Amperometric Glucose Biosensor Based on Ultrafine Platinum Nanoparticles

Abstract

In the present paper the ultrafine and highly dispersed platinum nanoparticles (average size 3 nm) were used for the construction of a glucose biosensor in a simple method. An excellent response to glucose has been obtained with a high sensitivity (137.7 µA mM^?1 cm^?2) and fast response time (5 s). The biosensor showed a detection limit of 5 µM (at the ratio of signal to noise, S/N=3) and a linear range form 0.2 to 3.2 mM with a correlation coefficient r=0.999. The apparent Michaelis–Menten constant (k _m) and the maximum current were estimated to be 9.36 and 1.507 mA mM^?1 cm^?2, respectively. In addition, effects of pH value, applied potential and the interferents on the amperometric response of the sensor were investigated and discussed.     

基于碳纳米管和铁氰酸镍纳米颗粒协同作用的葡萄糖生物传感器

将制备的铁氰酸镍纳米颗粒(NiNP)与多壁碳纳米管(CNT)混合, 分散于壳聚糖溶液中, 形成一种新的纳米复合成分(NiNP-CNT-CHIT), 将其修饰在玻碳电极表面. 新复合膜体现了NiNP和CNT之间的协同作用, 由于CNT的良好的传递电子性能, 促使NiNP催化氧化还原能力有了较大的提高. 此NiNP-CNT-CHIT复合膜修饰的玻碳电极在较低电位下对过氧化氢具有良好的电催化性能, 与NiNP-CHIT膜比较, 测定H₂O₂的灵敏度增大了50倍. 通过戊二醛在电极表面固定葡萄糖氧化酶制备了一种新的葡萄糖传感器. 该传感器在－0.2 V下对葡萄糖的线性范围为0.05～10 mmol/L, 检测下限为10 μmol/L.     

基于纳米金和硫堇固定酶的过氧化氢生物传感器

在铂电极上自组装一层纳米金(GNs), 构建负电荷的界面, 然后通过金-硫、金-氮共价键合作用和静电吸附作用自组装一层阳离子电子媒介体硫堇(Thio). 再以同样的作用自组装一层GNs和辣根过氧化酶(HRP)的混合物, 最后在电极最外层滴加一层疏水性聚合物壳聚糖(Chit), 由此制备了一种新型的过氧化氢生物传感器. 研究了工作电位、检测底液pH、温度对响应电流的影响, 以及GNs和HRP之间的相互作用, 探讨了传感器的表面形态、交流阻抗、重现性和稳定性. 该传感器的酶催化反应活化能为12.4 kJ/mol, 表观米氏常数为6.5×10^－4 mo/L, 在优化的实验条件下, 所研制的传感器对H₂O₂的线性范围为5.6×10^－5～2.6×10^－3 mol/L, 检出限为1.5×10^－5 mol/L. 应用此方法制备了HRP和葡萄糖氧化酶(GOD)双酶体系葡萄糖生物传感器, 并应用于实验样品葡萄糖含量的测定.     

A Novel Potentiometric Glucose Biosensor Based on Polyaniline Semiconductor Films

Abstract

Application of polyaniline semiconductor films to potentiometric biosensor development provides certain advantages comparing with the known systems. Using self-doped polyaniline instead of common polymer as pH transducer the stable potentiometric response of 70 mV/pH was obtained. Taking as an example glucose biosensor we showed that polyaniline based electrode possessed three-four fold increased potential shift than glucose-sensitive field-effect transistor did. One can increase the sensitivity of potentiometric biosensor using thick ion-exchange membranes (in our case Nafion) in order to concentrate product near electrode surface. Such sensor possessed higher response time.     

光照纳米银颗粒对葡萄糖生物传感器响应电流的抑制

采用纳米银-壳聚糖复合膜固定葡萄糖氧化酶,构建葡萄糖生物传感器.利用计时电流法对不同光照时间纳米银颗粒组装的酶电极响应电流进行了表征.实验结果表明,光照纳米银颗粒可以抑制葡萄糖生物传感器的响应电流;随着光照时间的延长,纳米银颗粒的抑制作用逐渐增强,当光照时间达到120min时,葡萄糖生物传感器的响应电流最小(-3.953μA/cm²).葡萄糖生物传感器响应电流的抑制可能是由纳米银颗粒表面的Ag⁺离子浓度及表面性能的变化引起的.     

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.     

纳米ZnO增强葡萄糖生物传感器的制备和应用

为提高葡萄糖生物传感器的灵敏度,以纳米ZnO与聚乙烯醇缩丁醛(PVB)构成复合固定酶膜基质,采用溶胶-凝胶法固定葡萄糖氧化酶(GOD),用戊二醛进行交联,制成葡萄糖生物传感器。实验结果表明,GOD可牢固地固定在电极表面,在相同葡萄糖浓度下,加入纳米颗粒的电极的电流响应值比未加颗粒的高约100倍,电极重复使用46次后电流响应值仅下降到初始的70%。电极制备方法简单,易于操作。同时对温度、溶液pH值以及溶剂对电极的影响进行了研究,获得了最优的实验条件。     

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。     

一种基于壳聚糖固定葡萄糖氧化酶的葡萄糖生物传感器的研究

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。     

纳米铂颗粒修饰薄膜金电极的新型葡萄糖传感器研究

在没有引入电子媒介体条件下,为了提高传感器的响应灵敏度,降低工作电位,利用电化学沉积法在薄膜金电极表面修饰纳米铂颗粒,并通过戊二醛固定酶的方法制备了一种新型生物传感器。研究了在薄膜金电极上修饰纳米铂颗粒前后传感器对低浓度葡萄糖的响应影响。结果表明,纳米铂颗粒修饰后所制备的葡萄糖传感器工作电位下降为0.4 V,测定葡萄糖的检出限从100μmol/L下降到10μmol/L。传感器对10~1300μmol/L低浓度葡萄糖的响应灵敏度为50.8 nA/(cm2μmol/L);响应时间30 s;r为0.9974;传感器精密度为2.1%,并具有较好的稳定性。     

纳米金胶增强葡萄糖生物传感器的构建

将纳米金胶(AuNPs)和羟基磷灰石(HAp)按一定比例混合制备了新型复合膜用于葡萄糖氧化酶(GOD)的固定,构建了高灵敏的葡萄糖传感器。由于纳米金胶的存在,葡萄糖氧化酶的直接电化学性质得以增强,在去除氧气的PBS(pH 7.0)介质中,固定在复合膜内的GOD表现出一对良好的氧化还原峰。在饱和氧气条件下,当加入一定量的葡萄糖时,由于GOD催化葡萄糖氧化消耗溶液中的溶解氧,-0.8 V处溶解氧的还原峰电流降低,且峰电流降低的量与葡萄糖浓度在0.02～1.62 mmol/L范围内呈线性相关,检出限为5.0μmol/L,检测灵敏度达9.91 mA.mol-1.L,可实现对葡萄糖的快速检测。     

Glucose Biosensor Based on the Use of a Carbon Nanotube Paste Electrode Modified with Metallic Particles

This work reports on the performance of new glucose biosensors based on the combination of the electrocatalytic properties of metals and carbon nanotubes towards the reduction of hydrogen peroxide with the biocatalytic activity of glucose oxidase (GOx). The bioelectrodes were obtained by dispersing the metal particles, enzyme and multi-wall carbon nanotubes within a mineral oil binder. The strong electrocatalytic activity of copper and iridium towards the reduction of hydrogen peroxide has made possible an important improvement in the sensitivity for the determination of glucose compared to the carbon nanotube composite without metals. A highly sensitive and selective amperometric detection of glucose becomes possible at very low potentials (−0.100 V). The presence of the protein enables a better dispersion of the metals within the composite matrix, thus allowing an additional enhancement in the response to hydrogen peroxide. The influence of the amount of copper in the composite on the analytical performance of the bioelectrode is discussed. A biosensor containing 0.77% w/w Cu and 10.0% w/w GOx gave a fast response (10.0 s), a linear relationship between current and glucose concentration up to 1.20 × 10⁻² M, and a detection limit of 2.0 × 10⁻⁵ M. A similar behavior was found for a carbon nanotube-composite electrode containing iridium.     

超细银－金复合颗粒增强酶生物传感器的研究

用琥珀酸二异辛酯磺酸钠／环已烷反胶束体系合成憎水纳米银－金复合颗粒， 并用此纳米银－金颗粒与聚乙烯醇缩丁醛构成复合固酶模基质，用溶胶－凝胶法固 定葡萄糖氧化酶，构建葡萄糖生物传感器。实验表明，纳米憎水银－金颗粒可以大 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几万纳安。探 讨了纳米颗粒效应在固定化酶中所起的作用，为纳米颗粒在生物传感器领域中的应 用提供了可参考的实验和理论依据。     

氮、铁共掺杂碳纳米粒子的制备及在过氧化氢和葡萄糖检测中的应用

以L-酒石酸和一水柠檬酸为混合碳源,以乙二胺为氮源和聚合试剂,并添加六水三氯化铁,通过一锅溶剂热法合成了氮、铁共掺杂碳纳米粒子(N/Fe-CNPs),采用制备的N/Fe-CNPs模拟过氧化物酶催化过氧化氢(H₂O₂)氧化3,3',5,5'-四甲基 产生可溶性的蓝色产物,联合葡萄糖氧化酶建立了测定H₂O₂和葡萄糖含量的新方法。 结果显示:H₂O₂及葡萄糖的浓度与反应体系的吸光度呈良好的线性关系,H₂O₂的线性范围为0.2~20 μmol/L,葡萄糖的线性范围为0.1~1.0及1.0~80 μmol/L,最低检出限分别可达42.5和76.1 nmol/L。     

New Nanocomposite Based on Prussian Blue Nanoparticles/Carbon Nanotubes/Chitosan and Its Application for Assembling of Amperometric Glucose Biosensor

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.     

Glucose Biosensor Based on Silicon Nitride Nanoparticles

For the first time silicon nitride (Si₃N₄) nanoparticles was used for preparation electrochemical biosensor. GOx immobilized on the Si₃N₄ nanoparticles exhibits facile and direct electrochemistry. The surface coverage and heterogeneous electron transfer rate constant (k_s) of immobilized GOx were 6.3×10^?13 mol cm^?2 and 47.4±0.3 s^?1. The sensitivity, linear concentration range and detection limit of the biosensor for glucose detection were 38.57 µA mM^?1 cm^?2, 25 µM to 8 mM and 6.5 µM, respectively. This biosensor also exhibits good stability, reproducibility and long life time. These indicate Si₃N₄ nanoparticles is good candidate material for construction of third generation biosensor and bioelectronics devices.     

新型磁性纳米电化学DNA生物传感器的研究

利用高分子磁性纳米粒子有效地将磁性分离、富集和化学修饰电极的电化学检测相结合,构建以亚甲基蓝为嵌入式杂交指示剂的电化学DNA生物传感器.此传感器对碱基错配的序列有较好的选择性.传感器对目标序列的响应在1×10-13～1×10-6 mol/L范围内呈线性关系;检出限为4.3×10-14 mol/L.这种新型的高分子磁性纳米粒子电化学DNA生物传感器具有高的灵敏度,其线性范围宽,成本低,为DNA的痕量分析提供了一种新的思路.