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利用磁性纳米Fe3O4和CdTe/CdS量子点结合Nafion的良好成膜性,将肌红蛋白(Mb)固定在玻碳电极表面制备成Nafion/Fe3O4-CdTe/CdS-Mb/GCE修饰电极。在pH7.0的0.1mol/L磷酸盐缓冲溶液(PBS)中,固定在膜内的Mb表现出良好的直接电化学性质,在-0.351V处有1对近乎可逆的氧化还原峰,为Mb中血红素辅基Fe(Ⅲ)/Fe(Ⅱ)电对的特征氧化还原峰,并显示了很好的稳定性。表明Nafion/Fe3O4-CdTe/CdS复合膜的微环境有利于Mb中Fe(Ⅲ)/Fe(Ⅱ)与电极之间的直接电子传递和Mb的固定。同时,探讨了该修饰电极表面固定的Mb对H2O2的催化还原,结果显示,该修饰电极可作为H2O2生物传感器,实现对H2O2的快速(响应时间小于5s)、准确检测,灵敏度可达30.6mA?L/mol,检出限(S/N=3)为0.89μmol/L。 相似文献
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基于二氧化钛/碳纳米管/壳聚糖纳米复合薄膜制备葡萄糖生物传感器 总被引:5,自引:0,他引:5
利用壳聚糖(CHI)溶液分散了纳米二氧化钛(nano-TiO2)和多壁碳纳米管(MWCNT),将该分散液修饰于玻碳电极表面形成纳米复合薄膜;用戊二醛为交联剂在该纳米复合层上固定了葡萄糖氧化酶(GOx),同时以二茂铁为电子媒介体构建了一种新型葡萄糖传感器。利用扫描电镜(SEM)、交流阻抗(AC)对所制备的传感器进行了表征,同时用循环伏安法(CV)和计时电流法(CA)考察了其对葡萄糖的电催化氧化性能。实验结果表明,在优化测试条件下该传感器对葡萄糖在0.5~20.0 mmol.L-1范围内有线性响应,检出限为0.2 mmol.L-1;电流达到95%的稳态时间小于5 s;此生物传感器具有良好的重现性和选择性,能有效排除抗坏血酸、尿酸等常见干扰物的影响并成功应用于饮料中葡萄糖含量的测定。 相似文献
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构造了一种以碳纳米管接枝的壳聚糖为基底,然后将羧基二茂铁电聚合在其氨基化的表面,利用负电荷的表面组装PDDA保护的纳米金,最后通过静电吸附葡萄糖氧化酶,制得了新型的葡萄糖生物传感器。在优化的实验条件下,该传感器的响应电流与其浓度在3.0×10-6~2.9×10-3mol/L范围内呈现良好的线性关系,检测限为1.4×10-6mol/L。此外,该传感器还具有灵敏度高、稳定性好和抗干扰能力强等特点。 相似文献
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通过电化学沉积将壳聚糖、葡萄糖氧化酶和碳纳米管固定到镀铂金电极上,制备了一种新型葡萄糖生物传感器.探讨了铂的电沉积时间、壳聚糖化学沉积时间、缓冲溶液pH和工作电位等对该牛物传感器的影响.实验结果表明,该生物传感器线性范围为1×10~(-6)1.2×10~(-2)mol/L,相关系数为0.9974,检测限为5.0×10~(-7)mol/L,响应时间≤8 s;血清中的尿酸、抗坏血酸等对葡萄糖的测定无干扰.利用该生物传感器测定了人血清中的葡萄糖,回收率在97%~105%之间.该生物传感器线性范围较宽,灵敏度高,响应迅速,抗干扰能力强,有望成为一种可推广的新型葡萄糖检测器. 相似文献
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基于金纳米棒-壳聚糖复合膜的葡萄糖生物传感器 总被引:3,自引:0,他引:3
本文采用金纳米棒-壳聚糖复合膜固定葡萄糖氧化酶构建电流型葡萄糖生物传感器.通过电化学交流阻抗法和循环伏安法对酶膜状态进行了表征,得到了相应的等效电路和动力学参数.实验结果表明,金纳米棒-壳聚糖复合膜可以辅助电子传递,提高电极的电流响应,并使生物传感器的使用温度范围有很大的扩展.此传感器表现出对葡萄糖溶液浓度的优良响应,线性范围在2.78×10-5mol/L—2.22×10-3mol/L,响应灵敏度约为7.819μA·cm-2(mmol/L)-1,表观米氏常数为10mmol/L.本工作还研究了温度和溶液pH值对电极电流响应的影响. 相似文献
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《Analytical letters》2012,45(5):913-926
Abstract A new nanocomposite was developed by combination of prussian blue (PB) nanoparticles and multiwalled carbon nanotubes (MWNTs) in the matrix of biopolymer chitosan (CHIT). The PB and MWNTs had a synergistic electrocatalytic effect toward the reduction of hydrogen peroxide. The CHIT/MWNTs/PB nanocomposite‐modified glassy carbon (GC) electrode could amplify the reduction current of hydrogen peroxide by ~35 times compared with that of CHIT/MWNTs/GC electrode and reduce the response time from ~60 s for CHIT/PB/GC to 3 s. Besides, the CHIT/MWNTs/PB nanocomposite‐modified GC electrode could reduce hydrogen peroxide at a much lower applied potential and inhibit the responses of interferents such as ascorbic acid (AA) uric acid (UA) and acetaminophen (AC). With glucose oxidase (GOx) as an enzyme model, a new glucose biosensor was fabricated. The biosensor exhibited excellent sensitivity (the detection limit is down to 2.5 µM), fast response time (less than 5 s), wide linear range (from 4 µM to 2 mM), and good selection. 相似文献
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Xueling Li Chi-chun Fong Minghui Huang Huimin Cao Jianlong Zhao Mengsu Yang 《Mikrochimica acta》2008,160(1-2):253-260
A high-performance amperometric glucose biosensor was developed, based on immobilization of glucose oxidase (GOx) on a copper
(Cu) nanoparticles/chitosan (CHIT)/carbon nanotube (CNT)-modified glassy carbon (GC) electrode. The Cu and CNT had a synergistic
electrocatalytic effect toward the reduction of hydrogen peroxide in the matrix of biopolymer CHIT. The Cu/CHIT/CNT modified
GC electrode could amplify the reduction current of hydrogen peroxide greatly. Besides, the Cu/CHIT/CNT modified GC electrode
reduces hydrogen peroxide at a much lower applied potential and inhibit the responses of interferents. With GOx as an enzyme
model, a new glucose biosensor was fabricated. The sensitivity of the sensor is due not only to the large microscopic area
but also to the high efficiency of transformation of H2O2 generated by enzymatic reaction to current signal. The biosensor exhibited excellent sensitivity (the detection limit is
down to 0.02 mM), fast response time (less than 4 sec), wide linear range (from 0.05 to 12 mM), and perfect selectivity.
Correspondence: Wanzhi Wei, State key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering,
Hunan University, Changsha 410082, China 相似文献
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《Electroanalysis》2017,29(3):765-772
Stable magnetic nanocomposite of gold nanoparticles (Au‐NPs) decorating Fe3O4 core was successfully synthesized by the linker of Boc‐L‐cysteine. Transmission electron microscope (TEM), energy dispersive X‐ray spectroscopy (EDX) and cyclic voltammograms (CV) were performed to characterize the as‐prepared Fe3O4@Au‐Nps. The results indicated that Au‐Nps dispersed homogeneously around Fe3O4 with the ratio of Au to Fe3O4 nanoparticles as 5–10/1 and the apparent electrochemical area as 0.121 cm2. After self‐assembly of hemoglobin (Hb) on Fe3O4@Au‐Nps by electrostatic interaction, a hydrogen peroxide biosensor was developed. The Fe3O4@Au‐Nps/Hb modified GCE exhibited fast direct electron transfer between heme center and electrode surface with the heterogeneous electron transfer rate constant (Ks ) of 3.35 s−1. Importantly, it showed excellent electrocatalytic activity towards hydrogen peroxide reduction with low detection limit of 0.133 μM (S /D =3) and high sensitivity of 0.163 μA μM−1, respectively. At the concentration evaluated, the interfering species of glucose, dopamine, uric acid and ascorbic acid did not affect the determination of hydrogen peroxide. These results demonstrated that the introduction of Au‐Nps on Fe3O4 not only stabilized the immobilized enzyme but also provided large surface area, fast electron transfer and excellent biocompatibility. This facile nanoassembly protocol can be extended to immobilize various enzymes, proteins and biomolecules to develop robust biosensors. 相似文献
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Pablo A. Gallay María D. Rubianes Fabiana A. Gutierrez Gustavo A. Rivas 《Electroanalysis》2019,31(10):1888-1894
We report an innovative supramolecular architecture for bienzymatic glucose biosensing based on the non‐covalently functionalization of multi‐walled carbon nanotubes (MWCNTs) with two proteins, glucose oxidase (GOx) (to recognize glucose) and avidin (to allow the specific anchoring of biotinylated horseradish peroxidase (b‐HRP)). The optimum functionalization was obtained by sonicating for 10 min 0.50 mg mL?1 MWCNTs in a solution of 2.00 mg mL?1 GOx+1.00 mg mL?1avidin prepared in 50 : 50 v/v ethanol/water. The sensitivity to glucose for glassy carbon electrodes (GCE) modified with MWCNTs‐GOx‐avidin dispersion and b‐HRP (GCE/MWCNTs‐GOx‐avidin/b‐HRP), obtained from amperometric experiments performed at ?0.100 V in the presence of 5.0×10?4 M hydroquinone, was (4.8±0.3) μA mM?1 (r2=0.9986) and the detection limit was 1.2 μM. The reproducibility for 5 electrodes using the same MWCNTs/GOx‐avidin dispersion was 4.0 %, while the reproducibility for 3 different dispersions and 9 electrodes was 6.0 %. The GCE/MWCNT‐GOx‐avidin/b‐HRP was successfully used for the quantification of glucose in a pharmaceutical product and milk. 相似文献
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An amperometric tyramine biosensor based on poly‐L‐lysine (PLL) and Fe3O4 nanoparticles (Fe3O4NP) modified screen printed carbon electrode (SPCE) was developed. PLL was formed on the SPCE by the electropolymerization of L‐lysine. Subsequently, Fe3O4NP suspension prepared in chitosan (CH) solution was casted onto the PLL/SPCE. Tyrosinase (Ty) enzyme was immobilized onto the modified Fe3O4?CH/PLL/SPCE and the electrode was coated with Nafion to fabricate the Ty/Fe3O4?CH/PLL/SPCE. Different techniques including scanning electron microscopy, chronoamperometry (i–t curve), cyclic voltammetry and electrochemical impedance spectroscopy were utilized to study the fabrication processes, electrochemical characteristics and performance parameters of the biosensor. The analytical performance of the tyramine biosensor was evaluated with respect to linear range, sensitivity, limit of detection, repeatability and reproducibility. The response of the biosensor to tyramine was linear between 4.9×10?7–6.3×10?5 M with a detection limit of 7.5×10?8 M and sensitivity of 71.36 μA mM?1 (595 μA mM?1 cm?2). The application of the developed biosensor for the determination of tyramine was successfully tested in cheese sample and mean analytical recovery of added tyramine in cheese extract was calculated as 101.2±2.1 %. The presented tyramine biosensor is a promising approach for tyramine analysis in real samples due to its high sensitivity, rapid response and easy fabrication. 相似文献
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基于多壁碳纳米管和氧化锌纳米棒复合物的葡萄糖生物传感器(英文) 总被引:1,自引:0,他引:1
利用多壁碳纳米管(MWCNTs)和氧化锌(ZnO)纳米棒复合物膜构建了一种新的电流型葡萄糖生物传感器。MWCNTs-ZnO复合物在超声协助下通过静电配位的方式产生。其中,ZnO纳米棒的存在加强了该复合物催化氧化H2O2的能力,增加了响应电流。与单一的MWCNTs和ZnO相比,这种纳米复合物显示了更为有效地电催化活性。在此基础上,我们以MWCNTs-ZnO复合物膜为基底,用戊二醛交联法固定葡萄糖氧化酶,电聚合邻苯二胺(PoPD)膜为抗干扰层,构建了抗干扰能力强,稳定性好,灵敏度高,响应快的葡萄糖传感器。在+0.8V的检测电位下,该传感器对葡萄糖响应的线性范围为5.0×10-6~5.0×10-3mol·L-1(R=0.997),检测限为3.5×10-6mol·L-1(S/N=3),响应时间小于10s的葡萄糖生物传感器,常见干扰物质如抗坏血酸和尿酸不影响测定。 相似文献
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基于多壁碳纳米管和聚丙烯胺层层自组装的葡萄糖生物传感器 总被引:1,自引:0,他引:1
经混酸处理后的多壁碳纳米管(MWCNTs)末端及侧壁带有含氧基团,能与阳离子聚电解质通过静电作用结合,也能与酶蛋白非特异性结合。利用层层自组装法在铂(Pt)电极表面构建了聚丙烯胺(PAA)-MWC-NTs-葡萄糖氧化酶(GOx)膜,研究了自组装薄膜的表面微观形貌和电化学性质。组装层数为6层时最优,对葡萄糖响应线性范围为5.0×10-4~2.10×10-2mol/L;检出限为1.0×10-4mol/L(S/N=3);灵敏度为4.95μA/(mmolcm2),响应时间3.80s;GOx表观米氏常数为17.79mmol。对抗坏血酸等具有较强的抗干扰能力,10天后电极响应电流保持最初的91.79%。3次平行实验的RSD为4.85%。 相似文献
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本文选用生物相容性好的壳聚糖作为基体材料,使其与戊二醛交联成网状结构包埋葡萄糖氧化酶制成电化学传感器。这种壳聚糖膜不仅可以减小葡萄糖氧化酶的流失,而且能为酶提供了适宜的微环境。用红外光谱、紫外光谱及透射电镜对膜的形态和性质进行了表征。实验结果表明该传感器具有很快的响应速度,很好的稳定性和重现性,能选择性地催化葡萄糖并测定其浓度。该传感器的制备方法简单,成本低,于冰箱中放置两周信号保持在90%以上,对葡萄糖测量的线性范围为1×10-5 - 3.4×10-3mol•L-1,当信噪比为3:1时检测限为5×10-6mol•L-1。 相似文献
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Magnetic carbon nanotube‐supported imidazolium ionic liquid (CNT‐Fe3O4‐IL) was synthesized and investigated using various characterization techniques, including Fourier transform infrared and Raman spectroscopies, X‐ray diffraction, vibrating sample magnetometry, scanning and transmission electron microscopies, and thermogravimetric and differential thermal analyses. In order to synthesize the CNT‐Fe3O4‐IL nanocomposites, Fe3O4‐decorated multi‐walled CNTs were modified with 1‐methyl‐3‐(3‐trimethoxysilylpropyl)‐1H‐imidazol‐3‐ium chloride. This catalytic system was found to be a highly stable, active, reusable and solid‐phase catalyst for the synthesis of 2‐aminothiazoles via the one‐pot reaction of ketone, thiourea and N‐bromosuccinimide under mild conditions. Immobilized magnetic ionic liquid catalysis combines the advantages of ionic liquid media with magnetic solid support nanomaterials which enables the application of nanotechnology and green chemistry in chemical processes. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献

