Due to the significance of hydrogen peroxide (H(2)O(2)) in biological systems and its practical applications, the development of efficient electrochemical H(2)O(2) sensors holds a special attraction for researchers Various materials such as Prussian blue (PB), heme proteins, carbon nanotubes (CNTs) and transition metals have been applied to the construction of H(2)O(2) sensors In this article, the electrocatalytic H(2)O(2) determinations are mainly focused on because they can provide a superior sensing performance over non-electrocatalytic ones The synergetic effect between nanotechnology and electrochemical H(2)O(2) determination is also highlighted in various aspects In addition, some recent progress for in vivo H(2)O(2) measurements is also presented Finally, the future prospects for more efficient H(2)O(2) sensing are discussed

Recent advances in electrochemical sensing for hydrogen peroxide: a review

On the basis of their unique electrical and mechanical properties, carbon nanotubes (CNTs) have attracted great attention in recent years. A diverse array of methods has been developed to modify CNTs and to assemble them into devices. On the basis of these innovations, many applications that include the use of CNTs have been demonstrated. Transparent electrodes for organic light-emitting diodes (OLEDs), lithium-ion batteries, supercapacitors, and CNT-based electronic components such as field-effect transistors (FETs) have been demonstrated. Furthermore, CNTs have been employed in catalysis and sensing as well as filters and mechanical and biomedical applications. This review highlights illustrative examples from these areas to give an overview of applications of CNTs.

Emerging Applications of Carbon Nanotubes

Sol-gel based materials for biomedical applications

Recent advances in ZnO nanostructures and thin films for biosensor applications: review.

A review of recent advances in nonenzymatic glucose sensors.

A novel hydrazine electrochemical sensor based on a carbon nanotube-wired ZnO nanoflower-modified electrode

A hydroxylamine electrochemical sensor based on electrodeposition of porous ZnO nanofilms onto carbon nanotubes films modified electrode

A good route (template-directed synthetic route) for the fabrication of ZnO hollow nanospheres (ZnO-HNSPs) was proposed. ZnO hollow nanosphere is a wonderful platform to immobilize glucose oxidase for glucose biosensor owing to the high specific surface area and high isoelectric point (IEP). Along with nafion and glucose oxidase (GOD), a glucose sensor was designed. Nafion/ZnO-HNSPs/GOD/GCE displays higher catalytic activity toward the glucose oxidation than Nafion/ZnO nano-Flowers/GOD/GCE. Linear response was obtained over a concentration range from 5.0 × 10 −3  mM to 13.15 mM with a detection limit of 1.0 μM (S/N = 3), and the sensitivity was 65.82 μA/(mM cm 2 ). Satisfyingly, the Nafion/ZnO-HNSPs/GOD/GCE could effectively avoid the interferences from the common interfering species such as uric acid (UA), ascorbic acid (AA), dopamine (DA) and fructose. The Nafion/ZnO-HNSPs/GOD modified electrode allows high sensitivity, excellently selective, stable, and fast amperometric sensing of glucose and thus is promising for the future development of glucose sensors.

A glucose oxidase immobilization platform for glucose biosensor using ZnO hollow nanospheres

Ag2O nanowalls consisting of densely packed nanoplates based on a Cu substrate were synthesized through a facile one-pot hydrothermal method. A new enzymeless glucose sensor of Cu−Ag2O nanowalls was fabricated. The Cu−Ag2O nanowalls showed higher catalysis on glucose oxidation than traditional Ag2O nanoflowers and Cu−Ag2O nanospindles. At an applied potential of 0.4 V, the sensor produced an ultrahigh sensitivity to glucose (GO) of 298.2 μA mM−1. Linear response was obtained over a concentration range from 0.2 mM to 3.2 mM with a detection limit of 0.01 mM (S/N = 3). Satisfyingly, the Cu−Ag2O nanowalls modified electrode was not only successfully employed to eliminate the interferences from uric acid (UA) acid ascorbic (AA) and also fructose (FO) during the catalytic oxidation of glucose. The Cu−Ag2O nanowalls modified electrode allows highly sensitive, excellently selective, stable, and fast amperometric sensing of glucose and thus is promising for the future development of nonenzymatic glucose sensors.

Silver oxide nanowalls grown on Cu substrate as an enzymeless glucose sensor.

A good route (electrodeposition) for the fabrication of gold nanoparticles (nano-Au) attached on ZnO-MWCNTs films modified glassy carbon electrodes (GCE) was proposed. ZnO-MWCNTs films are favored for functioning as the biomimic membrane to immobilize nano-Au. The morphological characterization of nano-Au/ZnO-MWCNTs was examined by scanning electron microscopy (SEM). The performances of the nano-Au/ZnO-MWCNTs/GCE were characterized with cyclic voltammetry (CV), Nyquist plot (EIS) and typical amperometric response ( i – t ). The potential utility of electrodes constructed was demonstrated by applying them to the analytical determination of hydrazine concentration. The catalytic oxidation of hydrazine has a better result on the nano-Au/ZnO-MWCNTs/GCE because of the synergistic effect of nano-Au and ZnO-MWCNTs films. An optimized limit of detection of 0.15 μM was obtained at a signal to noise ratio of 3 and with a fast response time (within 3 s). Additionally, the nano-Au/ZnO-MWCNTs/GCE exhibited a wide linear range from 0.5 to 1800 μM and higher sensitivity. The ease of fabrication and high stability of the modified electrode are the promising features of the proposed sensor.

Cuihong Zhang

Papers

A novel hydrazine electrochemical sensor based on a carbon nanotube-wired ZnO nanoflower-modified electrode

A hydroxylamine electrochemical sensor based on electrodeposition of porous ZnO nanofilms onto carbon nanotubes films modified electrode

A glucose oxidase immobilization platform for glucose biosensor using ZnO hollow nanospheres

Silver oxide nanowalls grown on Cu substrate as an enzymeless glucose sensor.

Enhancement in analytical hydrazine based on gold nanoparticles deposited on ZnO-MWCNTs films