ZnO nanostructures in enzyme biosensors

Abstract

Biosensing has developed tremendously since it was demonstrated by Leland C. Clark Jr. in 1962. ZnO nanomaterials are attractive candidates for fabricating biosensors, because of their diverse range of nanostructures, high electron mobility, chemical stability, electrochemical activity, high isoelectric points which promote enzyme adsorption, biocompatibility, and piezoelectric properties. This review covers ZnO nanostructures applied in enzyme biosensors, in the light of electrochemical transduction and field effect transduction. Different assembly processes and immobilization methods have been used to load enzymes into various ZnO nanostructures, providing enzymes with favorable micro-environments and enhancing their sensing performance. We briefly describe recent trends in ZnO syntheses, and the analytical performance of the fabricated biosensors, summarize the advantages of using ZnO nanostructures in biosensors, and conclude with future challenges and prospects.

Rectangular flake-like mesoporous NiCo2O4 as enzyme mimic for glucose biosensing and biofuel cell

“…On the other hand, fuel cells, especially glucose biofuel cells (GBFCs), with the help of catalyst, can produce electric energy in an efficient and steady way and are considered as the promising next-generation energy devices due to their available and easy capability to harvest electrical energy from glucose fuel [1]. Generally, glucose biosensors and GBFCs can be classified into two categories according to the types of catalysts, namely enzymebased and nonenzyme-based ones [2][3][4]. Research findings demonstrate that enzymatic catalysts exhibit high activity and excellent selectivity, but the unstable operating environment and fragile stability greatly hinder their practical applications [5,6].…”

Ultra-low charge transfer resistance carbons by one-pot hydrothermal method for glucose sensing

“…When the bare GCE is covered with nafion, the slope of GCE/ nafion (Fig. 5a, pink dot line) is higher than that of GCE, confirming that the diffusion resistance of GCE/nafion is larger than that of bare GCE [51]. However, when NS-C is assembled on the surface of GCE, the R ct of the GCE/ …”

Investigation of the Influence of the As-Grown ZnO Nanorods and Applied Potentials on an Electrochemical Sensor for In-Vitro Glucose Monitoring

“…In addition, ZnO NRs provide a free path of electrons between the glucose and the surface of the electrode, and a high surface-to-bulk ratio. Glucose oxidase can be adsorbed in a large surface area that is provided by the high surface-to-volume ratio of the as-grown ZnO NRs [20]. …”

“…In addition, ZnO NRs provide a free path of electrons between the glucose and the surface of the electrode, and a high surface-to-bulk ratio. Glucose oxidase can be adsorbed in a large surface area that is provided by the high surface-to-volume ratio of the as-grown ZnO NRs [20]. For device characterization, all measurements were performed using a Source Meter Keithley 2410 and an electrochemical impedance analyzer (Gamry potentiostat, Gamry Instruments, Warminster, PA, USA), and the measurements were performed in a PBS with a pH of 7.4.…”