铂纳米颗粒修饰直立碳纳米管电极的葡萄糖生物传感器

基于Pt纳米颗粒修饰直立的碳纳米管电极制备了葡萄糖生物传感器.铂纳米颗粒是利用电位脉冲沉积法修饰到直立碳纳米管上的,可以增强电极对酶反应过程当中产生的过氧化氢的催化行为.用扫描电镜和透射电镜观察了直立碳纳米管在修饰Pt纳米颗粒前后的形态.该酶电极对葡萄糖的氧化表现出很好的响应,线性范围为1×10-5～7×10-3mol/L,响应时间小于5s,并且有很好的重现性.     

基于碳纳米管体修饰的溶胶-凝胶葡萄糖生物传感器

采用多壁碳纳米管(MWNTs)体修饰石墨作为裸电极,结合正硅酸乙酯与聚乙二醇溶胶凝胶法包埋葡萄糖氧化酶制成直接电子传递型葡萄糖生物传感器。实验结果表明,当V(水):V(正硅酸乙酯):V(聚乙二醇)=1:3:6,V(凝胶):V(酶溶液)=2:1,在1mL聚乙二醇中加入6mg的MWNTs,溶胶老化时间为60h时,所制得的传感器在葡萄糖浓度为5.0×10-4～5.0×10-2mol/L范围内呈线性关系j(μA/cm-2)=0.9454c(mmol/L)+43.986,线性相关系数为0.9849,检出限为1×10-6mol/L。     

基于掺杂碳纳米管的复合体系电化学生物传感器研究

制备了含有铂纳米颗粒(NSPt)的壳聚糖(CHIT)和正硅酸四乙酯(TEOS)溶胶-凝胶溶液,将多壁碳纳米管(MWCNTs)分散于制备的CHIT和TEOS溶胶-凝胶混合物体系,并用高倍透射电镜(TEM)和扫描电子显微镜(SEM)对NSPt-CHIT表面和MWCNTs进行了表征。此种复合膜修饰玻碳电极对过氧化氢有灵敏的电化学响应。通过在此复合膜修饰的玻碳电极上固定葡萄糖氧化酶(GOx)制备了葡萄糖生物传感器。该传感器对葡萄糖在0.05~8 mmol/L范围有线性响应,相关系数为0.996,检出限(S/N=3)为10μmol/L。传感器对葡萄糖有灵敏响应,并有很好的重现性和稳定性,应用于实际样品体系的回收试验,结果良好。     

离子结合物在二茂铁介体电流型葡萄糖生物传感器中的应用研究

二茂铁及其衍生物由于氧化还原可逆性好,不溶于水,因此可利用其作介体电流型生物传感器的电子转移介体。但该类传感器的重现性、稳定性差。本文首次提出以含(C_6H_5)_4·(CH_3)_4离子缔合物的碳糊电极为基础电极,以二茂铁(FeCp_2)为电子转移介体制成葡萄糖生物传感器。该传感器重现性、稳定性好,响应迅速,测量准确度高。     

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

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%。     

用羟基磷灰石和单壁碳纳米管制备葡萄糖传感器的研究

在滴涂法制得单壁碳纳米管(SWNTs)修饰电极的基础上,采用电化学方法沉积纳米羟基磷灰石(HA)涂层,进而利用分子组装技术将葡萄糖氧化酶(GOD)固定到该电极上,制得的修饰电极的循环伏安测量结果表明,GOD发生了直接的电子传递.GOD-HA-SWNTs/GC修饰电极对不同浓度的葡萄糖呈现两个良好的线性响应范围,有望开发...     

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

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。     

血红蛋白-氮掺杂碳纳米管电化学生物传感器检测水中溴酸盐

以高导电性的氮掺杂碳纳米管为固载基底,以血红蛋白为识别元件,构建了一种新型溴酸盐(BrO₃^-)电化学生物传感器。该传感器对BrO₃^-表现出较高的灵敏度(0.02519μA/(μmol/L))、较低的检出限(75.43 nmol/L)和较宽的线性范围(1×10^-7～4.66×10-5 mol/L),已成功应用于实际水样中BrO₃^-的高灵敏快速定量检测。     

基于钯纳米颗粒修饰直立碳纳米管电极的电化学葡萄糖生物传感器

将电化学氧化生成的Pd(Ⅳ)离子配合到直立碳纳米管(ACNTs)上, 使其还原为纳米颗粒(Pb nps), 从而制得Pd nps-ACNTs纳米复合物电极, 经过葡萄糖氧化酶(GOD)进一步修饰后, 制成GOD/Pds nps/ACNTs酶电极, 通过测量GOD和葡萄糖酶促反应中产生的H₂O₂含量, 进而监测葡萄糖浓度. 实验结果表明, 电极表面大量Pd纳米颗粒的存在显著提高了传感器的检测灵敏度, 使酶电极具有响应时间短(<5 s)及检测电位低(<0.4 V)等优点.     

羧基化碳纳米管修饰的安培型葡萄糖传感器测定血液中葡萄糖

在临床医学、生物过程、食品工业中葡萄糖的分析测定一直都占有重要地位。葡萄糖的测定以分光光度法[1]和酶电极法[2]为主。光度法的灵敏度和准确度低,选择性差。第一代酶电极通常采用分子氧作为电子媒介体,但此法背景电流大,易受环境中分子氧浓度的影响。逐渐发展起来的第二代     

基于Nafion/碳纳米粒子修饰的葡萄糖传感器

采用滴涂法制备了Nafion/碳纳米粒子复合物修饰玻碳电极,该电极对H2O2具有良好的电催化氧化性能。还利用滴涂法制备了Nafion/碳纳米粒子复合物包裹的葡萄糖酶电化学生物传感器,该生物传感器对葡萄糖有着良好的电催化作用。应用该传感器对葡萄糖进行了检测,检测线性范围为2.0×10-6～6.0×10-3mol/L,检出限为1.6×10-6mol/L(S/N=3),实验结果表明该传感器具有良好的稳定性、重现性和抗干扰能力。对小鼠血清样品中的葡萄糖进行检测,结果令人满意。     

溶胶-凝胶法制备的介体型电流式葡萄糖生物传感器

以戊二醛为交联剂，将葡萄糖氧化酶（GOD）和介体甲苯胺蓝（TBO）通过共价键作用固定于铂电极表面上的溶胶－凝胶薄膜载体上，制成了葡萄糖生物传感器；该功能化薄膜由γ－氨丙基甲基二甲氧基硅烷和四甲氧基硅在稀盐酸催化作用下通过水解－缩聚反应制得；红外光谱证实，GOD和TBO在载体上的固定化是通过交联剂分子上的醛基与GOD、TBO和载体上的氨基反应实现的，共价交联方式有效地避免了酶和介体从载体上的脱落；葡萄糖生物传感器的循环伏安特性表明，TBO能在GOD反应活性中心与铂电极表面之间进行有效的电子传递；葡萄糖生物传感器对底物葡萄糖响应的线性范围是1－8mmol/L，检出限是0．05mmol/L，寿命超过1个月。     

基于立方体纳米氧化亚铜修饰的安培型葡萄糖生物传感器的制备及性能研究

将合成的立方体纳米氧化亚铜用于修饰玻碳电极,在其上固定葡萄糖氧化酶,构建了高灵敏的安培型葡萄糖生物传感器.采用X射线衍射(X RD)、扫描电镜(SEM)对合成的立方体纳米氧化亚铜及其修饰电极进行了表征.结果表明,合成的纳米氧化亚铜为均匀的立方体形状.采用循环伏安法(CV)、交流阻抗谱(EIS)、差分脉冲伏安法(DPV)及计时电流法(CA)考察了修饰电极的电化学行为.在含0.1 mmol/L葡萄糖的磷酸盐缓冲溶液(pH 7.4)中研究了立方体纳米氧化亚铜修饰电极的循环伏安(CV)响应,实验结果表明,此修饰电极对葡萄糖显示出良好的电催化性能.DPV响应电流与葡萄糖的浓度在5.0×10-6 ～4.0× 10-3mol/L范围内呈良好的线性关系,线性相关系数R2=0.9983,检出限为6.8×10-7 mol/L(S/N=3).CA实验结果表明,尿酸、抗坏血酸、D-果糖对传感器不产生干扰.本传感器具有较好的重现性和稳定性,可用于实际样品中葡萄糖的检测.     

Amperometric Glucose Biosensor Based on Glucose Oxidase Encapsulated in Carbon Nanotube–Titania–Nafion Composite Film on Platinized Glassy Carbon Electrode

A highly sensitive and selective glucose biosensor has been developed based on immobilization of glucose oxidase within mesoporous carbon nanotube–titania–Nafion composite film coated on a platinized glassy carbon electrode. Synergistic electrocatalytic activity of carbon nanotubes and electrodeposited platinum nanoparticles on electrode surface resulted in an efficient reduction of hydrogen peroxide, allowing the sensitive and selective quantitation of glucose by the direct reduction of enzymatically‐liberated hydrogen peroxide at ?0.1 V versus Ag/AgCl (3 M NaCl) without a mediator. The present biosensor responded linearly to glucose in the wide concentration range from 5.0×10^?5 to 5.0×10^?3 M with a good sensitivity of 154 mA M^?1cm^?2. Due to the mesoporous nature of CNT–titania–Nafion composite film, the present biosensor exhibited very fast response time within 2 s. In addition, the present biosensor did not show any interference from large excess of ascorbic acid and uric acid.     

Amperometric Glucose Biosensor Based on the Deposition of Copper and Glucose Oxidase onto Glassy Carbon Transducer

ABSTRACT

The performance of a first generation glucose amperometric biosensor based on the entrapment of glucose oxidase (GOx) within a net of copper electrodeposited onto activated glassy carbon electrode, is described. The copper electrodeposited offers an efficient electrocatalytic activity towards the reduction of enzymatically-liberated hydrogen peroxide, allowing for a fast and sensitive glucose quantification. The influence of the electrodeposition conditions (pH, potential, time, copper salt and enzyme concentrations) on the response of the bioelectrode was evaluated from the amperometric signals of hydrogen peroxide and glucose. The combination of copper electrodeposition with a nation membrane allows an excellent selectivity towards easily oxidizable compounds such as uric and ascorbic acids at an operating potential of -0.050 V. The response is linear up to 2.0 × 10^?2 M glucose, the detection limit being 1.2 × 10^?3 M.     

Amperometric Glucose Biosensing of Gold Nanoparticles and Carbon Nanotube Multilayer Membranes

A novel multilayer gold nanoparticles/multiwalled carbon nanotubes/glucose oxidase membrane was prepared by electrostatic assembly using positively charged poly(dimethyldiallylammonium chloride) to connect them layer by layer. The modification process and membrane structures were characterized by atomic force microscopy, scanning electron microscopy and electrochemical methods. This membrane showed excellent electrocatalytic character for glucose biosensing at a relatively low potential (?0.2 V). The K_m value of the immobilized glucose oxidase was 10.6 mM. This resulting sensor could detect glucose up to 9.0 mM with a detection limit of 128 μM and showed excellent analytical performance.     

Highly Selective and Sensitive Amperometric Biosensing of Glucose at Ruthenium-Dispersed Carbon Paste Enzyme Electrodes

Abstract

The selectivity and sensitivity of glucose measurements at carbon-paste based amperometric biosensors are greatly enhanced through the use of ruthenium-dispersed graphite particles. The improved performance is attributed to the substantial lowering of the overvoltage for the reduction of the hydrogen peroxide product. Hence, cathodic measurements of glucose can be caried out at an optimal potential range (-0.15 to +0.20 V). Contributions from easily oxidizable substances (e.g. acetaminophen, ascorbic and uric acids) are eliminated, without the need for mediators or membrane barriers. The electrocatalytic action of the ruthenium sites results also in a substantially improved sensitivity. A fast flow injection operation is illustrated.     

Amperometric Glucose Biosensor Based on Platinum Nanoparticles Combined Aligned Carbon Nanotubes Electrode

A sensitive amperometric glucose biosensor based on platinum nanoparticles (PtNPs) combined aligned carbon nanotubes (ACNTs) electrode was investigated. PtNPs which can enhance the electrocatalytic activity of the electrode for electrooxidating hydrogen peroxide by enzymatic reaction were electrocrystallized on 4‐aminobenzene monolayer‐grafted ACNTs electrode by potential‐step method. These PtNPs combined ACNTs' (PtNPs/ACNTs) surfaces were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The highly dispersed PtNPs on ACNTs can be obtained. The enzyme electrode exhibits excellent response performance to glucose with linear range from 1×10^?5–7×10^?3 mol L^?1 and fast response time within 5 s. Furthermore, this glucose biosensor also has good reproducibility. It is demonstrated that the PtNPs/ACNTs electrode with high electrocatalytic activity is a suitable basic electrode for preparing enzyme electrodes.