纳米聚苯胺修饰石墨电极的葡萄糖双酶传感器

用循环伏安法在石墨电极上制得纳米纤维聚苯胺, 并在其上固定葡萄糖氧化酶(GOD)和辣根过氧化物酶(HRP)制备葡萄糖双酶传感器. 用交流阻抗、SEM等技术对其进行表征; 考察了各种因素对双酶电极响应电流的影响以及双酶电极的稳定性. 该传感器对葡萄糖响应电流的测定在0.05 V(vs SCE)下进行, 有效避免了电活性物质的影响, 线性响应范围为0.05-2.0 mmol·L-1.     

基于ZnO纳米线的螺旋线形跨尺度葡萄糖传感器

制备了一种基于螺旋线形跨尺度结构的酶传感器, 并对该传感器进行了表征和性能测试. 将ϕ 30 μm键合Au丝以螺旋线方式手工缠绕在ϕ 125 μm光纤纤芯上, 在该Au螺旋线上用水浴法合成ZnO纳米线, 得到螺旋线形跨尺度结构; 在ZnO纳米线上物理吸附葡萄糖氧化酶(GOD), 制备了葡萄糖传感器工作电极. 利用扫描电子显微镜(SEM)图像和MatLab图像处理算子分别对螺旋线形跨尺度结构表面形貌及其上活力为50 units/mg的GOD吸附效果进行了定性和定量表征, 分析了非高斯粗糙表面与GOD吸附效果的影响关系. 基于三电极体系采用循环伏安法和计时安培法测试了制备的12个工作电极的性能, 测得该类传感器的灵敏度为(1.410±0.665) μA·L/(mmol·cm²), 线性范围为0~(4.292±0.652) mmol/L, Michaelis-Menten常数为(3.571±1.280) mmol/L, 检出限为(14.085±8.393) μmol/L. 使用活力更高的GOD可以得到性能更好的螺旋线形跨尺度葡萄糖传感器. 该类传感器可广泛应用于医药、 生物、 食品加工及环境监测领域中尿酸、 尿素、 胆固醇、 过氧化氢和苯酚等的检测.     

基于纳米铁氰化镍修饰二氧化钛纳米管阵列电极的非酶葡萄糖传感器

以二氧化钛纳米管阵列(TNTs)为基底,利用脉冲电沉积的方法将Ni纳米粒子沉积在TNTs管内,通过循环伏安法将Ni转化为铁氰化镍(NiHCF),构造了新型的非酶型葡萄糖生物传感器(NiHCF/TNTs修饰电极)。在优化的实验条件下,传感电极的灵敏度为663μA/(mmol cm2);响应电流与葡萄糖浓度在1～23mmol/L范围内呈现良好的线性关系。在低浓度检测下,线性范围为2×10-3～1.0 mmol/L;检出限为0.5μmol/L。本传感电极具有灵敏度高、稳定性好和抗干扰能力强等特点。     

Microwave-assisted One-pot Synthesis of Ag NPs/C and Its Application in H2O2 and Glucose Detection

The facile preparation of Ag NPs/C via a one-pot strategy was carried out by microwave treatment of a mixed aqueous solution of AgNO₃ and glucose at 180℃ for 20 min without the presence of extra reducing agent. The as-synthesized Ag NPs/C showed high catalytic performance toward the reduction of H₂O₂. The H₂O₂ sensor constructed with as-synthesized Ag NPs/C exhibited a short amperometric response time of less than 2 s. The linear range was approximately (0.1-50) mmol/L(r=0.997), and the detection limit was approximately 3.3 μmol/L at a signal-to-noise ratio of 3. A glucose biosensor was fabricated by immobilizing glucose oxidase onto Ag NPs/C- modified glassy carbon electrode to detect glucose. The glucose sensor had a wide linear response range of 2-22 mmol/L(r=0.999) and a detection limit of 190 μmol/L.     

A ultrasensitive nonenzymatic glucose sensor based on Cu2O polyhedrons modified Cu electrode

A novel nonenzymatic glucose sensor was successfully fabricated based on the Cu2O polyhedrons covered Cu foil.The Cu2O polyhedrons covered Cu foil was constructed via a facile,low-cost and larger scale producible method.The Cu2O polyhedrons covered Cu foil can be directly used as the working electrode of nonenzymatic glucose sensor,which present good stability and flexibility.The results indicated that the Cu2O polyhedrons modified Cu electrode(Cu2O/Cu electrode) showed high electrocatalytic activity for the oxidation of glucose in alkaline solution.There are two linear regions of glucose concentration for the glucose sensor based on Cu2O/Cu electrode,respectively in 10 mmol/L to 0.53 mmol/L(sensitivity:3029.33 mA(mmol/L) à1 cm à2) and in 0.53-7.53 mmol/L(sensitivity:728.67 mA(mmol/L) à1 cm à2).     

脉冲恒电位一步法制备聚3,4-乙烯二氧噻吩石墨烯复合材料构建无酶葡萄糖传感器

本研究利用石墨烯(rGO)与3,4-乙烯二氧噻吩(EDOT)单体芳香环之间的π-π*相互作用和氢键作用,采用脉冲恒电位一步法制备了聚3,4-乙烯二氧噻吩石墨烯(PEDOT-rGO)复合膜,将纳米镍(NiNPs)电沉积在此复合膜(PEDOT-rGO)表面,制备了NiNPs/PEDOT-rGO修饰玻碳电极(NiNPs/PEDOT-rGO/GCE),研究了此修饰电极对葡萄糖的电催化氧化性能.实验结果表明,此NiNPs/PEDOT-rGO/GCE可以作为无酶传感器实现对葡萄糖的检测.本方法稳定性高,选择性好,线性范围宽(2μmol/L~58 mmol/L),检出限低至0.7μmol/L,可以用于对葡萄糖的快速、灵敏检测.     

Glucose sensor using a phospholipid polymer-based enzyme immobilization method

An electroenzymatic glucose sensor based on a simple enzyme immobilization technique was constructed and tested. The glucose sensor measures glucose concentrations as changes of oxygen concentrations induced by enzymatic reactions. The immobilizing procedure was developed with the purpose of producing wearable biosensors for clinical use. Two types of biocompatible polymers, 2-methacryloyloxyethyl phosphorylcholine (MPC) copolymerized with dodecyl methacrylate (PMD) and MPC copolymerized with 2-ethylhexyl methacrylate, were compared as a sensitive membrane of biosensors. The PMD enzyme membrane had a better response time. Linearity, reproducibility, effect of the concentrations of immobilized enzyme and drifts of sensor characteristics in long-term tests were also investigated. The linear characteristics were confirmed with glucose concentration from 0.01 to 2.00 mmol/l, with a coefficient of determination of 0.9999. The average output current for 1 mmol/l and the standard deviation were 0.992 and 0.0283 muA. Significant changes in the sensor's characteristics were not observed for 2 weeks when it was kept in a refrigerator at 4 degrees C. Because of the simple procedure, the enzyme immobilization method is not only useful for wearable devices but also other devices such as micro total analysis systems.     

Glucose Microbiosensor Based on MnO2 and Glucose Oxidase Modified Carbon Fiber Microelectrode

A glucose microbiosensor has been developed using electrochemical codeposition of glucose oxidase (GOx) along with MnO₂ as mediator, onto a single carbon fiber microelectrode. A two‐step deposition of only MnO₂ initially and then of MnO₂ in the presence of GOx has been introduced to ensure appropriate activity of the mediator. Several parameters such as deposition potential and time, concentration levels etc. have been characterized and optimized. A thin Nafion film was applied as an immobilization/encapsulation and interference‐free protective layer. The proposed microbiosensor was employed as an amperometric glucose detector at pH 7.5 at an operating potential of +0.58 V (vs. Ag/AgCl). The microbiosensor is characterized by a well‐reproducible amperometric response, linear signal‐to‐glucose concentration range from 1.5 mmol L^?1 to 15 mmol L^?1, and a limit of detection (S/N=3) of 0.8 mmol L^?1. The microbiosensor exhibits good stability over more than ten hours of continuous measurement.     

基于固定化酶的流动荧光法测定血清中的葡萄糖

本文将固定化酶柱，光纤以及停流技术结合起来，研究了以廉价而易得的硫胺素为荧光底物的葡萄糖的荧光分析，提出了一种快速、简便、精确地测定葡萄糖的新方法。其线性范围为１．０￣６０．０ｍｇ／Ｌ，线性相关系数为０．９９９，检测限为０．１５ｍｇ／Ｌ。以５．０ｍｇ／Ｌ的葡萄糖作精度试验，ＲＳＤ％＝２．１％（ｎ＝１１）。该方法已成功地用于血清中葡萄糖的测定，结果与光度法相符。     

碳纳米管负载铂-二氧化钌纳米颗粒用于葡萄糖传感器的研究

建立了多壁碳纳米管(MWNTs)负载铂二二氧化钌纳米颗粒的液相化学还原法.以Nafion为固定剂,将Pt-RuO2/MWNTs复合材料修饰于玻碳电极的表面,制备了一种无酶型葡萄糖传感器.实验表明:复合材料修饰的电极对葡萄糖响应电流明显,并且受抗坏血酸(AA)、多巴胺(DA)和尿酸(UA)的干扰小.本实验采用安培法测定葡萄糖,线性范围为2 0×10 3～1.0×10-2 mol/L(R～0.9965);灵敏度为119.26 μA cm-2(mmol/L)-1;检出限为1.25×10 -5 mol/L(信噪比为3);响应时间为4.8 s.PtRuO2/MWNTs修饰电极可作为性能良好的无酶型葡萄糖传感器.     

基于钒酸铋半导体材料的光电化学葡萄糖传感器的研究

葡萄糖浓度的检测在食品、医药、环境等领域的应用很广泛,因此,发展具有低成本、高灵敏度、高选择性的葡萄糖传感器具有重要意义.光电化学传感器具有激发源与检测信号源相互独立的特点,被认为是一种潜在的高灵敏的葡萄糖检测方法.通过电化学沉积及高温热处理两步法在氟掺杂的SnO2透明导电玻璃(FTO)基底上制备了BiVO4薄膜.通过...     

二茂铁-AQ修饰碳纤维微葡萄糖传感器的研究

本文用二茂铁、AQ成功地制备了微葡萄糖传感器。Eastman-AQ(AQ-55D,AQ29D)是一种新型的聚合物(磺酸酯)阳离于交换剂,涂于电极表面上,形成的膜除具有强的附着力外,同时还具有预富集、离子交换及防污性能。制得的电极具有制作方法简单、快速、重现性好,抗干扰能力强等特点。检测上限15.0 mmol/L,响应时间小于6s。由于AQ强的附着力,二茂铁及酶的流失较小。电极的稳定性有所提高。     

基于Dy_2(MoO_4)_3-AuNPs复合纳米材料的葡萄糖生物传感器

采用水热法合成了纳米材料钼酸镝[Dy_2(MoO_4)_3],并制备了Dy_2(MoO_4)_3-AuNPs复合材料,利用该复合材料固定葡萄糖氧化酶(GOD)构建了葡萄糖生物传感器.通过透射电子显微镜(TEM)、紫外-可见光谱(UV-Vis)和能谱分析(EDS)等手段对所制备的材料进行了表征,并利用电化学阻抗谱(EIS)和循环伏安(CV)曲线研究了该传感器的电化学性能.结果表明,Dy_2(MoO_4)_3-AuNPs复合材料具有较好的生物相容性,能增强固定化的GOD的生物活性,并促进GOD在电极表面的电子传递速率;该传感器在葡萄糖浓度为0.01~1.0 mmol/L范围内葡萄糖浓度与响应电流呈较好的线性关系,最低检出限为3.33μmol/L(S/N=3),该生物传感器还具有较好的稳定性和重现性.     

葡萄糖传感器聚氨酯扩散限制膜响应动力学的研究

对采用聚氨酯薄膜作为扩散限制膜的葡萄糖传感器的响应动力学进行了分析与计算。通过对葡萄糖氧化酶（GOD）的米氏常数Km值及衡量扩散控制作用的Y值的计算,从理论上说明了扩散限制膜的引入是提高葡萄糖传感器响应线性范围的一种有效方法。计算结果表明：GOD经壳聚糖固定化后米氏常数Km从9.6减小到7.2mmol/L;随着制膜液浓度及浸渍次数的增加,Y值增加,线性范围扩大,与实验结果是一致的。     

鱼鳔膜为基质的生物传感器测定葡萄糖的研究

以鱼鳔膜为基质同定葡萄糖氧化酶,偶联氧电极,构建了葡萄糖生物传感器,通过测定溶解氧浓度的变化定量测定葡萄糖.考察了酶浓度、pH值、缓冲液浓度对传感器的影响,优化了实验条件:即酶浓度为1 mg,pH 7.0,缓冲液浓度为100 mmol/L.此传感器具有较宽的线性范围(0.016～1.2 mmol/L),较短的响应时间(...     

Colorimetric detection of glucose using a boronic acid derivative receptor attached to unmodifed AuNPs简

A simple, cheap and non-enzymatic colorimetric strategy for glucose detection has been designed based on the interactions between a phenylboronic acid （PBA） derivative, which is coupled with gold nanoparticles （AuNPs） as the colorimetric reporters, and glucose. The PBA-AuNPs hybrid system proposed here exhibits ordered photochemistry behaviors upon the addition of glucose at different pH values. There are two linear regions of glucose concentration for the glucose sensor at different pH values, i.e., between 0.1 mmol/L and 9.8 mmol/L at pH 6 with the detection limit of 64μmol/L and between 0 and 6.5 mmol/L with the detection limit of 48 μmol/L at pH 9, respectively. To test the practicality of the sensor system, we also applied this assay to detect a glucose sample in the artificial saliva.     

High-Sensitive Glucose Biosensor Based on Ionic Liquid Doped Polyaniline/Prussian Blue Composite Film

The Prussian blue/ionic liquid-polyaniline/multiwall carbon nanotubes (PB/IL-PANI/MWNTs) composite film was fabricated by using cyclic voltammetry. The ion liquid acting as a lubricating agent, could enhance the electron delocalization degree and reduce the struc-tural defects of the polyaniline. The surface morphology of the composite film revealed that the PB nanoparticles have smaller size than that in pure PB film. Due to the introduction of ion liquid, the PB/IL-PANI/MWNTs composite film showed wonderful synergistic effect which can remarkably enhance sensitivity, expand linear range and broaden acidic adapt-ability for hydrogen peroxide detection. The composite film demonstrated good stability in neutral solution contrast to pure PB film, with a linear range from 2.5 μmol/L to 0.5 mmol/Land a high sensitivity of 736.8 μA·(mmol/L)^-1·cm^-2 for H₂O₂ detection. Based on the com-posite film, an amperometric glucose biosensor was then fabricated by immobilizing glucose oxidase. Under the optimal conditions, the biosensor also exhibits excellent response to glucose with the linear range from 12.5 μmol/L to 1.75 mmol/L and a high sensitivity of 94.79 μA (mmol/L)^-1·cm^-2 for H₂O₂. The detection limit was estimated 1.1 μmol/L. The resulting biosensor was applied to detect the blood sugar in human serum samples without any pretreatment, and the results were comparatively in agreement with the clinical assay.     

Glucose Biosensor Using Glucose Oxidase Immobilized in Polyaniline

A biosensor for glucose utilizing kinetics of glucose oxidase (EC 1.1.3.4.) was developed. The enzyme was immobilized on polyaniline by covalent bonding, using glutaraldehyde as a bifunctional agent. The system showed a linear response up to 2.2 mM of glucose with a response time of 2.5–4.0 min. In addition, the immobilized enzyme had a higher activity between pH 6.5 and 7.5. The system retained 50% of its activity after 30 d of daily use. The optical absorption spectra of the polyaniline/glucose oxidase electrode after glucose had been added to the buffer solution showed that the absorption band around 800 nm had changed considerably when glucose was allowed to react with the electrode. This optical variation makes polyaniline a very promising polymer for use as a support in optical sensor for clinical application.     

基于聚多巴胺/铜微粒自组装多层膜的无酶葡萄糖传感器

利用多巴胺易于在电极表面发生自聚反应,且聚多巴胺膜中富含邻苯二酚等反应性基团,可通过二次反应实现电极表面的进一步功能化修饰的特点,在玻碳电极(GCE)表面,将多巴胺自聚膜(PDA)与铜微粒(Cu)进行层-层自组装,构建了无酶葡萄糖电化学传感器(GCE/(PDA/ Cu) n )。传感器的灵敏度可通过控制多层膜的组装层数进行调控。采用紫外-可见光谱跟踪表征了多层膜的组装过程,结果表明,多层膜的生长是逐步且均匀的过程。采用循环伏安法和电流-时间曲线法研究了修饰电极对葡萄糖的电催化氧化性能。对于GCE/(PDA/ Cu)4,检测葡萄糖的线性范围为0.5~9.0 mmol/ L,检出限为5.8μmol/ L(S/ N=3)。本传感器具有良好的重现性、稳定性和较强的抗干扰能力。将本传感器用于血清中葡萄糖的测定,结果令人满意。     

Glucose concentration determination based on silica sol-gel encapsulated glucose oxidase optical biosensor arrays

Optical biosensor arrays for rapidly determining the glucose concentrations in a large number of beverage and blood samples were developed by immobilizing glucose oxidase (GOD) on oxygen sensor layer. Glucose oxidase was first encapsulated in silica based gels through sol-gel approach and then immobilized on 96-well microarrays integrated with oxygen sensing film at the bottom. The oxygen sensing film was made of an organically modified silica film (ORMOSIL) doped with tris(4,7-diphenyl-1,10-phenanthroline) ruthenium dichloride (Ru(dpp)₃Cl₂). The oxidation reaction of glucose by glucose oxidase could be monitored through fluorescence intensity enhancement due to the oxygen consumption in the reaction. The luminescence changing rate evaluated by the dynamic transient method (DTM) was correlated with the glucose concentration with the wide linear range from 0.1 to 5.0 mM (Y = 13.28X − 0.128, R = 0.9968) and low detection limit (0.06 mM). The effects of pH and coexisting ions were systemically studied. The results showed that the optical biosensor arrays worked under a wide range of pH value, and normal interfering species such as Na⁺, K⁺, Cl⁻, PO₄³⁻, and ascorbic acid did not cause apparent interference on the measurement. The activity of glucose oxidase was mostly retained even after 2-month storage, indicating their long-term stability.