层层自组装制备基于多壁碳纳米管的胆碱生物传感器

以经混酸处理的多壁碳纳米管(MWCNTs)修饰铂(Pt)电极,在此基础上固定(PAA/PVS)3复合膜,采用层层自组装技术将高分子聚电解质PDDA与胆碱氧化酶交替组装在已修饰的电极上,构建了电流型胆碱生物传感器。实验结果表明,MWCNTs的引入使电极对H2O2的催化电流明显增大,制成的酶电极可以有效控制酶量的使用,酶膜组装层数为8时最优,对胆碱的线性响应范围为5×10-7～1×10-4mol/L;灵敏度为12.53μA/mmol;响应时间为7.60s;检出限为2×10-7mol/L(S/N=3)。传感器的抗干扰能力强,稳定性好,30d时的响应电流值仍保持最初的89.5%。3次平行实验的RSD为3.64%。     

层层自组装技术制备PDDA-多壁碳纳米管-胆碱生物传感器

以PDDA分散多壁碳纳米管(MWCNTs),制得PDDA-MWCNTs悬浮液,采用层层自组装技术将PDDA-MWCNTs与胆碱氧化酶(ChOx)交替组装在铂(Pt)电极上,最后滴加Nafion制备抗干扰膜,构建了电流型胆碱生物传感器。实验结果表明,构建的复合酶膜(PDDA-MWCNTs/ChOx)n对底物胆碱的催化电流随着组装层数增多而明显增大,酶膜组装6层时最优。此传感器在5×10-6～2.5×10-4mol/L浓度范围内对胆碱有良好线性范围,响应时间为6.6s;灵敏度为21.97μA/mmol;检出限为2×10-6mol/L(S/N=3),RSD<5%,且传感器抗干扰能力强、稳定性好。     

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)

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。     

新型多壁碳纳米管/白藜芦醇印迹溶胶-凝胶层层组装电化学传感器研究

采用电化学沉积方法将印迹溶胶-凝胶膜沉积到功能化碳纳米管(MWNT-COOH)修饰的碳电极表面,成功研制一种新型多壁碳纳米管/白藜芦醇印迹溶胶-凝胶电化学传感器.采用扫描电镜(SEM),循环伏安法(CV),方波伏安法(SWV)和计时电流法(i-t)详细考察该印迹溶胶-凝胶膜的形态和电化学性能.结果表明该传感器对白藜芦醇具有较高的选择性和亲和性.与无多壁碳纳米管修饰的印迹传感器比较,MWNT层修饰的印迹传感器电流响应信号明显提高.白藜芦醇与印迹溶胶-凝胶膜的特异性结合使该传感器的电流发生变化,电流变化与白藜芦醇浓度在5.0×10-7～8.0×10-5mol?L-1范围内呈良好线性关系,检测限为5.1×10-8mol?L-1,该传感器成功应用于葡萄酒中白藜芦醇含量的检测.     

多壁碳纳米管功能化及其在电化学葡萄糖传感器中的应用

利用硅烷偶联剂的表面修饰技术,将氨基丙基三乙氧基硅烷(APS)共价接枝到酸处理后的碳纳米管的表面.红外光谱数据证实了该反应的可行性.修饰后的碳纳米管在水中具有良好的分散性.利用西夫碱反应将氨基化的碳纳米管与醛基化的葡萄糖氧化酶共价层层自组装到电极表面,获得灵敏度可控的葡萄糖传感器.用电化学交流阻抗法和扫描电镜对成膜过程...     

基于聚锂均苯三甲酸/多壁碳纳米管复合膜的葡萄糖生物传感器的研究

利用电聚合方法在裸玻碳(GC)电极上修饰一种新型金属有机框架化合物锂均苯三甲酸(Li-BTC),并采用滴涂技术制备了Nafion/GOx/MWNTs/poly-Li-BTC/GC葡萄糖生物传感器。利用扫描电镜分析了复合膜(含MWNTs和poly-Li-BTC)的形貌,采用循环伏安和交流阻抗方法对修饰电极的电化学性能进行了研究。结果表明,此复合膜可增大裸玻碳电极的有效表面积、改善电极的电催化活性。利用循环伏安法和计时安培法研究了葡萄糖在Nafion/GOx/MWNTs/poly-Li-BTC/GC电极上的电化学特性。结果表明:葡萄糖的浓度在0.02～1.56 mmol/L范围内,此修饰电极的电流响应与葡萄糖的浓度呈线性关系,其相关系数为0.9992,检出限为5.1μmol/L(信噪比为3∶1)。修饰电极的米氏常数为0.832 mmol/L,回收率为96.3#～100.3#。本研究制备的葡萄糖生物传感器具有较好的重复性、重现性、选择性与稳定性,用于葡萄糖注射液中葡萄糖含量的检测,结果满意。     

利用层层累积技术制备基于纳米碳管的葡萄糖生物传感器

以多壁纳米碳管(MWNTS)为电子媒介体和酶的吸附载体,利用层层累积的自组装技术固定葡萄糖氧化酶(GOX)的多层(MWNTa/GOx).复合薄膜修饰电极,制备了一种新型葡萄糖生物传感器.结果表明,传感器对葡萄糖的响应电流值随着MWNTa//GOx复合薄膜层数的不同而变化,当MWNTa//GOx复合薄膜的层教为6时,响应电流值迭到最大.(MWNTs/GOx).复合薄膜修饰的葡萄糖生物传感器对30mmol/L葡萄糖的响应电流为1.63μA,响应时间仅为6.7 s.该生物传感器检测的线性范围为0.5～15 mmol/L,最低检测浓度可达0.09 mmol/L.     

基于层层组装钴铝水滑石/聚电解质包裹碳纳米管的无酶葡萄糖传感器

采用共沉淀法合成了钴铝水滑石(CoAl-LDH),将CoAl-LDH与PSS包裹的CNTs(CNTs@PSS)通过层层自组装法构筑CNTs@PSS/CoAl-LDH多层膜电极,并将其应用于葡萄糖的分析测定。X射线衍射光谱、红外光谱和SEM表明:共沉淀法合成的CoAl-LDH具有典型的水滑石特征峰及形貌。电化学阻抗谱表明:CoAl-LDH可与CNTs@PSS均匀有效地组装构筑多层膜。电化学研究表明:CNTs的引入很好地提高了CoAl-LDH修饰电极的灵敏度。研究结果表明该传感器对葡萄糖在3.0×10-6～4.98×10-4mol/L范围内呈良好的线性响应,灵敏度为1.03×10-3A.L/mol。     

一种基于巯基化聚丙烯胺自组装膜的免疫传感器固定方法

提出了一种基于巯基自组装的新型蛋白质固定化方法。应用偶联试剂碳二亚胺(EDC)和N-羟基琥珀酰亚胺(NHS)使聚丙烯胺盐酸盐(PAH)与3-巯基丙酸(MPA)偶合，在石英晶振表面自组装，形成一带多氨基的巯基自组装膜。应用该方法成功地固定了羊抗人IgM抗体，并用于人血清免疫球蛋白M(IgM)的测定。详细考察了自组装条件、抗体包被和免疫反应的主要实验条件以及传感器的响应性能。与MPA法比较，应用该方法可在传感器表面固定更多的抗体分子，传感器的响应灵敏度亦更好。在优化的实验条件下，反应的线性范围0．66-26．4mg／L；回归方程Y=92．44 12．40X；相关系数r=0．9920。     

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。     

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.     

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.     

Avidin and Glucose Oxidase‐non‐covalently Functionalized Multi‐walled Carbon Nanotubes: A New Analytical Tool for Building a Bienzymatic Glucose Biosensor

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.     

A New Application of Carbon Nanotubes Constructing Biosensor

Carbon nanotubes used for constructing biosensor was described for the first time. Single-wall carbon nanotubes (SWNTs) functionalized with carboxylic acid groups were used to immobilize glucose oxidase forming a glucose biosensor. The biosensor response can be determined by amperometric method at a low applied potential (0.40V).     

Spatial Architecture of Modified Carbon Nanotubes/Electrochemically Reduced Graphene Oxide Nanomaterial for Fast Electron Transfer. Application in Glucose Biosensor

Electron transfer (ET) reactions in bioelectrocatalysis of enzymes at electrode surfaces require not only the efficient immobilization, but also highly conductive nanostructured platform, which allows for retaining its bioactivity and structural conformation. The novel architecture of spatially separated electrochemically reduced graphene oxide (ERGO) by multi‐walled carbon nanotubes functionalized with 4‐(pyrrole‐1‐yl) benzoic acid (MWCNT/PyBA) with the accurate porous structure could be an alternative for earlier approaches to the construction of bioelectrocatalytic systems with rapid diffusion of reagents from the solution to the enzyme molecule. The formation of ERGO/MWCNT/PyBA system was confirmed by electrochemical, spectroscopic and microscopic methods. The cyclic voltammetry experiments revealed that the presence of ERGO in the conductive material affects the electronic communication between the enzyme molecule and modified electrode surface greatly improving its ET properties resulting in a double increase of the heterogeneous ET rate constant value (k_s=6.5 s^?1). The fabricated glucose oxidase based biosensor sensitively detects glucose, therefore, ERGO/MWCNT/PyBA architecture could provide a novel and efficient platform for immobilization of redox enzymes.     

含金属纳米粒子的层层自组装及单壁碳纳米管的催化生长

利用层间的静电吸附作用，重氮树脂和不同种类的含金属纳米粒子被依次吸附到硅片表面形成层层自组装膜。通过改变自组装膜的层数可以控制纳米粒子在表面吸附的量，同时利用重氮树脂的光敏特性可以实现纳米粒子在表面的图案化排布。以这些纳米粒子为催化剂，研究了单壁碳纳米管在硅片表面的化学气相沉积生长。