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1.
Developing enzyme-free sensors with high sensitivity and selectivity for H2O2 and glucose is highly desirable for biological science.Especially,it is attractive to exploit noble-metal-free nanomaterials with large surface area and good conductivity as highly active and selective catalysts for molecular detection in enzyme-free sensors.Herein,we successfully fabricate hollow frameworks of Co3O4/N-doped carbon nanotubes(Co3O4/NCNTs)hybrids by the pyrolysis of metal-organic frameworks followed by calcination in the air.The as-prepared novel hollow Co3O4/NCNTs hybrids exhibit excellent electrochemical performance for H2O2 reduction in neutral solutions and glucose oxidation in alkaline solutions.As sensor electrode,the Co3O4/NCNTs show excellent non-enzymatic sensing ability towards H2O2 response with a sensitivity of 87.40μA(mmol/L)^-1 cm^-2,a linear range of 5.00μmol/L-11.00 mmol/L,and a detection limitation of 1μmol/L in H2O2 detection,and a good glucose detection performance with 5μmol/L.These excellent electrochemical performances endow the hollow Co3O4/NCNTs as promising alternative to enzymes in the biological applications. 相似文献
2.
A simple and efficient colorimetric biosensing for hydrogen peroxide and glucose with peroxidase-like vitamin C(Vc) functionalized Fe3O4 magnetic nanoparticles(Vc/Fe3O4MNPs) as a catalyst is reported. Compared with Fe3O4 MNPs and other catalysts, Vc/Fe3O4 MNPs exhibited superior catalytic properties. Kinetic studies indicated that vitamin C incorporated on Fe3O4 MNPs improved the affinity toward H2O2. As low as 0.29 μmol/L H2O2 can be detected with a wide linear range of 0.5—100 μmol/L H2O2; moreover, as low as 0.288 μmol/L glucose can be detected with a linear range of 0.5—25 μmol/L glucose. The detection method was highly sensitive in sensing H2O2 and glucose. The robustness of Vc/Fe3O4 MNPs rendered them suitable for wide ranging applications. 相似文献
3.
Ag nanoparticles were prepared by using the ion-exchange of Nafion combined with electrochemical reduction on the electrode. Ag nanoparticles are highly dispersed in Nafion film with an average size of 4.0±0.2 nm.The amount of Ag nanoparticles can be readily controlled by the amount of Nafion coated on the electrode.Thus obtained Ag nanoparticles exhibit good catalytic activity for the reduction of H2O2 with a linear response to H2O2 in the concentration range of 0.04-8.0 mmol/L with a sensitivity of 0.34μA/mmol/L and a detection limit of 1.0×10-8 mol/L. 相似文献
4.
A cobalt nanoparticles-attached indium tin oxide(CoNPs/ITO) electrode was applied to the immobilization of hemoglobin(Hb) and an Hb modified CoNPs/ITO electrode(Hb/CoNPs/ITO) was prepared. The direct electron transfer of Hb was shown by the well-behaved voltammetric responses for Hb/CoNPs/ITO electrode and the effects of scan rate and pH value were observed. Based on the catalytic activity of Hb immobilized on the CoNPs/ITO electrode toward the reduction of H2O2, a mediator-free H2O2 sensor was developed. A linear relationship existed between the catalytic current and the H2O2 concentration in a range of 1.0―100.0 μmol/L with a detection limit (S/N=3) of 0.2 μmol/L. 相似文献
5.
通过溶胶-凝胶法制备的Imm-Fe3+-IL纳米材料具有类过氧化物酶的活性,能够催化过氧化氢(H2O2)快速氧化3,3′,5,5′-四甲基联苯胺(TMB)产生相应的颜色变化。 稳态动力学分析表明,Imm-Fe3+-IL纳米材料遵循典型的Michaelis-Menten模型和乒乓机理。 辣根过氧化物酶(HRP)相比,Imm-Fe3+-IL纳米材料纳米材料具有更强的亲和性。 联合葡萄糖氧化酶建立了H2O2和葡萄糖的比色检测方法。 结果显示:H2O2和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1~200 μmol/L,葡萄糖的线性范围为10~200 μmol/L,最低检出限(LOD)分别为0.35和3.31 μmol/L。 相似文献
6.
Nanocomposite of Co3O4 and MCNT was synthesised using one step solvothermal method, and an electrochemical non-enzymatic glucose sensor (Co3O4-MCNT/GCE) was successfully constructed. This sensor was used successfully for the quantitative analysis of trace glucose in serum sample. 相似文献
7.
采用表面印迹技术,以磁性二氧化硅纳米粒子(Fe3O4@SiO2 NPs)作为载体、血红蛋白(Hb)为模板分子、正硅酸乙酯(TEOS)为印迹聚合物单体,制备了Hb印迹Fe3O4@SiO2的磁性印迹纳米粒子(MMIPs NPs). MMIPs NPs具有磁性内核和血红蛋白印迹壳层的核壳结构,可以富集并固定Hb. 使用壳聚糖将MMIPs NPs固定于磁性电极表面,构建血红蛋白类酶生物传感器,研究了Hb对过氧化氢(H2O2)的催化活性. MMIPS NPS相比于磁性非印迹纳米粒子(MNIPS NPS),催化电流增加了14.3%. 采用磁性电极,MMIPS NPS、Hb和O2的顺磁性使得该类酶生物传感器对H2O2的催化电流增加了60.0%. 血红蛋白类酶生物传感器电流响应与H2O2浓度在25 ~ 200 μmol·L-1间呈线性关系,检出限为3 μmol·L-1(S/N=3),表明该类酶传感器对H2O2具有良好的催化性能. 相似文献
8.
In the present work, WO3 nanosheets(WO3 NSs) were prepared by a facile method at room temperature. The obtained WO3 NSs showed peroxidase-like activity, which could catalyze 3,3',5,5'-tetramethylbenzidine(TMB) to form a blue oxidation product(ox TMB) in the presence of H2O2. Based on this, convenient and sensitive colorimetric methods for the detection of H2O2 and glucose were established. The linear ranges for detecting H2O2 and glucose were 1-200 μmol/L and 1-100 μmol/L, respectively. The limits of the detection of H2O2 and glucose were as low as 0.79 and 0.96 μmol/L, respectively. This method was also successfully applied to the detection of glucose in urine samples. The detection result was consistent with that of the value detected by the clinical method, indicating the potential in clinical diagnosis and biomedical detection. 相似文献
9.
Wei Liu Chaojun Lei Hongxiu Zhang Xiaolin Wu Qing Jia Denghong He Bin Yang Zhongjian Li Yang Hou Lecheng Lei Xingwang Zhang 《中国化学快报》2017,28(6):1306-1311
In this study,a non-enzymatic hydrogen peroxide sensor was successfully fabricated on the basis of copper sulfide nanoparticles/reduced graphene oxide(CuS/RGO) electrocatalyst.Using thiourea as reducing agent and sulfur donor,CuS/RGO hybrid was synthesized through a facile one-pot hydrothermal method,where the reduction of GO and deposition of CuS nanoparticles on RGO occur simultaneously.The results confirmed that the CuS/RGO hybrid helps to prevent the aggregation of CuS nanoparticles.Electrochemical investigation showed that the as-prepared hydrogen peroxide sensor exhibited a low detection limit of 0.18μmol/L(S/N = 3),a good reproducibility(relative standard deviation(RSD) of4.21%),a wide linear range(from 3 to 1215 μmol/L) with a sensitivity of 216.9 μA L/mmol/cm~2 under the optimal conditions.Moreover,the as-prepared sensor also showed excellent selectivity and stability for hydrogen peroxide detection.The excellent performance of CuS/RGO hybrid,especially the lower detection limit than certain enzymes and noble metal nanomaterials ever reported,makes it a promising candidate for non-enzymatic H_2O_2 sensors. 相似文献
10.
A magnetic sensor for detection of Pb~(2+) has been developed based on Fe/Fe_3O_4 nanoparticles modified by3-(3,4-dihydroxyphenyl)propionic acid(DHCA). The carboxyl groups of DHCA have a strong affinity to coordination behavior of Pb~(2+) thus inducing the transformation of Fe/Fe_3O_4 nanoparticles from a dispersed to an aggregated state with a corresponding decrease, then increase in transverse relaxation time(T_2) of the surrounding water protons. Upon addition of the different concentrations of Pb~(2+) to an aq. solution of DHCA functionalized Fe/Fe_3O_4 nanoparticles(DHCA-Fe/Fe_3O_4 NPs)([Fe] = 90 mmol/L), the change of T_2 values display a good linear relationship with the concentration of Pb~(2+) from 40 μmol/L to 100 μmol/L and from 130 μmol/L to 200 μmol/L, respectively. Owing to the especially strong interaction between DHCA and Pb~(2+), DHCA-Fe/Fe_3O_4 NPs exhibited a high selectivity over other metal ions. 相似文献
11.
基于层状二硫化钼纳米片比色检测亚锡离子 总被引:1,自引:0,他引:1
在醋酸/醋酸钠缓冲溶液(pH=4.5)中, 亚锡离子对层状二硫化钼(MoS2)纳米片催化过氧化氢(H2O2)氧化邻苯二胺(OPD)的显色反应有很强的抑制作用, 据此构建了一种检测亚锡离子的比色传感器. 实验结果表明, 与不加MoS2纳米片的OPD/H2O2比色传感体系相比, MoS2/OPD/H2O2体系检测亚锡离子的灵敏度显著提高, 线性范围变宽. 在优化的条件下, MoS2/OPD/H2O2传感体系检测亚锡离子的线性范围为0.02~3.0 μmol/L, 检出限为8 nmol/L (S/N=3). 该传感体系对检测亚锡离子具有高的选择性, 可用于湖水中亚锡离子的检测. 相似文献
12.
HeterojunctionFe_2O_3 nanoparticles(NPs), NiFe_2O_4 nanofibers(NFs), and CoFe_2O_4 NFs were synthesized by electrospinning and the subsequent thermal treatment processes. Characterization results indeed display the three-dimensional net-like textural structures of these as-electrospun spinel-type MFe_2O_4 NFs. The MFe_2O_4 NFs-based film configurations possess abundant micro/meso/macropores on their surface. These structures could afford more accessible transport channels for effective reduction of the mass transport resistance and improvement of the density of exposed catalytic active sites. All these advantages are responsible for the enhanced electro-catalytic performance of these MFe_2O_4 NFs in hydrazine oxidation. When used for hydrazine detection, CoFe_2O_4 NFs show the best catalytic efficiency.For example, the CoFe_2O_4 NFs possess a large sensitivity of 1327 mA cmà2(mmol Là1[à1in the linear range of 0.01 to 0.1 mmol Là1and 503 mA cmà2(mmol Là1)à1in the linear range of 0.1 to 11 mmol Là1, a response time of shorter than 3 s, good reproducibility and remarkable long-term stability. The superior catalytic efficiency, excellent stability, low cost, and ease of fabrication render CoFe_2O_4 NFs very promising materials in developing an electrochemical device that directly detects hydrazine. 相似文献
13.
以玻碳电极(GCE)为基底电化学聚合制得聚3,4-乙烯二氧噻吩(PEDOT)膜修饰电极,再通过Nafion共固定磷钼酸和石墨烯构建了一种新型的无酶电化学H2O2传感器. 利用扫描电子显微镜(SEM)表征制得的修饰电极,并通过循环伏安法和计时电流法研究了传感器对H2O2的响应性能. 结果表明,在优化条件下,该传感器对H2O2还原具有良好的电催化性能,检测H2O2的线性范围为2.91×10-6 ~ 1.83×10-2 mol•L-1,检出限和灵敏度分别为9.90×10-7 mol•L-1(S/N = 3)和112.5 μA•(mmol•L-1)-1. 此外,该传感器还具有良好的重现性和选择性. 相似文献
14.
利用自组装和电沉积交替的方法制备了基于磷钨酸盐K28Li5H7P8W48O184·92H2O(P8W48)、 碳纳米管和Ni纳米颗粒的复合膜电极, 用于NO2- 的检测. 由于复合膜中P8W48, CNTs和Ni纳米颗粒3种活性成分的协同作用, 所制备的传感器表现出低的检出限、 宽的线性范围和较高的选择性. 将该传感器用于检测果汁中的NO2- , 所得到的回收率在允许的误差范围内. 这种复合膜电极传感器有望在实际应用中高度灵敏地检测NO2- . 相似文献
15.
以四(4-羧苯基)铁卟啉(FeTCPP)作为有机配体,铜离子作为金属节点,利用溶剂热法制备了双金属Cu-FeTCPP金属有机骨架(MOFs)材料,并采用表面活性剂辅助法合成了二维纳米片(Cu-FeTCPP 2DMOFs).该纳米片呈超薄的纳米结构,与三维块体结构(3DMOFs)相比具有更大的比表面积.基于Cu-FeTCPP 2DMOFs的仿酶特性,将其用于催化过氧化氢(H2O2)氧化底物3,3′,5,5′-四甲基联苯胺(TMB)显色,根据显色产物吸光度与H2O2浓度之间的正比关系实现了对H2O2的测定.经稳态动力学分析发现,底物相同时该纳米片的米氏常数Km均比Cu-FeTCPP 3DMOFs的Km小,表明纳米片与底物之间有更好的亲和力,这归因于二维结构大的比表面积和较多易接近的活性位点.基于Cu-FeTCPP 2DMOFs构建的比色检测方法在优化条件下对H2O2的线性检... 相似文献
16.
以石墨烯/纳米金修饰玻碳电极为基底, 用聚乙烯醇与离子液体复合物将辣根过氧化物酶固定于电极表面, 制备了过氧化氢生物传感器. 结果表明, 在0.1 mol/L HAc-NaAc+0.1mol/L KCl(pH=6.5)中, H2O2的氧化峰电流与其浓度在9.55×10-6~6.01×10-3 mol/L间呈良好线性关系, 检出限(3S/N)为3.3×10-7 mol/L. 用标准加入法做回收实验, 回收率在93.4%~100.5%之间. 该传感器对H2O2具有较高的灵敏度和较低的检测限, 稳定性和重现性良好, 使用寿命较长, 且制作成本低, 可多次重复使用. 相似文献
17.
以果皮为原料制备了水溶性碳量子点(CQDs), 透射电子显微镜分析表明其平均粒径为2.4 nm; 红外光谱分析证实CQDs表面富含含氧官能团. 所得CQDs可催化H2O2氧化3,3',5,5'-四甲基联苯胺(TMB)生成蓝色氧化产物(ox-TMB). 基于上述反应, 建立了测定H2O2的分析方法, 在pH=3.5, 温度40 ℃, TMB浓度为1.0 mmol/L及孵育时间15 min的条件下, 当H2O2浓度在5.0~100 μmol/L范围时, ox-TMB的吸光度随H2O2浓度的升高而线 性增强, 方法的检出限为3.0 μmol/L. 鉴于H2O2是肌氨酸氧化酶催化肌氨酸氧化的产物之一, 建立了CQDs催化H2O2氧化TMB间接测定肌氨酸的分析方法. 结果表明, 当肌氨酸浓度在0.5~350 μmol/L范围内时, 吸光度 与其浓度呈良好的线性关系, 方法的检出限为0.3 μmol/L; 将该方法应用于人体尿样的测定, 回收率为94%~99%. 相似文献
18.
In this work,a metal-organic frameworks material MIL-88 was prepared easily using solvent-thermal method,and was first found to have catalytic activities similar to those of biological enzymes such as catalase and peroxidase.The material was characterized by XRD,SEM,TEM,EDX,FT-IR techniques and an N_2 adsorption method.It exhibited peroxidase-like activity through catalytic oxidation of the peroxidase substrate 3,3',5,5'-tetramethylbenzidine(TMB) in the presence of H_2O_2,producing a blue-colored solution.Under optimal conditions,the absorbance at 652 nm is linearly correlated with the concentration of H_2O_2 from 2.0×10~(-6) mol/L to 2.03×10~(-5) mol/L(R~2=0.981) with a detection limit of 5.62×10~(-7) mol/L(S/N=3).More importantly,a sensitive and selective method for ascorbic acid detection was developed using this material as a catalyst.The analytical method for ascorbic acid detection was observed to have a linear range from 2.57×10~(-6) mol/L to 1.01×10~(-5) mol/L(R~2=0.989) with a detection limit of 1.03×10~(-6) mol/L(S/N=3).This work suggests MOFs have advantages of preparing biomimetic catalysts and extends applications of the functional MOFs in the field of biosensor. 相似文献
19.
将DNA功能化多壁碳纳米管(MWCNTs)复合材料修饰于玻碳基底(GC)表面制得DNA-MWCNTs/GC电极,并在此基础上电沉积负载Pt纳米颗粒构建了一种新型无酶H2O2传感电极. 利用扫描电子显微镜(SEM)表征制得的修饰电极,同时通过循环伏安法和计时电流法研究了该传感电极的H2O2响应性能. 结果表明,该传感电极的H2O2检测在0.04 ~ 18.07 mmol·L-1浓度范围内成线性相关,检出限3.85 μmol·L-1(S/N = 3),且有良好的重现性、稳定性与选择性. 相似文献
20.
A novel dual-modal fluorometric and colorimetric method was developed for glucose detection using MnO2 sheets and carbon quantum dots(CQDs). The glucose could be oxidized by glucose oxidase, in accompanied witli the fbnnation of H2O2 intennediate, which resulted in the decomposition of MnO2 sheets, as well as tlie MnO2 sheets(brown) changed to Mn^2+ ions(colorless), which induced the absorption of MnO2 sheet decreased and the fluorescence of CQDs increased, consequently. The linear detection ranges of glucose are 5-1000 μmol/L by fluorescent method and 5-60 μmol/L by colorimetric method. The limits of detection of these two measurements are 2.11 and 2.18 μmol/L, respectively. This method is easy to conduct, has reasonable sensitive and selectivity, and could be applied for the glucose detection in real human senim. 相似文献