxidase active carbon.