A new amperometric nanostructured sensor for the analytical determination of hydrogen peroxide

Mediator-free interaction of glucose oxidase, as model enzyme for immobilization, with Al-doped and undoped ZnO thin films laser-deposited on polycarbonate supports

“…GOx/AZO thin film showed fast and sensitive response to glucose as it required a period of 10 s to reach the steady state of current (Figure 6a). This higher sensitivity corresponds to the faster rate of reduction of peroxide on the surface of AZO thin films as compared to the ZnO thin films [41,42]. The limiting current is dependent not only on the concentration of the bulk solution but also on the diffusion thickness, which in turn depends on the rate of breakdown of H2O2 on the surface of thin films.…”

Enhanced electrochemical reduction of hydrogen peroxide on silver paste electrodes modified with surfactant and salt

“…Typical applied potentials used for the amperometric determination of H 2 O 2 reduction in the literature range from -0.7 V (GC/PABS-modified electrodes) [13,14], -0.5 V (Ag nanoparticles in a polyvinyl alcohol film on a Pt electrode) [2], -0.1 V commonly applied in enzymatic biosensors (such as a HRP-modified electrodes) [20,38] and up to 0 V with Prussian Blue [39]. The combination of the sensitive direct detection of H 2 O 2 at low applied potentials without the need for organic catalysts is a distinct advantage in many potential applications.…”

“…This has made it highly relevant in the food, environmental, clinical and pharmaceutical industries and related areas of research [1,2]. The importance of hydrogen peroxide is related to its unique oxidising properties.…”

“…However, these techniques have proved to be time-consuming, difficult for automated detection and highly prone to interferences [12]. Recently, electrochemical methods have become the techniques of choice due to their low cost and high sensitivity, resulting in an effective way to examine the reactions of many substances [2,[13][14][15][16]. In attempting to mimic biological systems, hydrogen peroxide has been determined by electrodes modified with redox proteins and enzymes such as haemoglobin, soybean peroxidase, myoglobin [12,17,18] and horseradish peroxidase (HRP) [12,19,20].…”

“…Recently, interest has been shown in using nanoparticles (especially nanoparticles of noble metals such as gold) [29][30][31] for the electro-analytical detection of hydrogen peroxide [2,13,32,33]. The microelectrode arrays created by the deposition of metallic nanoparticles on electrodes have been shown to significantly improve the sensitivity of electro-analytical sensing methods due to their large specific surface areas, excellent conductivities and biocompatibilities.…”