Enzymatic glucose biosensor based on ZnO nanorod array grown by hydrothermal decomposition

Abstract

We report herein a glucose biosensor based on glucose oxidase (GOx) immobilized on ZnO nanorod array grown by hydrothermal decomposition. In a phosphate buffer solution with a pH value of 7.4, negatively charged GOx was immobilized on positively charged ZnO nanorods through electrostatic interaction. At an applied potential of +0.8V versus Ag∕AgCl reference electrode, ZnO nanorods based biosensor presented a high and reproducible sensitivity of 23.1μAcm−2mM−1 with a response time of less than 5s. The biosensor shows a linear range from 0.01to3.45mM and an experiment limit of detection of 0.01mM. An apparent Michaelis-Menten constant of 2.9mM shows a high affinity between glucose and GOx immobilized on ZnO nanorods.

Origin of the surface recombination centers in ZnO nanorods arrays by X-ray photoelectron spectroscopy

“…However, one of the significant differences between nanostructures and an epilayer is the larger surface-to-volume ratio of the former. This large surface-to-volume ratio can be an advantage for some applications, for example sensor devices [1][2][3][4][5]. However, it can also be a problem in other applications, for example, optoelectronic devices such as light emitting diodes [12] and solar-cell [13][14] devices, since surface states are created within the band gap region either because of surface inhomogeneities like nonstoichiometry or because of the selective adsorption of foreign species in addition to the abrupt termination of lattice periodicity.…”

“…Especially, quasi-one-dimensional ZnO nanostructures (e.g. nanorods, nanowires, nanotubes and nanobelts) have been considered highly potential for sensor application such as gas sensor [1][2] and biosensor [3][4][5], and nanophotonic applications such as nanolasers [6][7][8], optical waveguides [9][10][11], and light emitting diodes [12]. However, one of the significant differences between nanostructures and an epilayer is the larger surface-to-volume ratio of the former.…”

Al and Fe co-doped transparent conducting ZnO thin film for mediator-less biosensing application

“…7 Number of biosensors has been reported in the literature for sensing various biomolecules like glucose, cholesterol, DNA, etc. [7][8][9] Though the potential of ZnO as a biosensor matrix has been well established, but its poor electrochemical behaviour is a major hindrance in the development of an efficient integrated biosensor. In this regard, a hybrid composite of ZnO with K 3 [Fe(CN) 6 ] mediator and Fe implanted ZnO has been reported, in which biosensing has been demonstrated in a mediator-free environment.…”

Sol-gel derived nanostructured cerium oxide film for glucose sensor

“…1,2 Glucose biosensor is increasingly being studied because of its importance to monitor blood glucose for treatment of both diabetics and nondiabetics. [2][3][4] Conducting polymers, 5 nanomaterials, 6-10 sol-gels, 2,11-15 etc. have been proposed for the immobilization of glucose oxidase.…”