共查询到19条相似文献,搜索用时 140 毫秒
1.
再生丝素和聚乙烯醇混合膜的结构,性能及其葡萄糖传感器… 总被引:3,自引:0,他引:3
用扫描电镜分析了再生丝素(RSF)和聚乙烯醇(PVA)混合膜的形貌结构,并测定了其吸水性和机械强度,用RSF和PVA的混合材料把葡萄糖氧化酶固定在玻碳电极表面,制成电流型葡萄糖传感器。以1,4-苯醌为电子传递体,酶电极对葡萄糖有灵敏的响应,峰电流的增加与葡萄糖的浓度在10^-5-10^-2mol/L范围内良好的线性关系。用此方法制成的葡萄糖传感器物理性能好,其有效寿命长达2个月以上,该酶电极对葡萄 相似文献
2.
以N—甲基吩嗪硫酸盐为电子传递体的过氧化氢传感器 总被引:3,自引:0,他引:3
用再生丝素把过氧化物酶(POD)固定在玻碳电极表面,以N-甲基吩嗪硫酸盐(PMS)为电子传递体,制成过氧化氢传感器,因该酸电极对过氧化氢(H2O2)有良好的催化响应,PMS还原电流的增值与过氧化氢的浓度在10^-6-10^-3mol/L范围内有良好的线性关系,酶电极稳定性好,灵敏度高,对过氧化氢的响应时间小于10s,其有效寿命可达二个月以上。用扫描电镜和红外光谱观察和分析了POD和再生丝素共混膜的 相似文献
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纳米颗粒增强的葡萄糖生物传感器 总被引:36,自引:1,他引:35
研制的纳米增强葡萄糖传感器是用纳米憎水Au颗粒。亲水Au颗粒、憎水SiO_2颗粒以及Au和-SiO_2颗粒混合与聚乙烯醇缩丁醛(PVB)构成复合固酶膜基质,用溶胶-凝胶法固定葡萄糖氧化酶(GOD),组成葡萄糖生物传感器.实验表明,纳米颗粒可以大幅度提高固定化酶的催化活性,响应电流从相应浓度的几十纳安增强到几千纳安,电极响应迅速, 1min达到稳态,探讨了纳米颗粒效应在固定化酶中所起的作用,开辟了制备直接电子传递第三代生物传感器的新途径和纳米颗粒应用的新领域。 相似文献
4.
磷钼杂多酸-L-半胱氨酸自组装超分子膜电极对亚硝酸根电催化还原的研究 总被引:5,自引:0,他引:5
制备了磷钼杂多酸-L-半胱氨酸自组装超分子膜电极(P2Mo18-L-Cys/Au)。采用水平衰减全反射(ATR-FTIR)光谱表征了膜的组成。研究了该膜电极的电化学性质,发现它在1.0 mol/L H2SO4溶液中,于0.0~0.7V(vs.SCE)间CV扫描出现两对稳定、可逆的氧化还原峰,其中峰电位分别为Em1=0.334 V,Em2=0.188V,对应着P2Mo18O_(62)~(6-)的两步2电子-2质子反应;计时库仑法计算了薄膜内的电子传递系数D为5.01 × 10~(-8)cm2·s~(-1)。该膜电极对酸性溶液中的NO_2~-有明显的电催化还原作用,初步探讨了电催化机理。用差分脉冲伏安法(DPV)测定其还原峰电流与NO_2~-的浓度在2.0 ×10~(-6)~2.0 × 10~(-4)mol/L范围内呈良好的线性关系,相关系数为0.9953,检测限5.0×10~(-7)mol/L。该电极用于模拟水样中NO_2~-的测定,结果满意。 相似文献
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邻苯二胺—过氧化氢—辣根过氧化物酶酶联免疫示差脉冲伏安法测定人血清… 总被引:5,自引:3,他引:5
建立了邻苯二胺(OPD)-H2O2-辣根过氧化物酶(HRP)酶联示差脉冲伏安分析体系并用于测定人血清中类风湿因子(RF),HRP催化H2O2氧化OPD所形成麦催化产物在PH2.0磷酸盐-枸椽酸缓冲溶液中于-0.18V左右产生-灵敏示差脉冲伏安峰,在RF浓度在1.25-20.0U/mL之间与峰电流呈线性关系,应用此峰检测人血清RF的检测限低至0.28U/mL。该法较相同条件下ELISA以光度测定法的 相似文献
7.
邻苯二胺-过氧化氢-辣根过氧化物酶酶联免疫示差脉冲伏安法测定人血清类风湿因子抗体 总被引:1,自引:0,他引:1
建立了邻苯二胺(OPD)-H2O2-辣根过氧化物酶(HRP)酶联示差脉冲伏安分析体系并用于测定人血清中类风湿因子(RF),HRP催化H2O2氧化OPD所形成酶催化产物在pH2.0磷酸盐-枸橼酸缓冲溶液中于-0.18 V左右产生一灵敏示差脉冲伏安峰,RF浓度在1.25~20.0 U/mL之间与峰电流呈线性关系,应用此峰检测人血清RF的检测限低至 0.28U/mL。该法较相同条件下ELISA显色光度测定法的灵敏度增加5倍,且受干扰较少。 相似文献
8.
纳米级金膜微电极的制作,表征及异相催化反应 总被引:1,自引:0,他引:1
报道了纳米级金膜微电极的制作方法,用XPS及SEM对电极表面进行了表征,考察了该电极的循环伏安及计时电流特性,在聚吡咯修饰微带金电极上成功地实现了葡萄糖氧化酶和电子传递媒体Fe(CN)6^3-的同时固定,并研究了GOD/Fe(CN)6^3-/PPy微酶电极对葡萄糖的响应,稳态响应电流与葡萄糖浓度之间存在Michealis-Menten动力学特征。 相似文献
9.
葡萄糖脱氢酶微型生物传感器的研制及应用 总被引:3,自引:0,他引:3
以甲苯胺兰(TB)修饰碳糊微电极为基体,将葡萄糖脱氢酶(GDH)用丝素蛋白膜固定于修饰微电极表面制成了生物传感器,在pH7.0的NaOH-NaH2PO4缓冲溶液中,烟酰胺腺嘌呤二核苷酸(NAD)的浓度为1.04×10^-3mol/L的条件下,其响应电流与葡萄糖浓度在1.0×10^-4~3.2×10^-3mol/L范围内有良好线性关系,响应时间为20s;检测限为4.0×10^-5mol/L。该传感器 相似文献
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Yongcheng Liu Xin Chen Jianghong Qian Haiying Liu Zhengzhong Shao Jiaqi Deng Tongyin Yu 《Applied biochemistry and biotechnology》1997,62(2-3):105-117
The structure and properties of the blend of regenerated silk fibroin (RSF) and poly(vinyl alcohol) (PVA) were investigated.
The two polymers in the blend are in the state of phase segregation. Infrared (IR) spectra indicate that the RSF in the blend
maintains its intrinsic properties, thus, ethanol treatment can transfer silk I structure of RSF to silk II structure. The
water absorption property and mechanical property of the blend are improved in comparison with those of RSF. The blend maintains
the major merit of RSF, that is, it can immobilize glucose oxidase on the basis of the conformational transition from silk
I structure to silk II structure. The properties of the immobilized enzyme are examined. Moreover, the second generation of
glucose sensor based on the immobilized enzyme is fabricated and it has a variety of advantages including easy maintenance
of enzyme, simplicity of construction, fast response time and high stability. 相似文献
12.
再生丝素固定葡萄糖氧化酶及其传感器应用 总被引:7,自引:0,他引:7
再生丝素固定葡萄糖氧化酶及其传感器应用钱江红,刘永成,刘海鹰,于同隐,邓家祺(复旦大学化学系高分子科学系,上海,200433)关键词再生丝素,葡萄糖氧化酶,传感器,酶电极酶电报的各项性能在很大程度上取决于酶的固定比方法,葡萄糖氧化酶的固定化方法很多1... 相似文献
13.
Regenerated silk fibroin prepared from waste silk was employed as immobilization matrix for peroxidase and the structures of the blend membranes of regenerated silk fibroin and peroxidase were first investigated with IR and scanning electron microscopy. There was intermolecular interaction between peroxidase and regenerated silk fibroin in the immiscible state. Cyclic voltammetry and constant applied potential measurement showed that Methylene Green efficiently mediated electron transfer from oxidized horseradish peroxidase in regenerated silk fibroin membrane to a glassy carbon electrode. A sensor coupling immobilized peroxidase with Methylene Green responded rapidly to low H(2)O(2) concentration and achieved 95% of the steady-state current in less than 25 s with a detection limit of 1.0 x 10(-7) M H(2)O(2). The sensor was stable in continuous operation, indicating that peroxidase was entrapped in regenerated silk fibroin membrane and did not freely diffuse away from the sensor surface into solutions. 相似文献
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H. Liu Huihong Deng Kang Sun Deyao Qi Jiaqi Deng Yongcheng Liu Tongyin Yu 《Analytical and bioanalytical chemistry》1997,357(7):812-816
Porous composite membranes of regenerated silk fibroin and poly(vinyl alcohol) were prepared by adding polyethyleneglycol
to the composite solution to reduce the mass-transfer resistance to the diffusion of substrate material transport; their surfaces
were visualized with scanning electron microscopy. An amperometric glucose biosensor employing Meldola blue dispersed in polyester
ionomer as electron transfer mediator was prepared to test the feasibility and workability of the composite membrane as immobilization
matrix for glucose oxidase. The cationic exchange property of the polyester ionomer was employed to provide high local concentrations
of Meldola blue (MB+) in the polymer film via ion exchange. Performance and characteristics of the glucose biosensor were evaluated with respect
to response time, detection limit, applied potential, thickness of polyester ionomer membrane, pH and temperature. The glucose
biosensor possesses a variety of advantages including easy maintenance of enzyme, simplicity of construction, fast response
time and high stability.
Received: 13 May 1996 / Revised: 30 July 1996 / Accepted: 2 August 1996 相似文献
16.
Two enzmyes, glucose oxidase and peroxidase, were for the first time simultaneously immobilized in regenerated silk fibroin membrane. The structure and morphology of the regenerated silk fibroin membrane containing both glucose oxidase and peroxidase were investigated with IR spectra and SEM. The bienzymes do not change the structures of the regenerated silk fibroin in the membrane, which has an islands-sea structure. For the first time, an amperometric methylene green mediating sensor for glucose based on co-immobilization of both glucose oxidase and peroxidase in regenerated silk fibroin was constructed. Cyclic voltammetry and amperometry were used to test the suitability of methylene green shuttling electrons between peroxidase and the glassy carbon electrode. The bienzyme-based system offers fast response and high sensitivity of the sensor to glucose. The effects of pH, temperature, and the concentration of the mediator on the response current were evaluated, and the dependence of the Michaelis-Menten constant K(m)(app) on the concentration of the mediator was investigated. 相似文献
17.
《Analytical letters》2012,45(9):1593-1609
Abstract Regenerated silk fibroin was successfully used to immobilize glucose oxidase and the structure of the blend membrane was investigated. The molecules of glucose oxidase in the membrane were in aggregates. Glucose sensor was fabricated by coupling the blend membranes with Clark electrode. Its kinetic constants such as apparent Michael's constants Km app, maximal current response ΔSmax and apparent activation energies Ea of the reaction, effects of pH, temperature and ethanol on the sensor were examined. 相似文献
18.
Yongcheng Liu Haiying Liu Jianghong Qian Jiaqi Deng Tongyin Yu 《Fresenius' Journal of Analytical Chemistry》1996,355(1):78-82
Two enzmyes, glucose oxidase and peroxidase, were for the first time simultaneously immobilized in regenerated silk fibroin membrane. The structure and morphology of the regenerated silk fibroin membrane containing both glucose oxidase and peroxidase were investigated with IR spectra and SEM. The bienzymes do not change the structures of the regenerated silk fibroin in the membrane, which has an islands-sea structure. For the first time, an amperometric methylene green mediating sensor for glucose based on co-immobilization of both glucose oxidase and peroxidase in regenerated silk fibroin was constructed. Cyclic voltammetry and amperometry were used to test the suitability of methylene green shuttling electrons between peroxidase and the glassy carbon electrode. The bienzyme-based system offers fast response and high sensitivity of the sensor to glucose. The effects of pH, temperature, and the concentration of the mediator on the response current were evaluated, and the dependence of the Michaelis-Menten constant Kmapp on the concentration of the mediator was investigated. 相似文献
19.
Masuhiro Tsukada Yoko Gotoh Masanobu Nagura Norihiko Minoura Nobutami Kasai Giuliano Freddi 《Journal of Polymer Science.Polymer Physics》1994,32(5):961-968
Structural changes of native and regenerated silk fibroin membranes were induced by immersion in water-methanol solutions and examined as a function of immersion time and methanol concentration. X-ray diffractometry and infrared spectroscopy data showed that transition from random coil to β-sheet structure occurred favorably when both native and regenerated silk fibroin membranes were immersed in water-methanol solutions, regardless of the different immersion time. Only native silk membrane, treated for 2 min with pure methanol, maintained its original amorphous structure, as demonstrated by differential scanning calorimetric (DSC) curves. The degree of displacement, measured by thermomechanical analysis (TMA), was much greater for regenerated than for native silk fibroin membranes. SDS-PAGE pattern showed that native silk fibroin has a molecular weight of 350, while the regenerated sample is formed by a large number of polypeptides in the range of 200-50 KD. The amount of acidic and basic amino acids decreased slightly in regenerated silk fibroin. Physical properties of silk membranes treated with water-methanol solutions are discussed in terms of membrane structure, treatment conditions, and chemical structure of starting material. © 1994 John Wiley & Sons, Inc. 相似文献