基于表面重建螺旋型铂铱电极的葡萄糖生物传感器

通过对螺旋型铂铱电极表面进行化学腐蚀和电化学沉积铂纳米粒子实现电极表面的重建和优化,研究了螺旋型铂铱电极在不同腐蚀时间和电沉积时间下的形貌及对过氧化氢(H2O2)的催化活性.对表面重建的工作电极涂覆氧化酶和半透膜,制备出了铂纳米粒子/葡萄糖氧化酶/环氧聚氨酯酶电极,并将其用作葡萄糖传感器的工作电极.传感器计时电流检测结果表明,表面重建后的酶电极传感器对葡萄糖的检测范围扩大为2~45 mmol/L,优于裸铂铱酶电极传感器,电流响应值和灵敏度得到明显提升,同时传感器还具有良好的稳定性和选择性.     

硅溶胶-凝胶包埋纳米金和酶的葡萄糖生物传感器

采用溶胶-凝胶技术将金纳米粒子和葡萄糖氧化酶一次性固定于硅溶胶-凝胶的网络结构中,制备了葡萄糖生物电化学传感器并优化了传感器的制备条件。酶电极对葡萄糖具有良好的电化学响应,葡萄糖浓度在0.02~2.0 mmol/L范围内和催化电流呈线性关系,检出限为0.005 mmol/L。酶电极在4 ℃下贮存100 d后对葡萄糖的响应仅下降8%。该酶电极灵敏度高、响应快、稳定性好。     

基于多层叉指超微带电极阵列的葡萄糖传感器

采用多层工艺和光刻方法在玻璃衬底上加工了亚微米级金叉指型超微带电极阵列（IDA）,IDA电极的宽度为362nm,电极表面位于沟槽内。实验表明,所加工的IDA电极可作为生物和化学传感器的一次性超微基体电极。采用电聚合的方法将葡萄糖氧化酶（GOD）和吡咯（PPy）固定于IDA电极,该修饰电极可作为葡萄糖传感器。采用该葡萄糖传感器对磷酸钾缓冲溶液（pH7．0）中的葡萄糖浓度进行了比对测量,在2．0-7．0mmol／L的浓度范围内,传感器的响应时间为10s;灵敏度为14．6nA／（mmol／L）,相关系数为0．999。     

(C_6H_5)_4■·■(CH_3)_4离子缔合物在1,1′-二甲基二茂铁介体电流型葡萄糖生物传感器中的应用

本文以1.1’-二甲基二茂铁(DMFeCP_2)为电子转移介体,以含(C_6H_5)_4B·N(CH_3)_4离子缔合物的碳糊电极为基础电极,研制成了电流型葡萄糖生物传感器。该传感器在选定的电位下Vc,尿酸不干扰,线性范围为1×10~4～1.2×10~3mol/L,响应时间为50s.K_M~(app)为11.6mmol/L,有效寿命达30天。用该传感器对人血清中的葡萄糖进行测定,与传统的分光光度法测定结果比较吻合。     

基于平面薄膜型电极的介体型半乳糖传感器的制备

以微电子薄膜技术制作的平面薄膜型电极为基底电极，β-环糊精与戊二醛缩合成的β-环糊精聚合物与二茂铁甲醇形成稳定的包络物，以此包络物中的二茂铁甲醇为电子介体，制成了半乳糖传感器。传感器的最佳工作电位0．3V，适宜的pH值范围7．0-9．0。传感器对半乳糖测定的线性范围为0．5-5．0mmol/L，响应时间1min。该传感器在两个星期内连续使用，响应电流无明显变化。保存一个月后测试仍有较好的电流响应。由于低测定电位和β-环糊精聚合膜的阻挡作用，能有效减少抗坏血酸、尿酸的干扰。     

以苯硼酸为识别物质的电化学阻抗糖传感器的制备

以苯硼酸为识别物质,利用巯基自组装法将半胱胺与4-甲酰基苯硼酸反应形成的Schiff’s碱固定于金电极表面,构建了检测葡萄糖、乳糖、甘露聚糖的电化学阻抗传感器。根据传感器结合糖前后电子转移阻抗值的变化(ΔR et),分别进行了葡萄糖、乳糖、甘露聚糖的分析测定。以pH 9.0的5 mmol/L K3[Fe(CN)6]-5 mmol/L K4[Fe(CN)6]平衡电对溶液作为检测溶液,ΔR et与葡萄糖的浓度在5.05×10#9~5.05×10#5mol/L之间呈良好的线性关系,检出限为9.7×10#10mol/L(S/N=3);ΔR et与乳糖的浓度在2.78×10#9~2.78×10#5mol/L之间呈良好的线性关系,检出限为8.1×10#10mol/L(S/N=3);ΔR et与甘露聚糖的浓度在4.35×10#9~4.35×10#5mol/L之间呈良好的线性关系,检出限为3.4×10#10mol/L(S/N=3)。该方法简单、灵敏、成本低,可用于不同种类糖的分析检测。     

基于谷胱甘肽-壳聚糖自组装的葡萄糖生物传感器

采用壳聚糖-谷胱甘肽复合膜固定葡萄糖氧化酶构建电流型葡萄糖生物传感器。通过循环伏安法对酶膜状态进行表征,实验结果表明,壳聚糖-谷胱甘肽复合膜可以辅助电子传递,提高电极的电流响应。选用正交表L9(34)设计实验方案,分析最佳实验条件。在优化条件下,该传感器对葡萄糖溶液浓度有良好的线性关系,线性范围为1～18 mmol/L,检出限为1.3 mmol/L。实验表明,此传感器具有响应快、稳定性及选择性良好的特点。适用于临床尿样中葡萄糖的测定。     

新型海胆状钨铜自支撑电极的制备及其葡萄糖无酶传感

该文采用方波脉冲法在光滑W70Cu30电极表面快速、高效制备海胆状结构的自支撑电极（U－WCu）,并用于葡萄糖的电化学检测,其表现出比单一纳米铜（N－Cu）更优异的电化学性能。考察了脉冲时间、脉冲频率和电势范围对葡萄糖电催化氧化的影响。采用循环伏安法（CV）比较了U－WCu电极和N－Cu电极在0.1 mol/L NaOH溶液中对葡萄糖的电催化氧化行为,构建了基于U－WCu海胆状电极的无酶电化学传感器。该电极的线性范围宽（2 μmol/L ~ 10 mmol/L）,检出限（S/N = 3）低至0.21 μmol/L,灵敏度高达4 983 μA?mmol?L-1?cm-2。方法有极好的重复性、重现性,良好的抗干扰性,以及长达8周的稳定性,并成功用于葡萄糖注射液中葡萄糖含量的测定。     

高性能多级花状Co3O4基无酶葡萄糖电化学传感器

以硝酸钴、碳酸钠、尿素为原料,泡沫镍为基体,采用水热和煅烧相结合的二步法制备了一种多级花状Co_3O_4/Ni异质结构的无酶葡萄糖传感器。通过X射线衍射与扫描电镜对Co_3O_4/Ni电极的成分及形貌进行了表征,并采用循环伏安法在1mol/L KOH溶液中测试了Co_3O_4/Ni异质结构葡萄糖传感器电极的电化学性能。结果表明,通过二步法在泡沫镍表面制备的Co_3O_4呈现多级花状纳米纤维结构。将制备的Co_3O_4/Ni异质结构作为电极构建的无酶葡萄糖传感器表现出响应时间快(低于5s)、检测灵敏度高(7.4m A·(mmol/L)~(-1)·cm~(-2))、检出限低(1.17μmol/L,S/N=3)和线性检测范围宽(0~5 mmol/L)的特点。进一步的抗干扰性检测表明所制备的传感器在+0.44V vs.SCE对葡萄糖表现出良好的选择性。本文所制备的多级花状Co_3O_4基电极在无酶葡萄糖传感器的发展中有着很大的应用潜力。     

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X射线衍射分析(XRD)、拉曼光谱(Raman)、扫描电子显微镜分析(SEM)等表征技术对BiVO₄电极的结构组成和微观形貌等性质进行了表征. 结果表明, 所制得的BiVO₄为单斜晶系, 形貌为黏连的纳米颗粒. 进一步地, 对基于BiVO₄半导体构建的光电化学葡萄糖传感器性能进行了评价. 电化学测试表明, 葡萄糖在BiVO₄电极上的氧化电流与葡萄糖的浓度能够呈现出很好的线性关系, 在5~35 mmol/L浓度区间的检测灵敏度为17.38 μA/cm2/(mmol/L). 研究为葡萄糖提供了一种简易廉价的检测新策略.     

Multianalyte Biosensors for the Simultaneous Determination of Glucose and Galactose Based on Thin Film Electrodes

A multianalyte biosensor for the simultaneous determination of glucose and galactose was developed by immobilizing glucose oxidase (GOD) and galactose oxidase (GAO) on Nation-modified thin film platinum disk electrodes. The dual Pt working electrodes with disk shape and the surrounding ring shaped counter electrode were fabricated by thin film technology,which were integrated onto the same microchip. The response of the designed biosensor for glucose and galactose were linear up to 6.0mmol/L and 3.5mmol/L with sensitivities of 0.3μA/mmol/L and 0.12μA/mmol/L, respectively. No cross-talking effect was observed.     

Enzymatic/Immunoassay Dual‐Biomarker Sensing Chip: Towards Decentralized Insulin/Glucose Detection

Performing bioassay formats based on enzyme and antibody recognition reactions with a single detection chip remains an unmet challenge owing to the different requirements of such bioassays. Herein, we describe a dual‐marker biosensor chip, integrating enzyme and antibody‐based assays for simultaneous electrochemical measurements of insulin (I) and glucose (G). Simultaneous G/I sensing has been realized by addressing key fabrication and operational challenges associated with the different assay requirements and surface chemistry. The I immunosensor relies on a peroxidase‐labeled sandwich immunoassay, while G is monitored through reaction with glucose oxidase. The dual diabetes biomarker chip offers selective and reproducible detection of picomolar I and millimolar G concentrations in a single microliter sample droplet within less than 30 min, including direct measurements in whole blood and saliva samples. The resulting integrated enzymatic‐immunoassay biosensor chip opens a new realm in point‐of‐care multiplexed biomarker detection.     

Thin-film biosensor for the measurement of glucose concentration in human serum and urine

Solid-state technology and pulse electroplating were used to fabricate a glucose biosensor based on hydrogen peroxide detection. This glucose biosensor was composed of thin-film electrodes, and enzyme-immobilized and deactivated enzyme-immobilized membranes. The electrodes were fabricated by metallic film deposition. Cr and Ni adhesive layers were applied successively by vapour deposition on the thermally oxidized SiO₂ isolating layer on a silicon substrate, and then the two metallic layers were patterned by the photolithographic method. Subsequently, a 1 μm thick Au layer was applied by means of pulse electroplating, forming two anodes and one common cathode in each sensor chip. On one anode, glucose oxidase (GOD) was immobilized by cross-linking with bovin serum albumin and glutaraldehyde. A deactivated GOD-immobilized membrane was formed on the other anode, which worked as a reference working electrode. A novel differential measurement system was used to treat the output signals of the two anodes by adjusting the initial position of the response curves, compensating amplifications of the individual I—V converters and treating the output signals with a subtraction circuit in order to decrease measurement error. The test results showed that the signal of ascorbic acid up to 4.5 mmol 1⁻¹ or uric acid up to 1.2 mmol 1⁻¹ was successfully cancelled. Glucose concentrations in the range 0.02–4.0 mmol/1 could be detected and an excellent linear response was obtained in the low concentration range. The correlation coefficient between the result of the enzyme electrode and the clinically enzymatic method for glucose measurement in human serum was 0.9912. Correlated results between the biosensor method and the routine clinical method for the measurement of glucose concentration in urine were obtained. The lifetime of the enzyme electrode was over 2 months.     

基于普鲁士蓝电催化的三维多孔壳聚糖膜葡萄糖生物传感器的研制

利用电沉积方法对普鲁士蓝和壳聚糖/SiO2纳米粒子复合膜进行组装,用刻蚀法除去SiO2粒子,制备出孔径大小均匀的多孔壳聚糖/普鲁士蓝膜,这种三维多孔膜具有良好的微生物环境、比表面积大、孔隙率高,有利于负载更多的葡萄糖氧化酶,从而构建了一种灵敏度高、稳定性好、响应时间短、检测范围宽的葡萄糖生物传感器。     

Incubation type Si-based planar ion channel biosensor

A new planar-type ion channel biosensor with the function of cell culture has been fabricated using silicon on an insulator substrate as the sensor chip material. Coating of the sensor chip with fibronectin was essentially important for cell incubation on the chip. Although the seal resistance was quite low (∼7 MΩ) compared with the pipette patch-clamp gigaohm seal, the whole-cell channel current of the transient receptor potential vanilloid type 1 (TRPV1) channel expressing HEK293 cells was successfully observed, with a good signal-to-noise ratio, using capsaicin as a ligand molecule. Figure A new planer type ion channel biosensor with function of cell culture is fabricated using the silicon on insulator substrate as the sensor chip material. The coating of the sensor chip by the fibronectin was essentially important for the cell incubation on the chip. Whole cell channel current of TRPV1 channel was successfully observed using capsaicin as a ligand molecule with good signal to noise.     

Plasma-Polymerized Thin Films for Enzyme Immobilization in Biosensors

Abstract

Polymer films deposited on thin film noble metal electrodes on silicon chips, utilizing plasma polymerization are shown to be suited for immobilization of enzymes. Glucose oxidase is covalently coupled via amino- or carboxyl-groups of polymer films made by plasma polymerization of 2-amino-benzotrifluoride, acrylic or methacrylic acid. The concentration of these active surface groups increases by after-treatment in an ammonia- or oxygen-plasma. A biosensor consisting of a thin film metal electrode, plasma polymer film and immobilized glucose oxidase shows an amperometric response to glucose with a fast response time.     

流动注入式乳酸生物传感器

研制了一种测定L－乳酸的生物传感器,将乳酸氧化酶（LOD）通过共价键固定在尼龙钢上制备乳酸氧化酶膜,将制得的酶膜固定在氧电极上构成乳酸生物传感器;将透析膜放在氧化酶膜上产生对L－乳酸扩散高度限制来改变该生物传感器的响应;酶膜机械强度高,在氧电极上反复装卸而不损坏,所构成的乳酸生物传感器的校正曲线的乳酸定量上限达5mmol/L,响应时间小于30s;初步血样测试的结果显示该乳酸生物传感器用于临床血乳酸的测定具有可行性。     

Sol-gel-derived prussian blue-silicate amperometric glucose biosensor

A new type of inorganic biosensor is introduced. The sensor comprises glucose oxidase enzymes encapsulated in a sol-gel-derived Prussian blue-silicate hybrid network. Glucose is detected by the biocatalytic reduction of oxygen followed by catalytic reduction of hydrogen peroxide by the Prusian blue catalyst. The sol-gel silicate entails a rigid encapsulating matrix, the Prussian blue provides chemical catalysis and charge mediation from the reduction site to the supporting electrode, and the enzyme is responsible for the biocatalysis. The feasibility of a dual optical/electrochemical mode of analysis is also demonstrated.     

Integrated Microcentrifuge Carbon Entrapped Glucose Oxidase Poly (N-Isopropylacrylamide) (pNIPAm) Microgels for Glucose Amperometric Detection

This study demonstrates a miniaturized integrated glucose biosensor based on a carbon microbeads entrapped by glucose oxidase (GOx) immobilized on poly (N-isopropylacrylamide) (pNIPAm) microgels. Determined by the Lowry protein assay, the pNIPAm microgel possesses a high enzyme loading capacity of 31?mg/g. The pNIPAm GOx loaded on the microgel was found to maintain a high activity of approximately 0.140?U determined using the 4-aminoantipyrine colorimetric method. The integrated microelectrochemical cell was constructed using a microcentrifuge vial housing packed with (1:1, w/w) carbon entrapped by pNIPAm GOx microgels, which played the dual role of the microbioreactor and the working electrode. The microcentrifuge vial cover was used as a miniaturized reference electrode and an auxiliary electrode holder. The device can work as biosensor, effectively converting glucose to H₂O₂, with subsequent amperometric detection at an applied potential of ?0.4?V. The microelectrochemical biosensor was used to detect glucose in wide linear range from 30?µM to 8.0?mM, a low detection limit of 10?µM, a good linear regression coefficient (R²) of 0.994, and a calibration sensitivity of 0.0388?µA/mM. The surface coverage of active GOx, electron transfer rate constant (ks), and Michaelis–Menten constant (K_M^app) of the immobilized GOx were 4.0?×?10^?11?mol/cm², 5.4?s^?1, and 0.086?mM, respectively. To demonstrate the applicability and robustness of the biosensor for analysis of high sample matrix environment, glucose was analyzed in root beer. The microelectrochemical device was demonstrated for analysis of small sample (<50?µL), while affording high precision and fast signal measurement (≤5?s).     

基于蛋白质直接电子转移的全胆固醇传感器

以壳聚糖为载体, 将血红蛋白、胆固醇氧化酶及胆固醇酯酶固定在玻碳电极表面, 在不使用任何电子媒介体的条件下, 利用血红蛋白和电极之间的直接电子转移, 制备出高选择性的全胆固醇生物传感器, 并用于测定血清中总胆固醇含量. 利用循环伏安法和恒电位法研究了该传感器的电化学特性. 在优化的实验条件下, 该传感器对胆固醇响应的线性范围为10~110 mg/dL, 检出限为5 mg/dL(信噪比的3倍), 响应时间为60 s. 对人血清中总胆固醇的测定表明, RSD小于6.2%, 回收率为95%~106%.